Номер 2, страница 207 - гдз по физике 9 класс учебник Грачев, Погожев

Физика, 9 класс Учебник, авторы: Грачев Александр Васильевич, Погожев Владимир Александрович, Боков Павел Юрьевич, издательство Вентана-граф, Москва, 2012

Авторы: Грачев А. В., Погожев В. А., Боков П. Ю.

Тип: Учебник

Серия: алгоритм успеха

Издательство: Вентана-граф

Год издания: 2012 - 2026

Цвет обложки: синий изображено здание и радуга

ISBN: 978-5-360-07412-0

Глава 6. Механические колебания и волны. Параграф 32. Преобразование энергии при механических колебаниях. Вопросы - номер 2, страница 207.

App\Models\Task {#1024 // resources/views/models/task/default.blade.php
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      #items: array:1 [
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                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1049
                      #items: array:1 [
                        0 => App\Models\Term {#1050
                          #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"
                          ]
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                          #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 {#1051
                      #items: array:1 [
                        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:8 [
                            "id" => 4697
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "алгоритм успеха"
                            "field_cases" => null
                            "field_foreign_lang_series" => null
                            "field_transcription_eng" => null
                            "field_translit" => "algoritm uspekha"
                          ]
                          #original: array:8 [
                            "id" => 4697
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "алгоритм успеха"
                            "field_cases" => null
                            "field_foreign_lang_series" => null
                            "field_transcription_eng" => null
                            "field_translit" => "algoritm uspekha"
                          ]
                          #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_umk" => Illuminate\Database\Eloquent\Collection {#1053
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1054
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1055
                      #items: array:1 [
                        0 => App\Models\Term {#1056
                          #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" => 6706
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "ФГОС (старый)"
                            "field_cases" => array:6 [ …6]
                            "field_color" => null
                            "field_end_year" => "2022"
                            "field_start_year" => "2019"
                            "field_translit" => "fgos-old"
                            "field_type" => null
                          ]
                          #original: array:10 [
                            "id" => 6706
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "ФГОС (старый)"
                            "field_cases" => array:6 [ …6]
                            "field_color" => null
                            "field_end_year" => "2022"
                            "field_start_year" => "2019"
                            "field_translit" => "fgos-old"
                            "field_type" => 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_publication_number" => "2"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1057
                      #items: array:1 [
                        0 => App\Models\Term {#1058
                          #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" => 6900
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "доработанное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "dorabotannoe"
                          ]
                          #original: array:6 [
                            "id" => 6900
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "доработанное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "dorabotannoe"
                          ]
                          #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 {#1059
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "изображено здание и радуга"
                    "field_publication_year" => "2012"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для учащихся общеобразовательных организаций"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "580"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/grachev-u/"
                    "field_isbn" => "978-5-360-07412-0"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_09/grachev-u/covers/cover1.webp?ts=1759082140"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/grachev-u/covers/cover1.webp?ts=1759082140"
                        "alt" => ""
                        "width" => "2294"
                        "height" => "3039"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1060
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1061
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1062
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/9-klass/fizika/grachev-uchebnik"
                    "field_cover_color" => 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: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" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
                  #original: array:50 [
                    "id" => 1202
                    "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 {#1034}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1036}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1038}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1040}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1044}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1045}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1047}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1049}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1051}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1053}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1054}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1055}
                    "field_publication_number" => "2"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1057}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1059}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "изображено здание и радуга"
                    "field_publication_year" => "2012"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для учащихся общеобразовательных организаций"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "580"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/grachev-u/"
                    "field_isbn" => "978-5-360-07412-0"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_09/grachev-u/covers/cover1.webp?ts=1759082140"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/grachev-u/covers/cover1.webp?ts=1759082140"
                        "alt" => ""
                        "width" => "2294"
                        "height" => "3039"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1060}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1061}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1062}
                    "field_url" => "/9-klass/fizika/grachev-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1063}
                    "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 {#1065
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1437956
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Механические колебания и волны"
