Номер 1.5, страница 137 - гдз по физике 8-11 класс учебник, задачник Гельфгат, Генденштейн

Физика, 8-11 класс Учебник, задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2005

Авторы: Гельфгат И. М., Генденштейн Л. Э., Кирик Л. А.

Тип: Учебник, задачник

Издательство: Илекса

Год издания: 2005 - 2026

Цвет обложки: синий мужчина в красном, летит на черном шаре

ISBN: 978-5-89237-332-6

Тесты. Первый уровень - номер 1.5, страница 137.

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" => 1288858
    "created_at" => "2026-04-10 13:58:26"
    "updated_at" => null
    "field_page_start" => "137"
    "field_page_end" => null
    "field_url" => "/8-klass/fizika/ileksa-gelfgat-uchebnik/test1-5"
    "field_display_title" => "1.5"
    "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: []
          #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
    "field_match" => null
    "breadcrumbs" => []
    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1035
      #items: []
      #escapeWhenCastingToString: false
    }
    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1046
      #items: array:1 [
        0 => App\Models\Branch {#1045
          #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" => 1287894
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Тесты"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1047
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "136"
            "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 {#1083
              #items: array:1 [
                0 => App\Models\Book {#1048
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:50 [
                    "id" => 5401
                    "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 {#1050
                      #items: array:1 [
                        0 => App\Models\Term {#1049
                          #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" => 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"
                          ]
                          #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 {#1051
                      #items: array:4 [
                        0 => App\Models\Term {#1052
                          #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" => 5457
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "8"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "восьмой"
                              "field_creative_case" => "восьмым"
                              "field_dative_case" => "восьмому"
                              "field_genitive_case" => "восьмого"
                              "field_nominative_case" => "восьмой"
                              "field_prepositional_case" => "восьмом"
                            ]
                            "field_translit" => "vosmoj"
                          ]
                          #original: array:6 [
                            "id" => 5457
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "8"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "восьмой"
                              "field_creative_case" => "восьмым"
                              "field_dative_case" => "восьмому"
                              "field_genitive_case" => "восьмого"
                              "field_nominative_case" => "восьмой"
                              "field_prepositional_case" => "восьмом"
                            ]
                            "field_translit" => "vosmoj"
                          ]
                          #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 {#1053
                          #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 => "*"
                          ]
                        }
                        2 => App\Models\Term {#1054
                          #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" => 5459
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "10"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "десятый"
                              "field_creative_case" => "десятым"
                              "field_dative_case" => "десятому"
                              "field_genitive_case" => "десятого"
                              "field_nominative_case" => "десятый"
                              "field_prepositional_case" => "десятом"
                            ]
                            "field_translit" => "desjatyj"
                          ]
                          #original: array:6 [
                            "id" => 5459
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "10"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "десятый"
                              "field_creative_case" => "десятым"
                              "field_dative_case" => "десятому"
                              "field_genitive_case" => "десятого"
                              "field_nominative_case" => "десятый"
                              "field_prepositional_case" => "десятом"
                            ]
                            "field_translit" => "desjatyj"
                          ]
                          #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 {#1055
                          #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" => 5460
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "11"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "одиннадцатый"
                              "field_creative_case" => "одиннадцатым"
                              "field_dative_case" => "одиннадцатому"
                              "field_genitive_case" => "одинадцатого"
                              "field_nominative_case" => "одинадцатый"
                              "field_prepositional_case" => "одиннадцатом"
                            ]
                            "field_translit" => "odinadcatyj"
                          ]
                          #original: array:6 [
                            "id" => 5460
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "11"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "odinadcatyj"
                          ]
                          #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 {#1056
                      #items: array:1 [
                        0 => App\Models\Term {#1057
                          #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" => 5158
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Илекса"
                            "field_cases" => null
                            "field_translit" => "ileksa"
                          ]
                          #original: array:6 [
                            "id" => 5158
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Илекса"
                            "field_cases" => null
                            "field_translit" => "ileksa"
                          ]
                          #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 {#1058
                      #items: array:3 [
                        0 => App\Models\Term {#1059
                          #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" => 4102
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Гельфгат"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Илья"
