Вариант 9, страница 83 - гдз по физике 9 класс дидактические материалы Марон, Марон

Физика, 9 класс Дидактические материалы, авторы: Марон Абрам Евсеевич, Марон Евгений Абрамович, издательство Просвещение, Москва, 2022, белого цвета

Авторы: Марон А. Е., Марон Е. А.

Тип: Дидактические материалы

Издательство: Просвещение

Год издания: 2022 - 2026

Уровень обучения: базовый

Цвет обложки: белый изображена башня

ISBN: 978-5-09-111414-0

Самостоятельные работы. СР-13. Механические волны. Звук - страница 83.

App\Models\Task {#1024 // resources/views/models/task/default.blade.php
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  #table: "tasks"
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  #with: []
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  #escapeWhenCastingToString: false
  #attributes: array:24 [
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    "created_at" => "2026-04-10 13:58:26"
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    "field_page_end" => null
    "field_url" => "/9-klass/fizika/maron-didakticheskie-materialy/cp13-9"
    "field_display_title" => "Вариант 9"
    "field_outside_task" => null
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      #items: []
      #escapeWhenCastingToString: false
    }
    "field_metatags_title" => null
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      #items: []
      #escapeWhenCastingToString: false
    }
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      #items: array:1 [
        0 => App\Models\Branch {#342
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
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          #attributes: array:24 [
            "id" => 1428174
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
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              #items: array:1 [
                0 => App\Models\Book {#1033
                  #connection: "mysql"
                  #table: "books"
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                              "field_accusative_case" => "базовый"
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                              "field_dative_case" => "базовому"
                              "field_genitive_case" => "базового"
                              "field_nominative_case" => "базовый"
                              "field_prepositional_case" => "базовом"
                            ]
                            "field_translit" => "bazovyy"
                          ]
                          #original: array:6 [
                            "id" => 38
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "базовый"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "базовый"
                              "field_creative_case" => "базовым"
                              "field_dative_case" => "базовому"
                              "field_genitive_case" => "базового"
                              "field_nominative_case" => "базовый"
                              "field_prepositional_case" => "базовом"
                            ]
                            "field_translit" => "bazovyy"
                          ]
                          #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_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1052
                      #items: array:1 [
                        0 => 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:10 [
                            "id" => 25
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "ФГОС (новый)"
                            "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_color" => "красный"
                            "field_end_year" => "2027"
                            "field_start_year" => "2023"
                            "field_translit" => "fgos"
                            "field_type" => "новый"
                          ]
                          #original: array:10 [
                            "id" => 25
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "ФГОС (новый)"
                            "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_color" => "красный"
                            "field_end_year" => "2027"
                            "field_start_year" => "2023"
                            "field_translit" => "fgos"
                            "field_type" => "новый"
                          ]
                          #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_publication_number" => "3"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1054
                      #items: array:1 [
                        0 => 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" => 34
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "переработанное"
                            "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" => "pererabotannoe"
                          ]
                          #original: array:6 [
                            "id" => 34
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "переработанное"
                            "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" => "pererabotannoe"
                          ]
                          #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 {#1056
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "изображена башня"
                    "field_publication_year" => "2022"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное пособие"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "674"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/maron-dm/"
                    "field_isbn" => "978-5-09-111414-0"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_09/maron-dm/covers/cover1.webp?ts=1758533880"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/maron-dm/covers/cover1.webp?ts=1758533880"
                        "alt" => ""
                        "width" => "1888"
                        "height" => "2427"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1057
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1058
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1059
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/9-klass/fizika/maron-didakticheskie-materialy"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1060
                      #items: array:1 [
                        0 => 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:6 [
                            "id" => 45
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "белый"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "белый"
                              "field_creative_case" => "белым"
                              "field_dative_case" => "белому"
                              "field_genitive_case" => "белого"
                              "field_nominative_case" => "белый"
                              "field_prepositional_case" => "белом"
                            ]
                            "field_translit" => "belyy"
                          ]
                          #original: array:6 [
