Номер 137, страница 84, часть 2 - гдз по физике 9 класс учебник Генденштейн, Булатова

Авторы: Генденштейн Л. Э., Булатова А. А., Корнильев И. Н., Кошкина А. В.

Тип: Учебник

Издательство: Бином

Год издания: 2016 - 2026

Часть: 2

Цвет обложки: бирюзовый

ISBN: 978-5-9963-3062-1

Часть 2. Материалы для повторения при подготовке к экзамену. 5. Тепловые явления - номер 137, страница 84.

App\Models\Task {#1030 // resources/views/models/task/default.blade.php
  #connection: "mysql"
  #table: "tasks"
  #primaryKey: "id"
  #keyType: "int"
  +incrementing: true
  #with: []
  #withCount: []
  +preventsLazyLoading: false
  #perPage: 15
  +exists: true
  +wasRecentlyCreated: false
  #escapeWhenCastingToString: false
  #attributes: array:24 [
    "id" => 1434219
    "created_at" => "2026-04-10 13:58:26"
    "updated_at" => null
    "field_page_start" => "84"
    "field_page_end" => null
    "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik/ekzam-137"
    "field_display_title" => "137"
    "field_outside_task" => null
    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1037
      #items: array:1 [
        0 => App\Models\Term {#1036
          #connection: "mysql"
          #table: "terms"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: false
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
          #original: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
          #changes: []
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          #dateFormat: null
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          +timestamps: true
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          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "field_metatags_title" => null
    "field_metatags_description" => null
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    "field_description_bottom" => null
    "field_match" => null
    "breadcrumbs" => []
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      #items: []
      #escapeWhenCastingToString: false
    }
    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1075
      #items: array:1 [
        0 => App\Models\Branch {#1034
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1433262
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => null
            "field_branch_order" => "2"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1039
              #items: array:1 [
                0 => App\Models\Term {#1038
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
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                  #escapeWhenCastingToString: false
                  #attributes: array:7 [
                    "id" => 31
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Часть"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Часть"
                      "field_creative_case" => "Частью"
                      "field_dative_case" => "Части"
                      "field_genitive_case" => "Части"
                      "field_nominative_case" => "Часть"
                      "field_prepositional_case" => "Части"
                    ]
                    "field_page_check_not_needed" => "1"
                    "field_short_name" => "ч."
                  ]
                  #original: array:7 [
                    "id" => 31
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Часть"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Часть"
                      "field_creative_case" => "Частью"
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                      "field_genitive_case" => "Части"
                      "field_nominative_case" => "Часть"
                      "field_prepositional_case" => "Части"
                    ]
                    "field_page_check_not_needed" => "1"
                    "field_short_name" => "ч."
                  ]
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
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            "field_navigation_title" => null
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            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
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              #items: array:1 [
                0 => App\Models\Book {#1041
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
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                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:50 [
                    "id" => 2980
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1042
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1044
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1046
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1048
                      #items: array:4 [ …4]
                      #escapeWhenCastingToString: false
                    }
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1053
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1054
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1056
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1058
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1060
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1061
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1062
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1063
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1064
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1065
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
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                    "field_publication_year_until" => null
                    "field_part" => "1, 2"
                    "field_part_writing" => "Часть"
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1111"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/gendenshtejn-u/"
                    "field_isbn" => "978-5-9963-3062-1"
                    "field_cover" => array:2 [
                      0 => "/media/fizika_09/gendenshtejn-u/covers/cover1.webp?ts=1759256052"
                      1 => "/media/fizika_09/gendenshtejn-u/covers/cover2.webp?ts=1759256052"
                    ]
                    "field_cover_alts" => array:2 [
                      0 => ""
                      1 => ""
                    ]
                    "field_covers" => array:2 [
                      0 => array:4 [ …4]
                      1 => array:4 [ …4]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1067
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1068
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1069
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1070
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
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                      "subject" => 556
                      "class_subject" => 493
                    ]
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                  #original: array:50 [
                    "id" => 2980
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
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                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1042}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1044}
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                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1053}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1054}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1056}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1058}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1060}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1061}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1062}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1063}