                            "field_patronymic" => "Маркович"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4102
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Гельфгат"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Илья"
                            "field_patronymic" => "Маркович"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
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                          +timestamps: true
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                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        1 => App\Models\Term {#1060
                          #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 => "*"
                          ]
                        }
                        2 => App\Models\Term {#1061
                          #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" => 4583
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Кирик"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Леонид"
                            "field_patronymic" => "Анатольевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4583
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Кирик"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Леонид"
                            "field_patronymic" => "Анатольевич"
                            "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 {#1062
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1063
                      #items: array:1 [
                        0 => App\Models\Term {#1064
                          #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" => 6673
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник, задачник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik, zadachnik"
                          ]
                          #original: array:10 [
                            "id" => 6673
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник, задачник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik, zadachnik"
                          ]
                          #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 {#1065
                      #items: array:1 [
                        0 => App\Models\Term {#1066
                          #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 [ …6]
                            "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 [ …6]
                            "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 {#1067
                      #items: array:1 [
                        0 => App\Models\Term {#1068
                          #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 [ …6]
                            "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 [ …6]
                            "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 {#1069
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1070
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1071
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1072
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => "6"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1073
                      #items: array:1 [
                        0 => App\Models\Term {#1074
                          #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" => 35
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "исправленное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "ispravlennoe"
                          ]
                          #original: array:6 [
                            "id" => 35
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "исправленное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "ispravlennoe"
                          ]
                          #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" => Illuminate\Database\Eloquent\Collection {#1075
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "мужчина в красном, летит на черном шаре"
                    "field_publication_year" => "2005"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "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" => "1001"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_08/gelfgat-u/"
                    "field_isbn" => "978-5-89237-332-6"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                        "alt" => ""
                        "width" => "1813"
                        "height" => "2441"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1076
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1077
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1078
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/8-klass/fizika/ileksa-gelfgat-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1079
                      #items: array:1 [
                        0 => App\Models\Term {#1080
                          #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" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "siniy"
                          ]
                          #original: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "siniy"
                          ]
                          #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" => 379
                      "subject" => 556
                      "class_subject" => 492
                    ]
                  ]
                  #original: array:50 [
                    "id" => 5401
                    "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 {#1050}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1051}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1056}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1058}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1062}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1063}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1065}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1067}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1069}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1070}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1071}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1072}
                    "field_publication_number" => "6"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1073}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1075}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "мужчина в красном, летит на черном шаре"
                    "field_publication_year" => "2005"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "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" => "1001"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_08/gelfgat-u/"
                    "field_isbn" => "978-5-89237-332-6"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                        "alt" => ""
                        "width" => "1813"
                        "height" => "2441"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1076}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1077}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1078}
                    "field_url" => "/8-klass/fizika/ileksa-gelfgat-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1079}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 379