                            "id" => 45
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "белый"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "белый"
                              "field_creative_case" => "белым"
                              "field_dative_case" => "белому"
                              "field_genitive_case" => "белого"
                              "field_nominative_case" => "белый"
                              "field_prepositional_case" => "белом"
                            ]
                            "field_translit" => "belyy"
                          ]
                          #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" => 894
                    "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 {#1030}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1034}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1036}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1038}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1041}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1042}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1044}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1046}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1048}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1049}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1050}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1052}
                    "field_publication_number" => "3"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1054}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1056}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "изображена башня"
                    "field_publication_year" => "2022"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное пособие"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "674"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/maron-dm/"
                    "field_isbn" => "978-5-09-111414-0"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_09/maron-dm/covers/cover1.webp?ts=1758533880"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/maron-dm/covers/cover1.webp?ts=1758533880"
                        "alt" => ""
                        "width" => "1888"
                        "height" => "2427"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1057}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1058}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1059}
                    "field_url" => "/9-klass/fizika/maron-didakticheskie-materialy"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1060}
                    "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 {#1062
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1428174
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Самостоятельные работы"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1023}
            "field_page_start" => "53"
            "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 {#333}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1062}
          ]
          #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 {#1063
      #items: array:2 [
        0 => App\Models\Branch {#342}
        1 => App\Models\Branch {#1064
          #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" => 1428187
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "СР-13. Механические волны. Звук"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1065
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "81"
            "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 {#1066
              #items: array:1 [
                0 => App\Models\Book {#1033}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1067
              #items: array:1 [
                0 => App\Models\Branch {#1068
                  #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" => 1428174
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Самостоятельные работы"
                    "field_branch_order" => null
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1069
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_page_start" => "53"
                    "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 {#1070
                      #items: array:1 [
                        0 => App\Models\Book {#1071
                          #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 [ …50]
                          #original: array:50 [ …50]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [ …1]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1102
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                  ]
                  #original: array:24 [
                    "id" => 1428174
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Самостоятельные работы"
                    "field_branch_order" => null
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1069}
                    "field_page_start" => "53"
                    "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 {#1070}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1102}
                  ]
                  #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" => 1428187
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "СР-13. Механические волны. Звук"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1065}
            "field_page_start" => "81"
            "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 {#1066}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1067}
          ]
          #changes: []
          #casts: []
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    "content" => Illuminate\Database\Eloquent\Collection {#1103
      #items: array:2 [
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          #connection: "mysql"
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            "id" => 1682999
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1105
              #items: array:1 [
                0 => App\Models\Edition {#1106
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
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                    "id" => 5992
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
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                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1107
                      #items: array:1 [
                        0 => App\Models\Term {#1108
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
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                          #attributes: array:6 [ …6]
                          #original: array:6 [ …6]
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                          #guarded: array:1 [ …1]
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                    "field_content_type" => "free"
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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 {#1109
                      #items: []
                      #escapeWhenCastingToString: false