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                      1 => array:4 [ …4]
                    ]
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                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1067}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1068}
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                    "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1070}
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                    ]
                  ]
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            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1072
              #items: []
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    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1151
      #items: array:3 [
        0 => App\Models\Branch {#1161
          #connection: "mysql"
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                  #connection: "mysql"
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                      #items: array:1 [
                        0 => App\Models\Term {#1163
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
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                          #attributes: array:10 [
                            "id" => 6493
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Физика"
                            "field_abbreviated_name" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "физику"
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                              "field_genitive_case" => "физики"
                              "field_nominative_case" => "физика"
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                            ]
                            "field_foreign_lang_name" => null
                            "field_short_name" => null
                            "field_subject_type" => "technical_subject"
                            "field_translit" => "fizika"
                          ]
                          #original: array:10 [
                            "id" => 6493
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Физика"
                            "field_abbreviated_name" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "физику"
                              "field_creative_case" => "физикой"
                              "field_dative_case" => "физике"
                              "field_genitive_case" => "физики"
                              "field_nominative_case" => "физика"
                              "field_prepositional_case" => "физике"
                            ]
                            "field_foreign_lang_name" => null
                            "field_short_name" => null
                            "field_subject_type" => "technical_subject"
                            "field_translit" => "fizika"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1167
                      #items: array:1 [
                        0 => App\Models\Term {#1168
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 5458
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "9"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "девятый"
                              "field_creative_case" => "девятым"
                              "field_dative_case" => "девятому"
                              "field_genitive_case" => "девятого"
                              "field_nominative_case" => "девятый"
                              "field_prepositional_case" => "девятом"
                            ]
                            "field_translit" => "devjatyj"
                          ]
                          #original: array:6 [
                            "id" => 5458
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "9"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "девятый"
                              "field_creative_case" => "девятым"
                              "field_dative_case" => "девятому"
                              "field_genitive_case" => "девятого"
                              "field_nominative_case" => "девятый"
                              "field_prepositional_case" => "девятом"
                            ]
                            "field_translit" => "devjatyj"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1169
                      #items: array:1 [
                        0 => App\Models\Term {#1170
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 5208
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Бином"
                            "field_cases" => null
                            "field_translit" => "binom"
                          ]
                          #original: array:6 [
                            "id" => 5208
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Бином"
                            "field_cases" => null
                            "field_translit" => "binom"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1171
                      #items: array:4 [
                        0 => App\Models\Term {#1172
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 4104
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Генденштейн"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Лев"
                            "field_patronymic" => "Элевич"
                            "field_surname_rp" => "Генденштейна"
                          ]
                          #original: array:12 [
                            "id" => 4104
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Генденштейн"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Лев"
                            "field_patronymic" => "Элевич"
                            "field_surname_rp" => "Генденштейна"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        1 => App\Models\Term {#1173
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 3936
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Булатова"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Альбина"
                            "field_patronymic" => "Александрова"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 3936
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Булатова"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Альбина"
                            "field_patronymic" => "Александрова"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        2 => App\Models\Term {#1174
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 4679
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Корнильев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Игорь"
                            "field_patronymic" => "Николаевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4679
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Корнильев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Игорь"
                            "field_patronymic" => "Николаевич"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        3 => App\Models\Term {#1175
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 4758
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Кошкина"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Анжелика"
                            "field_patronymic" => "Васильевна"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4758