            "field_branch_order" => "6"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#333}
            "field_page_start" => "194"
            "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 {#1030}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1065}
          ]
          #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 {#1066
      #items: array:3 [
        0 => App\Models\Branch {#1023}
        1 => App\Models\Branch {#1067
          #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" => 1437960
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Преобразование энергии при механических колебаниях"
            "field_branch_order" => "32"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1068
              #items: array:1 [
                0 => App\Models\Term {#1069
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Параграф"
                      "field_creative_case" => "Параграфом"
                      "field_dative_case" => "Параграфу"
                      "field_genitive_case" => "Параграфа"
                      "field_nominative_case" => "Параграф"
                      "field_prepositional_case" => "Параграфе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #original: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Параграф"
                      "field_creative_case" => "Параграфом"
                      "field_dative_case" => "Параграфу"
                      "field_genitive_case" => "Параграфа"
                      "field_nominative_case" => "Параграф"
                       …1
                    ]
                    "field_page_check_not_needed" => null
                    "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_page_start" => "202"
            "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 {#1032}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1071
              #items: array:1 [
                0 => App\Models\Branch {#1072
                  #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" => 1437956
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Механические колебания и волны"
                    "field_branch_order" => "6"
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1073 …2}
                    "field_page_start" => "194"
                    "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 {#1074 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1075 …2}
                  ]
                  #original: array:24 [
                    "id" => 1437956
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Механические колебания и волны"
                    "field_branch_order" => "6"
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1073 …2}
                    "field_page_start" => "194"
                    "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 {#1074 …2}
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            "field_branch_order" => "32"
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        2 => App\Models\Branch {#1076
          #connection: "mysql"
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                0 => App\Models\Branch {#1080
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                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1081 …2}
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                    "book" => Illuminate\Database\Eloquent\Collection {#1082 …2}
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                    "id" => 1437960
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                    "book" => Illuminate\Database\Eloquent\Collection {#1082 …2}
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            "id" => 1437961
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            "field_display_title" => "Вопросы"
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            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1077}
            "field_page_start" => "207"
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    "content" => Illuminate\Database\Eloquent\Collection {#1084
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          #attributes: array:7 [
            "id" => 1705209
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            "edition" => Illuminate\Database\Eloquent\Collection {#1086
              #items: array:1 [
                0 => App\Models\Edition {#1087
                  #connection: "mysql"
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                  #attributes: array:21 [
                    "id" => 6112
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1088 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
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                    "field_moderator" => "stas"
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                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1090 …2}
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                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1092 …2}
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                  #original: array:21 [
                    "id" => 6112
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1088 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
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                    "field_content_text_checked" => "0"
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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 {#1090 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1091 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1092 …2}
                    "field_content_source" => null
                  ]
                  #changes: []
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                    0 => "*"
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                }
              ]
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            }
            "task" => array:2 [
              "refs" => "1438315"
              "type" => "task"
            ]
            "text" => "<p><strong>2.</strong> Как изменяются с течением времени потенциальная и кинетическая энергии пружинного маятника при свободных гармонических колебаниях?</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "2-1.jpg"
                "alt" => null
                "width" => "487"
                "height" => 105
                "path" => "/media/fizika_09/grachev-u/0-32vopr/2-1.webp?ts=1759503163"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1705209
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            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1086}
            "task" => array:2 [
              "refs" => "1438315"
              "type" => "task"
            ]
            "text" => "<p><strong>2.</strong> Как изменяются с течением времени потенциальная и кинетическая энергии пружинного маятника при свободных гармонических колебаниях?</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "2-1.jpg"
                "alt" => null
                "width" => "487"
                "height" => 105
                "path" => "/media/fizika_09/grachev-u/0-32vopr/2-1.webp?ts=1759503163"
              ]
            ]
          ]
          #changes: []
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          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Element {#1093
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
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          +exists: true
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          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 1812893
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1094