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                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1110
                      #items: []
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                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1111
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                  #original: array:21 [
                    "id" => 5992
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1107}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
                    "field_content_text_checked" => null
                    "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 {#1109}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1110}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1111}
                    "field_content_source" => null
                  ]
                  #changes: []
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              #escapeWhenCastingToString: false
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            "task" => array:2 [
              "refs" => "1428684"
              "type" => "task"
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            "text" => "<p><strong>1.</strong> Если ударить молотком по одному концу длинной металлической трубы, то стоящий у другого конца трубы услышит двойной удар. Почему?</p><p><strong>2.</strong> Теплоход, движущийся со скоростью $5.5 \text{ м/с}$, дал гудок, звук которого услышали на мосту через $3 \text{ с}$. Спустя $3 \text{ мин}$ теплоход прошёл под мостом. Определите скорость звука в воздухе.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "9-1.jpg"
                "alt" => null
                "width" => "1433"
                "height" => 469
                "path" => "/media/fizika_09/maron-dm/0-cp13/9-1.webp?ts=1758964248"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1682999
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1105}
            "task" => array:2 [
              "refs" => "1428684"
              "type" => "task"
            ]
            "text" => "<p><strong>1.</strong> Если ударить молотком по одному концу длинной металлической трубы, то стоящий у другого конца трубы услышит двойной удар. Почему?</p><p><strong>2.</strong> Теплоход, движущийся со скоростью $5.5 \text{ м/с}$, дал гудок, звук которого услышали на мосту через $3 \text{ с}$. Спустя $3 \text{ мин}$ теплоход прошёл под мостом. Определите скорость звука в воздухе.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "9-1.jpg"
                "alt" => null
                "width" => "1433"
                "height" => 469
                "path" => "/media/fizika_09/maron-dm/0-cp13/9-1.webp?ts=1758964248"
              ]
            ]
          ]
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            0 => "*"
          ]
        }
        1 => App\Models\Element {#1112
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
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          #perPage: 15
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          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 1730701
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1113
              #items: array:1 [
                0 => App\Models\Edition {#1114
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
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                  #withCount: []
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                  #perPage: 15
                  +exists: true
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                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 6313
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1115
                      #items: array:1 [
                        0 => App\Models\Term {#1116
                          #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 [ …6]
                          #original: array:6 [ …6]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
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                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [ …1]
                        }
                      ]
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                    }
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
                    "field_page_content_mode" => ""
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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" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1117
                      #items: []
                      #escapeWhenCastingToString: false
                    }
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                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1118
                      #items: []
                      #escapeWhenCastingToString: false
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                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1119
                      #items: []
                      #escapeWhenCastingToString: false
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                  #original: array:21 [
                    "id" => 6313
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1115}
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
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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" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1117}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1118}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1119}
                    "field_content_source" => null
                  ]
                  #changes: []
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                  #attributeCastCache: []
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                  #appends: []
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                  +timestamps: true
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                  #guarded: array:1 [
                    0 => "*"
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              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1428684"
              "type" => "task"
            ]