                      "subject" => 556
                      "class_subject" => 492
                    ]
                  ]
                  #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 {#1081
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1287894
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Тесты"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1047}
            "field_page_start" => "136"
            "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 {#1083}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1081}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1115
      #items: array:2 [
        0 => App\Models\Branch {#1123
          #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" => 1287894
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Тесты"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1124
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "136"
            "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 {#1125
              #items: array:1 [
                0 => App\Models\Book {#1048}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1126
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1287894
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Тесты"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1124}
            "field_page_start" => "136"
            "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 {#1125}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1126}
          ]
          #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 {#1127
          #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" => 1287895
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Первый уровень"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1128
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "136"
            "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" => []
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            "created_at" => "2026-04-10 13:58:26"
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                  #connection: "mysql"
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                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1101
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                    "id" => 5410
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                    "title" => "Условие"
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                  ]
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                    0 => "*"
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              ]
              #escapeWhenCastingToString: false
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            "task" => array:2 [
              "refs" => "1288858"
              "type" => "task"
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            "text" => "<p><strong>Т 1.5.</strong> Велосипедист проезжает середину подвесного моста со скоростью $36 \text{ км/ч}$. Мост прогнулся по дуге радиусом $20 \text{ м}$. С какой силой велосипед давит на мост, если общая масса велосипедиста и велосипеда $60 \text{ кг}$?</p><p><strong>А. </strong>$1200 \text{ Н}$.</p><p><strong>Б. </strong>$300 \text{ Н}$.</p><p><strong>В. </strong>$4,5 \text{ кН}$.</p><p><strong>Г. </strong>$600 \text{ Н}$.</p><p><strong>Д. </strong>Среди ответов А-Г нет правильного.</p>"
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                "height" => 371
                "path" => "/media/fizika_08/gelfgat-u/0-test1/5-1.webp?ts=1756050190"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1479355
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1097}
            "task" => array:2 [
              "refs" => "1288858"
              "type" => "task"
            ]
            "text" => "<p><strong>Т 1.5.</strong> Велосипедист проезжает середину подвесного моста со скоростью $36 \text{ км/ч}$. Мост прогнулся по дуге радиусом $20 \text{ м}$. С какой силой велосипед давит на мост, если общая масса велосипедиста и велосипеда $60 \text{ кг}$?</p><p><strong>А. </strong>$1200 \text{ Н}$.</p><p><strong>Б. </strong>$300 \text{ Н}$.</p><p><strong>В. </strong>$4,5 \text{ кН}$.</p><p><strong>Г. </strong>$600 \text{ Н}$.</p><p><strong>Д. </strong>Среди ответов А-Г нет правильного.</p>"
            "img" => array:1 [
              0 => array:5 [
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                "width" => "1483"
                "height" => 371
                "path" => "/media/fizika_08/gelfgat-u/0-test1/5-1.webp?ts=1756050190"
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          #hidden: []
          #visible: []
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            0 => "*"
          ]
        }
        1 => App\Models\Element {#1099
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
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          +preventsLazyLoading: false
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          +exists: true
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          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 1479634
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1087
              #items: array:1 [
                0 => App\Models\Edition {#1096
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
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                  #attributes: array:21 [
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                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1095
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                      #escapeWhenCastingToString: false
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                    "field_content_type" => "free"
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                    "field_page_content_mode" => ""
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                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1093
                      #items: []
                      #escapeWhenCastingToString: false
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                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1089
                      #items: []
                      #escapeWhenCastingToString: false
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                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1092
                      #items: []
                      #escapeWhenCastingToString: false
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                  ]
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                    "id" => 5411
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1095}
                    "field_content_type" => "free"
                    "field_content_mode" => "image"
                    "field_page_content_mode" => ""
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                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1093}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1089}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1092}