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Кошкина"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Анжелика"
                            "field_patronymic" => "Васильевна"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1176
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1177
                      #items: array:1 [
                        0 => App\Models\Term {#1178
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [
                            "id" => 6671
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "учебник"
                              "field_creative_case" => "учебником"
                              "field_dative_case" => "учебнику"
                              "field_genitive_case" => "учебника"
                              "field_nominative_case" => "учебник"
                              "field_prepositional_case" => "учебнике"
                            ]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik"
                          ]
                          #original: array:10 [
                            "id" => 6671
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "учебник"
                              "field_creative_case" => "учебником"
                              "field_dative_case" => "учебнику"
                              "field_genitive_case" => "учебника"
                              "field_nominative_case" => "учебник"
                              "field_prepositional_case" => "учебнике"
                            ]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1179
                      #items: array:1 [
                        0 => App\Models\Term {#1180
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "rossiya"
                          ]
                          #original: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "rossiya"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1181
                      #items: array:1 [
                        0 => App\Models\Term {#1182
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "moskva"
                          ]
                          #original: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "moskva"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1183
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1184
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1185
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1186
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1187
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1188
                      #items: array:1 [
                        0 => App\Models\Term {#1189
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 5395
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Орлов"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Владимир"
                            "field_patronymic" => "Алексеевич"
                            "field_surname_rp" => "Орлова"
                          ]
                          #original: array:12 [
                            "id" => 5395
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Орлов"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Владимир"
                            "field_patronymic" => "Алексеевич"
                            "field_surname_rp" => "Орлова"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2016"
                    "field_publication_year_until" => null
                    "field_part" => "1, 2"
                    "field_part_writing" => "Часть"
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1111"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/gendenshtejn-u/"
                    "field_isbn" => "978-5-9963-3062-1"
                    "field_cover" => array:2 [
                      0 => "/media/fizika_09/gendenshtejn-u/covers/cover1.webp?ts=1759256052"
                      1 => "/media/fizika_09/gendenshtejn-u/covers/cover2.webp?ts=1759256052"
                    ]
                    "field_cover_alts" => array:2 [
                      0 => ""
                      1 => ""
                    ]
                    "field_covers" => array:2 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/gendenshtejn-u/covers/cover1.webp?ts=1759256052"
                        "alt" => ""
                        "width" => "1863"
                        "height" => "2813"
                      ]
                      1 => array:4 [
                        "path" => "/media/fizika_09/gendenshtejn-u/covers/cover2.webp?ts=1759256052"
                        "alt" => ""
                        "width" => "1863"
                        "height" => "2809"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1190
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1191
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1192
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1193
                      #items: array:1 [
                        0 => App\Models\Term {#1194
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 6978
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "бирюзовый"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "бирюзовый"
                              "field_creative_case" => "бирюзовым"
                              "field_dative_case" => "бирюзовому"
                              "field_genitive_case" => "бирюзового"
                              "field_nominative_case" => "бирюзовый"
                              "field_prepositional_case" => "бирюзовом"
                            ]
                            "field_translit" => "biruzovyy"
                          ]
                          #original: array:6 [
                            "id" => 6978
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "бирюзовый"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "бирюзовый"
                              "field_creative_case" => "бирюзовым"
                              "field_dative_case" => "бирюзовому"
                              "field_genitive_case" => "бирюзового"
                              "field_nominative_case" => "бирюзовый"
                              "field_prepositional_case" => "бирюзовом"
                            ]
                            "field_translit" => "biruzovyy"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
                  #original: array:50 [
                    "id" => 2980
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1166}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1167}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1169}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1171}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1176}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1177}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1179}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1181}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1183}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1184}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1185}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1186}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1187}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1188}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2016"
                    "field_publication_year_until" => null
                    "field_part" => "1, 2"
                    "field_part_writing" => "Часть"
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1111"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/gendenshtejn-u/"
                    "field_isbn" => "978-5-9963-3062-1"