            "text" => "<p><strong>1.</strong> Двойной удар слышен потому, что звук от удара молотком распространяется до наблюдателя по двум разным средам с разной скоростью: по металлу трубы и по воздуху внутри нее. Скорость распространения звука в твёрдых телах (в данном случае, в металле) значительно выше, чем в газах (в воздухе). Поэтому звук, идущий по металлической трубе, достигает уха наблюдателя первым. Звук, распространяющийся по воздуху, приходит вторым, с некоторой задержкой. В результате этого человек на другом конце трубы воспринимает два отдельных звуковых сигнала, что и создаёт эффект двойного удара.</p><p><strong>Ответ:</strong> Звук распространяется по металлу трубы и по воздуху с разной скоростью. Сначала до наблюдателя доходит звук, прошедший по металлу, а затем — звук, прошедший по воздуху.</p><p><strong>2.</strong> <strong>Дано</strong></p><p>$v_т = 5,5 \text{ м/с}$<br>$t_1 = 3 \text{ с}$<br>$t_2 = 3 \text{ мин} = 3 \cdot 60 \text{ с} = 180 \text{ с}$</p><p><strong>Найти:</strong></p><p>$v_{зв}$ — ?</p><p><strong>Решение</strong></p><p>Пусть $\text{S}$ — расстояние от теплохода до моста в тот момент, когда был дан гудок.Звук от гудка преодолевает это расстояние за время $t_1$. Следовательно, расстояние можно выразить через скорость звука $v_{зв}$:<br>$S = v_{зв} \cdot t_1$</p><p>Сам теплоход, двигаясь со скоростью $v_т$, проходит то же самое расстояние $\text{S}$ до моста за время $t_2$. Таким образом, это же расстояние можно выразить через скорость теплохода:<br>$S = v_т \cdot t_2$</p><p>Так как в обоих уравнениях расстояние $\text{S}$ одно и то же, мы можем приравнять правые части этих выражений:<br>$v_{зв} \cdot t_1 = v_т \cdot t_2$</p><p>Теперь выразим искомую скорость звука $v_{зв}$ из этого равенства:<br>$v_{зв} = \frac{v_т \cdot t_2}{t_1}$</p><p>Подставим числовые значения в полученную формулу:<br>$v_{зв} = \frac{5,5 \text{ м/с} \cdot 180 \text{ с}}{3 \text{ с}} = 5,5 \cdot 60 \text{ м/с} = 330 \text{ м/с}$</p><p><strong>Ответ:</strong> скорость звука в воздухе равна 330 м/с.</p>"
          ]
          #original: array:6 [
            "id" => 1730701
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1113}
            "task" => array:2 [
              "refs" => "1428684"
              "type" => "task"
            ]
            "text" => "<p><strong>1.</strong> Двойной удар слышен потому, что звук от удара молотком распространяется до наблюдателя по двум разным средам с разной скоростью: по металлу трубы и по воздуху внутри нее. Скорость распространения звука в твёрдых телах (в данном случае, в металле) значительно выше, чем в газах (в воздухе). Поэтому звук, идущий по металлической трубе, достигает уха наблюдателя первым. Звук, распространяющийся по воздуху, приходит вторым, с некоторой задержкой. В результате этого человек на другом конце трубы воспринимает два отдельных звуковых сигнала, что и создаёт эффект двойного удара.</p><p><strong>Ответ:</strong> Звук распространяется по металлу трубы и по воздуху с разной скоростью. Сначала до наблюдателя доходит звук, прошедший по металлу, а затем — звук, прошедший по воздуху.</p><p><strong>2.</strong> <strong>Дано</strong></p><p>$v_т = 5,5 \text{ м/с}$<br>$t_1 = 3 \text{ с}$<br>$t_2 = 3 \text{ мин} = 3 \cdot 60 \text{ с} = 180 \text{ с}$</p><p><strong>Найти:</strong></p><p>$v_{зв}$ — ?</p><p><strong>Решение</strong></p><p>Пусть $\text{S}$ — расстояние от теплохода до моста в тот момент, когда был дан гудок.Звук от гудка преодолевает это расстояние за время $t_1$. Следовательно, расстояние можно выразить через скорость звука $v_{зв}$:<br>$S = v_{зв} \cdot t_1$</p><p>Сам теплоход, двигаясь со скоростью $v_т$, проходит то же самое расстояние $\text{S}$ до моста за время $t_2$. Таким образом, это же расстояние можно выразить через скорость теплохода:<br>$S = v_т \cdot t_2$</p><p>Так как в обоих уравнениях расстояние $\text{S}$ одно и то же, мы можем приравнять правые части этих выражений:<br>$v_{зв} \cdot t_1 = v_т \cdot t_2$</p><p>Теперь выразим искомую скорость звука $v_{зв}$ из этого равенства:<br>$v_{зв} = \frac{v_т \cdot t_2}{t_1}$</p><p>Подставим числовые значения в полученную формулу:<br>$v_{зв} = \frac{5,5 \text{ м/с} \cdot 180 \text{ с}}{3 \text{ с}} = 5,5 \cdot 60 \text{ м/с} = 330 \text{ м/с}$</p><p><strong>Ответ:</strong> скорость звука в воздухе равна 330 м/с.</p>"
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        0 => App\Models\Book {#1033}
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            "created_at" => "2026-04-10 13:58:26"
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            "field_display_title" => "83"
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              #items: array:1 [
                0 => App\Models\Book {#1146
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
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                  #perPage: 15
                  +exists: true
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                  #attributes: array:50 [
                    "id" => 894
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
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                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1148
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                          #connection: "mysql"
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                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [ …10]
                          #original: array:10 [ …10]
                          #changes: []
                          #casts: []
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                           …12
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                      #items: array:1 [
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                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1153
                      #items: array:2 [
                        0 => App\Models\Term {#1154 …30}
                        1 => App\Models\Term {#1155 …30}
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                      #escapeWhenCastingToString: false
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                      #items: []
                      #escapeWhenCastingToString: false
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                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1157
                      #items: array:1 [
                        0 => App\Models\Term {#1158 …30}
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1159
                      #items: array:1 [
                        0 => App\Models\Term {#1160 …30}
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                      ]
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                        1 => App\Models\Branch {#1633 …30}
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                1 => App\Models\Task {#1721
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                        1 => App\Models\Branch {#1633 …30}
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                2 => App\Models\Task {#1744
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                        0 => App\Models\Branch {#1597 …30}
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                    }
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                        1 => App\Models\Branch {#1633 …30}
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                        1 => App\Models\Element {#1758 …30}
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Вариант 9 (с. 83)
Условие. Вариант 9 (с. 83)
скриншот условия
Физика, 9 класс Дидактические материалы, авторы: Марон Абрам Евсеевич, Марон Евгений Абрамович, издательство Просвещение, Москва, 2022, белого цвета, страница 83, Условие