              #items: array:1 [
                0 => App\Models\Edition {#1095
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
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                  #attributes: array:21 [
                    "id" => 6644
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1096 …2}
                    "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 {#1098 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1099 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1100 …2}
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                  ]
                  #original: array:21 [
                    "id" => 6644
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
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                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1098 …2}
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                  ]
                  #changes: []
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                  #attributeCastCache: []
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                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
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                  #visible: []
                  #fillable: []
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                    0 => "*"
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              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1438315"
              "type" => "task"
            ]
            "text" => "<p><strong>Решение</strong></p><p>При свободных гармонических колебаниях пружинного маятника происходит непрерывное превращение энергии из одного вида в другой: из потенциальной в кинетическую и обратно. В идеальной системе без трения полная механическая энергия, являющаяся суммой потенциальной и кинетической энергий, остается постоянной.</p><p>Потенциальная энергия ($E_п$) пружинного маятника — это энергия упругой деформации пружины, которая зависит от смещения груза $\text{x}$ от положения равновесия и жесткости пружины $\text{k}$: $E_п = \frac{kx^2}{2}$. Эта энергия достигает своего максимального значения в точках максимального смещения (в крайних положениях, где $x = \pm A$, а $\text{A}$ — амплитуда), так как в этих точках деформация пружины наибольшая. В положении равновесия ($x = 0$) пружина не деформирована, и потенциальная энергия равна нулю.</p><p>Кинетическая энергия ($E_к$) маятника — это энергия движения его груза массой $\text{m}$ со скоростью $\text{v}$: $E_к = \frac{mv^2}{2}$. Эта энергия максимальна, когда маятник проходит положение равновесия ($x = 0$), так как в этой точке его скорость наибольшая. В крайних точках маятник на мгновение останавливается, его скорость становится равной нулю ($v = 0$), и кинетическая энергия в эти моменты также равна нулю.</p><p>Таким образом, процесс изменения энергий можно описать как непрерывный переход. В крайних точках вся энергия системы является потенциальной ($E = E_{п_{max}}$). По мере движения к положению равновесия потенциальная энергия уменьшается и преобразуется в кинетическую, которая возрастает. В положении равновесия вся энергия системы становится кинетической ($E = E_{к_{max}}$). Затем, при движении к другой крайней точке, кинетическая энергия снова преобразуется в потенциальную. Эти превращения происходят периодически и в противофазе: максимум одной энергии совпадает с минимумом (нулем) другой.</p><p>Математически, если координата маятника меняется по закону $x(t) = A \cos(\omega t)$, то зависимости энергий от времени выглядят так:$E_п(t) = \frac{kA^2}{2} \cos^2(\omega t)$ и $E_к(t) = \frac{kA^2}{2} \sin^2(\omega t)$.Их сумма, полная энергия $E = E_п + E_к = \frac{kA^2}{2}(\cos^2(\omega t) + \sin^2(\omega t)) = \frac{kA^2}{2}$, остается постоянной.</p><p><strong>Ответ:</strong></p><p>При свободных гармонических колебаниях пружинного маятника его потенциальная и кинетическая энергии периодически изменяются, переходя друг в друга. Потенциальная энергия максимальна в крайних точках траектории и равна нулю в положении равновесия. Кинетическая энергия, наоборот, максимальна в положении равновесия и равна нулю в крайних точках. Сумма потенциальной и кинетической энергий (полная механическая энергия) маятника остается постоянной.</p>"
          ]
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            "created_at" => "2026-04-10 13:58:26"
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            "edition" => Illuminate\Database\Eloquent\Collection {#1094}
            "task" => array:2 [
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            "text" => "<p><strong>Решение</strong></p><p>При свободных гармонических колебаниях пружинного маятника происходит непрерывное превращение энергии из одного вида в другой: из потенциальной в кинетическую и обратно. В идеальной системе без трения полная механическая энергия, являющаяся суммой потенциальной и кинетической энергий, остается постоянной.</p><p>Потенциальная энергия ($E_п$) пружинного маятника — это энергия упругой деформации пружины, которая зависит от смещения груза $\text{x}$ от положения равновесия и жесткости пружины $\text{k}$: $E_п = \frac{kx^2}{2}$. Эта энергия достигает своего максимального значения в точках максимального смещения (в крайних положениях, где $x = \pm A$, а $\text{A}$ — амплитуда), так как в этих точках деформация пружины наибольшая. В положении равновесия ($x = 0$) пружина не деформирована, и потенциальная энергия равна нулю.</p><p>Кинетическая энергия ($E_к$) маятника — это энергия движения его груза массой $\text{m}$ со скоростью $\text{v}$: $E_к = \frac{mv^2}{2}$. Эта энергия максимальна, когда маятник проходит положение равновесия ($x = 0$), так как в этой точке его скорость наибольшая. В крайних точках маятник на мгновение останавливается, его скорость становится равной нулю ($v = 0$), и кинетическая энергия в эти моменты также равна нулю.</p><p>Таким образом, процесс изменения энергий можно описать как непрерывный переход. В крайних точках вся энергия системы является потенциальной ($E = E_{п_{max}}$). По мере движения к положению равновесия потенциальная энергия уменьшается и преобразуется в кинетическую, которая возрастает. В положении равновесия вся энергия системы становится кинетической ($E = E_{к_{max}}$). Затем, при движении к другой крайней точке, кинетическая энергия снова преобразуется в потенциальную. Эти превращения происходят периодически и в противофазе: максимум одной энергии совпадает с минимумом (нулем) другой.</p><p>Математически, если координата маятника меняется по закону $x(t) = A \cos(\omega t)$, то зависимости энергий от времени выглядят так:$E_п(t) = \frac{kA^2}{2} \cos^2(\omega t)$ и $E_к(t) = \frac{kA^2}{2} \sin^2(\omega t)$.Их сумма, полная энергия $E = E_п + E_к = \frac{kA^2}{2}(\cos^2(\omega t) + \sin^2(\omega t)) = \frac{kA^2}{2}$, остается постоянной.</p><p><strong>Ответ:</strong></p><p>При свободных гармонических колебаниях пружинного маятника его потенциальная и кинетическая энергии периодически изменяются, переходя друг в друга. Потенциальная энергия максимальна в крайних точках траектории и равна нулю в положении равновесия. Кинетическая энергия, наоборот, максимальна в положении равновесия и равна нулю в крайних точках. Сумма потенциальной и кинетической энергий (полная механическая энергия) маятника остается постоянной.</p>"
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№2 (с. 207)
Условие. №2 (с. 207)
скриншот условия
Физика, 9 класс Учебник, авторы: Грачев Александр Васильевич, Погожев Владимир Александрович, Боков Павел Юрьевич, издательство Вентана-граф, Москва, 2012, страница 207, номер 2, Условие