                    "field_cover" => array:2 [
                      0 => "/media/fizika_09/gendenshtejn-u/covers/cover1.webp?ts=1759256052"
                      1 => "/media/fizika_09/gendenshtejn-u/covers/cover2.webp?ts=1759256052"
                    ]
                    "field_cover_alts" => array:2 [
                      0 => ""
                      1 => ""
                    ]
                    "field_covers" => array:2 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/gendenshtejn-u/covers/cover1.webp?ts=1759256052"
                        "alt" => ""
                        "width" => "1863"
                        "height" => "2813"
                      ]
                      1 => array:4 [
                        "path" => "/media/fizika_09/gendenshtejn-u/covers/cover2.webp?ts=1759256052"
                        "alt" => ""
                        "width" => "1863"
                        "height" => "2809"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1190}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1191}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1192}
                    "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1193}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1195
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1433262
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => null
            "field_branch_order" => "2"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1165}
            "field_page_start" => "4"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1197}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1195}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Branch {#1196
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1434390
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Материалы для повторения при подготовке к экзамену"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1198
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "56"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1199
              #items: array:1 [
                0 => App\Models\Book {#1164}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1200
              #items: array:1 [
                0 => App\Models\Branch {#1034}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1434390
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Материалы для повторения при подготовке к экзамену"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1198}
            "field_page_start" => "56"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1199}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1200}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1201
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1434395
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "5. Тепловые явления"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1202
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "78"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1203
              #items: array:1 [
                0 => App\Models\Book {#1164}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1246
              #items: array:1 [
                0 => App\Models\Branch {#1204
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [
                    "id" => 1434390
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Материалы для повторения при подготовке к экзамену"
                    "field_branch_order" => null
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1206
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_page_start" => "56"
                    "field_branch_display" => "0"
                    "field_branch_expanded" => "0"
                    "field_display_branch_in_title" => "1"
                    "field_display_task_interval" => "0"
                    "field_display_branch_page" => "1"
                    "field_branch_title_in_content" => "0"
                    "field_navigation_title" => null
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1205
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1238
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                  ]
                  #original: array:24 [
                    "id" => 1434390
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Материалы для повторения при подготовке к экзамену"
                    "field_branch_order" => null
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1206}
                    "field_page_start" => "56"
                    "field_branch_display" => "0"
                    "field_branch_expanded" => "0"
                    "field_display_branch_in_title" => "1"
                    "field_display_task_interval" => "0"
                    "field_display_branch_page" => "1"
                    "field_branch_title_in_content" => "0"
                    "field_navigation_title" => null
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1205}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1238}
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1434395
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "5. Тепловые явления"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1202}
            "field_page_start" => "78"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1203}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1246}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1110
      #items: array:2 [
        0 => App\Models\Element {#1140
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:7 [
            "id" => 1696912
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1130
              #items: array:1 [
                0 => App\Models\Edition {#1139
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 6168
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1138
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1136
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1135
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1134
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6168
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1138}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
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                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1136}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1135}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1134}
                    "field_content_source" => null
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                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1434219"
              "type" => "task"
            ]
            "text" => "<p><strong>137.</strong> С какой высоты должна падать вода, чтобы при ударе о землю она закипала, если бы можно было пренебречь сопротивлением воздуха? Примите, что начальная температура воды равна $20 \text{ °C}$ и половина механической энергии воды переходит в её внутреннюю энергию.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "137-1.jpg"
                "alt" => null
                "width" => "1581"
                "height" => 363
                "path" => "/media/fizika_09/gendenshtejn-u/0-ekzam/137-1.webp?ts=1759348438"
              ]
            ]
          ]
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            "id" => 1696912
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1130}
            "task" => array:2 [
              "refs" => "1434219"
              "type" => "task"
            ]