                    "field_content_source" => null
                  ]
                  #changes: []
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                  +timestamps: true
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                    0 => "*"
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              ]
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            "task" => array:2 [
              "refs" => "1288858"
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                "width" => "447"
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            "id" => 1479634
            "created_at" => "2026-04-10 13:58:26"
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            "edition" => Illuminate\Database\Eloquent\Collection {#1087}
            "task" => array:2 [
              "refs" => "1288858"
              "type" => "task"
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                "width" => "447"
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            "id" => 1738551
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1043
              #items: array:1 [
                0 => App\Models\Edition {#1090
                  #connection: "mysql"
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                    "id" => 6336
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение 2"
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                    "field_content_type" => "free"
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                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "2-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1086
                      #items: []
                      #escapeWhenCastingToString: false
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                      #items: []
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                    "id" => 6336
                    "created_at" => "2026-04-10 13:58:26"
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                    "title" => "Решение 2"
                    "field_order" => "3"
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              "type" => "task"
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            "text" => "<p><strong>Дано:</strong></p><p>$v = 36 \text{ км/ч}$</p><p>$R = 20 \text{ м}$</p><p>$m = 60 \text{ кг}$</p><p>Примем ускорение свободного падения $g \approx 10 \text{ м/с}^2$.</p><p><em>Перевод в систему СИ:</em></p><p>Скорость велосипедиста: $v = 36 \frac{\text{км}}{\text{ч}} = 36 \cdot \frac{1000 \text{ м}}{3600 \text{ с}} = 10 \frac{\text{м}}{\text{с}}$</p><p><strong>Найти:</strong></p><p>$\text{P}$ – сила, с которой велосипед давит на мост.</p><p><strong>Решение:</strong></p><p>Когда велосипедист проезжает самую низкую точку вогнутого моста, он движется по дуге окружности. На систему "велосипедист + велосипед" действуют две силы: сила тяжести $F_т = mg$, направленная вертикально вниз, и сила нормальной реакции опоры $\text{N}$, направленная вертикально вверх (к центру кривизны траектории).</p><p>Согласно второму закону Ньютона, равнодействующая этих сил равна произведению массы на центростремительное ускорение $a_ц$, которое также направлено вверх. Запишем уравнение второго закона Ньютона в проекции на вертикальную ось, направленную вверх:</p><p>$N - mg = ma_ц$</p><p>Центростремительное ускорение определяется по формуле:</p><p>$a_ц = \frac{v^2}{R}$</p><p>Подставим выражение для ускорения в уравнение сил:</p><p>$N - mg = m\frac{v^2}{R}$</p><p>Отсюда можно выразить силу реакции опоры $\text{N}$:</p><p>$N = mg + m\frac{v^2}{R} = m(g + \frac{v^2}{R})$</p><p>По третьему закону Ньютона, сила $\text{P}$, с которой велосипед давит на мост (его вес), равна по модулю силе реакции опоры $\text{N}$.</p><p>$P = N = m(g + \frac{v^2}{R})$</p><p>Теперь подставим числовые значения из условия задачи:</p><p>$P = 60 \text{ кг} \cdot (10 \frac{\text{м}}{\text{с}^2} + \frac{(10 \frac{\text{м}}{\text{с}})^2}{20 \text{ м}}) = 60 \cdot (10 + \frac{100}{20}) = 60 \cdot (10 + 5) = 60 \cdot 15 = 900 \text{ Н}$</p><p>Полученный результат 900 Н не соответствует ни одному из вариантов ответа А, Б, В, Г.</p><p><strong>Ответ:</strong></p><p>Д. Среди ответов А-Г нет правильного.</p>"
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            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1043}
            "task" => array:2 [
              "refs" => "1288858"
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            "text" => "<p><strong>Дано:</strong></p><p>$v = 36 \text{ км/ч}$</p><p>$R = 20 \text{ м}$</p><p>$m = 60 \text{ кг}$</p><p>Примем ускорение свободного падения $g \approx 10 \text{ м/с}^2$.</p><p><em>Перевод в систему СИ:</em></p><p>Скорость велосипедиста: $v = 36 \frac{\text{км}}{\text{ч}} = 36 \cdot \frac{1000 \text{ м}}{3600 \text{ с}} = 10 \frac{\text{м}}{\text{с}}$</p><p><strong>Найти:</strong></p><p>$\text{P}$ – сила, с которой велосипед давит на мост.</p><p><strong>Решение:</strong></p><p>Когда велосипедист проезжает самую низкую точку вогнутого моста, он движется по дуге окружности. На систему "велосипедист + велосипед" действуют две силы: сила тяжести $F_т = mg$, направленная вертикально вниз, и сила нормальной реакции опоры $\text{N}$, направленная вертикально вверх (к центру кривизны траектории).</p><p>Согласно второму закону Ньютона, равнодействующая этих сил равна произведению массы на центростремительное ускорение $a_ц$, которое также направлено вверх. Запишем уравнение второго закона Ньютона в проекции на вертикальную ось, направленную вверх:</p><p>$N - mg = ma_ц$</p><p>Центростремительное ускорение определяется по формуле:</p><p>$a_ц = \frac{v^2}{R}$</p><p>Подставим выражение для ускорения в уравнение сил:</p><p>$N - mg = m\frac{v^2}{R}$</p><p>Отсюда можно выразить силу реакции опоры $\text{N}$:</p><p>$N = mg + m\frac{v^2}{R} = m(g + \frac{v^2}{R})$</p><p>По третьему закону Ньютона, сила $\text{P}$, с которой велосипед давит на мост (его вес), равна по модулю силе реакции опоры $\text{N}$.</p><p>$P = N = m(g + \frac{v^2}{R})$</p><p>Теперь подставим числовые значения из условия задачи:</p><p>$P = 60 \text{ кг} \cdot (10 \frac{\text{м}}{\text{с}^2} + \frac{(10 \frac{\text{м}}{\text{с}})^2}{20 \text{ м}}) = 60 \cdot (10 + \frac{100}{20}) = 60 \cdot (10 + 5) = 60 \cdot 15 = 900 \text{ Н}$</p><p>Полученный результат 900 Н не соответствует ни одному из вариантов ответа А, Б, В, Г.</p><p><strong>Ответ:</strong></p><p>Д. Среди ответов А-Г нет правильного.</p>"
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                2 => App\Models\Task {#1233
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                3 => App\Models\Task {#1238
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                4 => App\Models\Task {#1252
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                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1249 …2}
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№1.5 (с. 137)
Условие. №1.5 (с. 137)
скриншот условия
Физика, 8-11 класс Учебник, задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2005, страница 137, номер 1.5, Условие