1. Если ударить молотком по одному концу длинной металлической трубы, то стоящий у другого конца трубы услышит двойной удар. Почему?

2. Теплоход, движущийся со скоростью $5.5 \text{ м/с}$, дал гудок, звук которого услышали на мосту через $3 \text{ с}$. Спустя $3 \text{ мин}$ теплоход прошёл под мостом. Определите скорость звука в воздухе.

Решение. Вариант 9 (с. 83)

1. Двойной удар слышен потому, что звук от удара молотком распространяется до наблюдателя по двум разным средам с разной скоростью: по металлу трубы и по воздуху внутри нее. Скорость распространения звука в твёрдых телах (в данном случае, в металле) значительно выше, чем в газах (в воздухе). Поэтому звук, идущий по металлической трубе, достигает уха наблюдателя первым. Звук, распространяющийся по воздуху, приходит вторым, с некоторой задержкой. В результате этого человек на другом конце трубы воспринимает два отдельных звуковых сигнала, что и создаёт эффект двойного удара.

Ответ: Звук распространяется по металлу трубы и по воздуху с разной скоростью. Сначала до наблюдателя доходит звук, прошедший по металлу, а затем — звук, прошедший по воздуху.

2. Дано

$v_т = 5,5 \text{ м/с}$
$t_1 = 3 \text{ с}$
$t_2 = 3 \text{ мин} = 3 \cdot 60 \text{ с} = 180 \text{ с}$

Найти:

$v_{зв}$ — ?

Решение

Пусть $\text{S}$ — расстояние от теплохода до моста в тот момент, когда был дан гудок.Звук от гудка преодолевает это расстояние за время $t_1$. Следовательно, расстояние можно выразить через скорость звука $v_{зв}$:
$S = v_{зв} \cdot t_1$

Сам теплоход, двигаясь со скоростью $v_т$, проходит то же самое расстояние $\text{S}$ до моста за время $t_2$. Таким образом, это же расстояние можно выразить через скорость теплохода:
$S = v_т \cdot t_2$

Так как в обоих уравнениях расстояние $\text{S}$ одно и то же, мы можем приравнять правые части этих выражений:
$v_{зв} \cdot t_1 = v_т \cdot t_2$

Теперь выразим искомую скорость звука $v_{зв}$ из этого равенства:
$v_{зв} = \frac{v_т \cdot t_2}{t_1}$

Подставим числовые значения в полученную формулу:
$v_{зв} = \frac{5,5 \text{ м/с} \cdot 180 \text{ с}}{3 \text{ с}} = 5,5 \cdot 60 \text{ м/с} = 330 \text{ м/с}$

Ответ: скорость звука в воздухе равна 330 м/с.

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