            "text" => "<p><strong>137.</strong> С какой высоты должна падать вода, чтобы при ударе о землю она закипала, если бы можно было пренебречь сопротивлением воздуха? Примите, что начальная температура воды равна $20 \text{ °C}$ и половина механической энергии воды переходит в её внутреннюю энергию.</p>"
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          #attributes: array:6 [
            "id" => 1780982
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
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                0 => App\Models\Edition {#1132
                  #connection: "mysql"
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                  #attributes: array:21 [
                    "id" => 6515
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1128
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                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
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                    "id" => 6515
                    "created_at" => "2026-04-10 13:58:26"
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                    "title" => "Решение"
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            "task" => array:2 [
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              "type" => "task"
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            "text" => "<p><strong>Дано:</strong></p><p>Начальная температура воды: $t_1 = 20 \text{ °C}$</p><p>Конечная температура воды (температура кипения): $t_2 = 100 \text{ °C}$</p><p>Доля механической энергии, переходящая во внутреннюю: $\eta = 0.5$</p><p>Удельная теплоемкость воды: $c = 4200 \frac{\text{Дж}}{\text{кг} \cdot \text{°C}}$</p><p>Ускорение свободного падения: $g \approx 9.8 \frac{\text{м}}{\text{с}^2}$</p><p>Система СИ:</p><p>Так как в расчетах используется разность температур, которая одинакова в шкалах Цельсия и Кельвина ($\Delta t = 100 \text{ °C} - 20 \text{ °C} = 80 \text{ °C} = 80 \text{ К}$), перевод температур в Кельвины не обязателен. Остальные величины представлены в единицах СИ.</p><p><strong>Найти:</strong></p><p>Высота падения $\text{h}$.</p><p><strong>Решение:</strong></p><p>При падении воды с высоты $\text{h}$ её потенциальная энергия $E_p$ переходит в кинетическую. Поскольку сопротивлением воздуха пренебрегаем, полная механическая энергия воды в момент перед ударом о землю равна её начальной потенциальной энергии:</p><p>$E_{мех} = E_p = mgh$</p><p>где $\text{m}$ – масса воды.</p><p>Согласно условию задачи, половина $(\eta = 0.5)$ этой энергии при ударе превращается во внутреннюю энергию воды, что приводит к её нагреву. Изменение внутренней энергии $\Delta U$ составляет:</p><p>$\Delta U = \eta \cdot E_{мех} = 0.5 \cdot mgh$</p><p>Для того чтобы вода начала кипеть, её необходимо нагреть от начальной температуры $t_1$ до температуры кипения $t_2$. Количество теплоты $\text{Q}$, необходимое для этого, определяется формулой:</p><p>$Q = c \cdot m \cdot (t_2 - t_1)$</p><p>где $\text{c}$ – удельная теплоемкость воды.</p><p>Приравняем количество теплоты, полученное водой, к той части механической энергии, которая перешла во внутреннюю энергию:</p><p>$\Delta U = Q$</p><p>$0.5 \cdot mgh = c \cdot m \cdot (t_2 - t_1)$</p><p>Масса воды $\text{m}$ в обеих частях уравнения сокращается:</p><p>$0.5 \cdot gh = c \cdot (t_2 - t_1)$</p><p>Из этого соотношения выразим искомую высоту $\text{h}$:</p><p>$h = \frac{c \cdot (t_2 - t_1)}{0.5 \cdot g} = \frac{2c(t_2 - t_1)}{g}$</p><p>Подставим числовые значения в формулу:</p><p>$h = \frac{2 \cdot 4200 \frac{\text{Дж}}{\text{кг} \cdot \text{°C}} \cdot (100 \text{ °C} - 20 \text{ °C})}{9.8 \frac{\text{м}}{\text{с}^2}} = \frac{2 \cdot 4200 \cdot 80}{9.8} \text{ м}$</p><p>$h = \frac{672000}{9.8} \text{ м} \approx 68571.4 \text{ м}$</p><p>Для наглядности переведем результат в километры:</p><p>$h \approx 68.6 \text{ км}$</p><p><strong>Ответ:</strong></p><p>Вода должна падать с высоты примерно 68.6 км, чтобы при ударе о землю она закипала.</p>"
          ]
          #original: array:6 [
            "id" => 1780982
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1124}
            "task" => array:2 [
              "refs" => "1434219"
              "type" => "task"
            ]
            "text" => "<p><strong>Дано:</strong></p><p>Начальная температура воды: $t_1 = 20 \text{ °C}$</p><p>Конечная температура воды (температура кипения): $t_2 = 100 \text{ °C}$</p><p>Доля механической энергии, переходящая во внутреннюю: $\eta = 0.5$</p><p>Удельная теплоемкость воды: $c = 4200 \frac{\text{Дж}}{\text{кг} \cdot \text{°C}}$</p><p>Ускорение свободного падения: $g \approx 9.8 \frac{\text{м}}{\text{с}^2}$</p><p>Система СИ:</p><p>Так как в расчетах используется разность температур, которая одинакова в шкалах Цельсия и Кельвина ($\Delta t = 100 \text{ °C} - 20 \text{ °C} = 80 \text{ °C} = 80 \text{ К}$), перевод температур в Кельвины не обязателен. Остальные величины представлены в единицах СИ.</p><p><strong>Найти:</strong></p><p>Высота падения $\text{h}$.</p><p><strong>Решение:</strong></p><p>При падении воды с высоты $\text{h}$ её потенциальная энергия $E_p$ переходит в кинетическую. Поскольку сопротивлением воздуха пренебрегаем, полная механическая энергия воды в момент перед ударом о землю равна её начальной потенциальной энергии:</p><p>$E_{мех} = E_p = mgh$</p><p>где $\text{m}$ – масса воды.</p><p>Согласно условию задачи, половина $(\eta = 0.5)$ этой энергии при ударе превращается во внутреннюю энергию воды, что приводит к её нагреву. Изменение внутренней энергии $\Delta U$ составляет:</p><p>$\Delta U = \eta \cdot E_{мех} = 0.5 \cdot mgh$</p><p>Для того чтобы вода начала кипеть, её необходимо нагреть от начальной температуры $t_1$ до температуры кипения $t_2$. Количество теплоты $\text{Q}$, необходимое для этого, определяется формулой:</p><p>$Q = c \cdot m \cdot (t_2 - t_1)$</p><p>где $\text{c}$ – удельная теплоемкость воды.</p><p>Приравняем количество теплоты, полученное водой, к той части механической энергии, которая перешла во внутреннюю энергию:</p><p>$\Delta U = Q$</p><p>$0.5 \cdot mgh = c \cdot m \cdot (t_2 - t_1)$</p><p>Масса воды $\text{m}$ в обеих частях уравнения сокращается:</p><p>$0.5 \cdot gh = c \cdot (t_2 - t_1)$</p><p>Из этого соотношения выразим искомую высоту $\text{h}$:</p><p>$h = \frac{c \cdot (t_2 - t_1)}{0.5 \cdot g} = \frac{2c(t_2 - t_1)}{g}$</p><p>Подставим числовые значения в формулу:</p><p>$h = \frac{2 \cdot 4200 \frac{\text{Дж}}{\text{кг} \cdot \text{°C}} \cdot (100 \text{ °C} - 20 \text{ °C})}{9.8 \frac{\text{м}}{\text{с}^2}} = \frac{2 \cdot 4200 \cdot 80}{9.8} \text{ м}$</p><p>$h = \frac{672000}{9.8} \text{ м} \approx 68571.4 \text{ м}$</p><p>Для наглядности переведем результат в километры:</p><p>$h \approx 68.6 \text{ км}$</p><p><strong>Ответ:</strong></p><p>Вода должна падать с высоты примерно 68.6 км, чтобы при ударе о землю она закипала.</p>"
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            "created_at" => "2026-04-10 13:58:26"
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            "tasks" => Illuminate\Database\Eloquent\Collection {#1339
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                    "next" => array:2 [ …2]
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№137 (с. 84)
Условие. №137 (с. 84)
скриншот условия
Физика, 9 класс Учебник, авторы: Генденштейн Лев Элевич, Булатова Альбина Александрова, Корнильев Игорь Николаевич, Кошкина Анжелика Васильевна, издательство Бином, Москва, 2016, бирюзового цвета, Часть 2, страница 84, номер 137, Условие