Т 1.5. Велосипедист проезжает середину подвесного моста со скоростью $36 \text{ км/ч}$. Мост прогнулся по дуге радиусом $20 \text{ м}$. С какой силой велосипед давит на мост, если общая масса велосипедиста и велосипеда $60 \text{ кг}$?

А. $1200 \text{ Н}$.

Б. $300 \text{ Н}$.

В. $4,5 \text{ кН}$.

Г. $600 \text{ Н}$.

Д. Среди ответов А-Г нет правильного.

Решение. №1.5 (с. 137)
Физика, 8-11 класс Учебник, задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2005, страница 137, номер 1.5, Решение
Решение 2. №1.5 (с. 137)

Дано:

$v = 36 \text{ км/ч}$

$R = 20 \text{ м}$

$m = 60 \text{ кг}$

Примем ускорение свободного падения $g \approx 10 \text{ м/с}^2$.

Перевод в систему СИ:

Скорость велосипедиста: $v = 36 \frac{\text{км}}{\text{ч}} = 36 \cdot \frac{1000 \text{ м}}{3600 \text{ с}} = 10 \frac{\text{м}}{\text{с}}$

Найти:

$\text{P}$ – сила, с которой велосипед давит на мост.

Решение:

Когда велосипедист проезжает самую низкую точку вогнутого моста, он движется по дуге окружности. На систему "велосипедист + велосипед" действуют две силы: сила тяжести $F_т = mg$, направленная вертикально вниз, и сила нормальной реакции опоры $\text{N}$, направленная вертикально вверх (к центру кривизны траектории).

Согласно второму закону Ньютона, равнодействующая этих сил равна произведению массы на центростремительное ускорение $a_ц$, которое также направлено вверх. Запишем уравнение второго закона Ньютона в проекции на вертикальную ось, направленную вверх:

$N - mg = ma_ц$

Центростремительное ускорение определяется по формуле:

$a_ц = \frac{v^2}{R}$

Подставим выражение для ускорения в уравнение сил:

$N - mg = m\frac{v^2}{R}$

Отсюда можно выразить силу реакции опоры $\text{N}$:

$N = mg + m\frac{v^2}{R} = m(g + \frac{v^2}{R})$

По третьему закону Ньютона, сила $\text{P}$, с которой велосипед давит на мост (его вес), равна по модулю силе реакции опоры $\text{N}$.

$P = N = m(g + \frac{v^2}{R})$

Теперь подставим числовые значения из условия задачи:

$P = 60 \text{ кг} \cdot (10 \frac{\text{м}}{\text{с}^2} + \frac{(10 \frac{\text{м}}{\text{с}})^2}{20 \text{ м}}) = 60 \cdot (10 + \frac{100}{20}) = 60 \cdot (10 + 5) = 60 \cdot 15 = 900 \text{ Н}$

Полученный результат 900 Н не соответствует ни одному из вариантов ответа А, Б, В, Г.

Ответ:

Д. Среди ответов А-Г нет правильного.

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