137. С какой высоты должна падать вода, чтобы при ударе о землю она закипала, если бы можно было пренебречь сопротивлением воздуха? Примите, что начальная температура воды равна $20 \text{ °C}$ и половина механической энергии воды переходит в её внутреннюю энергию.

Решение. №137 (с. 84)

Дано:

Начальная температура воды: $t_1 = 20 \text{ °C}$

Конечная температура воды (температура кипения): $t_2 = 100 \text{ °C}$

Доля механической энергии, переходящая во внутреннюю: $\eta = 0.5$

Удельная теплоемкость воды: $c = 4200 \frac{\text{Дж}}{\text{кг} \cdot \text{°C}}$

Ускорение свободного падения: $g \approx 9.8 \frac{\text{м}}{\text{с}^2}$

Система СИ:

Так как в расчетах используется разность температур, которая одинакова в шкалах Цельсия и Кельвина ($\Delta t = 100 \text{ °C} - 20 \text{ °C} = 80 \text{ °C} = 80 \text{ К}$), перевод температур в Кельвины не обязателен. Остальные величины представлены в единицах СИ.

Найти:

Высота падения $\text{h}$.

Решение:

При падении воды с высоты $\text{h}$ её потенциальная энергия $E_p$ переходит в кинетическую. Поскольку сопротивлением воздуха пренебрегаем, полная механическая энергия воды в момент перед ударом о землю равна её начальной потенциальной энергии:

$E_{мех} = E_p = mgh$

где $\text{m}$ – масса воды.

Согласно условию задачи, половина $(\eta = 0.5)$ этой энергии при ударе превращается во внутреннюю энергию воды, что приводит к её нагреву. Изменение внутренней энергии $\Delta U$ составляет:

$\Delta U = \eta \cdot E_{мех} = 0.5 \cdot mgh$

Для того чтобы вода начала кипеть, её необходимо нагреть от начальной температуры $t_1$ до температуры кипения $t_2$. Количество теплоты $\text{Q}$, необходимое для этого, определяется формулой:

$Q = c \cdot m \cdot (t_2 - t_1)$

где $\text{c}$ – удельная теплоемкость воды.

Приравняем количество теплоты, полученное водой, к той части механической энергии, которая перешла во внутреннюю энергию:

$\Delta U = Q$

$0.5 \cdot mgh = c \cdot m \cdot (t_2 - t_1)$

Масса воды $\text{m}$ в обеих частях уравнения сокращается:

$0.5 \cdot gh = c \cdot (t_2 - t_1)$

Из этого соотношения выразим искомую высоту $\text{h}$:

$h = \frac{c \cdot (t_2 - t_1)}{0.5 \cdot g} = \frac{2c(t_2 - t_1)}{g}$

Подставим числовые значения в формулу:

$h = \frac{2 \cdot 4200 \frac{\text{Дж}}{\text{кг} \cdot \text{°C}} \cdot (100 \text{ °C} - 20 \text{ °C})}{9.8 \frac{\text{м}}{\text{с}^2}} = \frac{2 \cdot 4200 \cdot 80}{9.8} \text{ м}$

$h = \frac{672000}{9.8} \text{ м} \approx 68571.4 \text{ м}$

Для наглядности переведем результат в километры:

$h \approx 68.6 \text{ км}$

Ответ:

Вода должна падать с высоты примерно 68.6 км, чтобы при ударе о землю она закипала.

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