2. Как изменяются с течением времени потенциальная и кинетическая энергии пружинного маятника при свободных гармонических колебаниях?

Решение. №2 (с. 207)

Решение

При свободных гармонических колебаниях пружинного маятника происходит непрерывное превращение энергии из одного вида в другой: из потенциальной в кинетическую и обратно. В идеальной системе без трения полная механическая энергия, являющаяся суммой потенциальной и кинетической энергий, остается постоянной.

Потенциальная энергия ($E_п$) пружинного маятника — это энергия упругой деформации пружины, которая зависит от смещения груза $\text{x}$ от положения равновесия и жесткости пружины $\text{k}$: $E_п = \frac{kx^2}{2}$. Эта энергия достигает своего максимального значения в точках максимального смещения (в крайних положениях, где $x = \pm A$, а $\text{A}$ — амплитуда), так как в этих точках деформация пружины наибольшая. В положении равновесия ($x = 0$) пружина не деформирована, и потенциальная энергия равна нулю.

Кинетическая энергия ($E_к$) маятника — это энергия движения его груза массой $\text{m}$ со скоростью $\text{v}$: $E_к = \frac{mv^2}{2}$. Эта энергия максимальна, когда маятник проходит положение равновесия ($x = 0$), так как в этой точке его скорость наибольшая. В крайних точках маятник на мгновение останавливается, его скорость становится равной нулю ($v = 0$), и кинетическая энергия в эти моменты также равна нулю.

Таким образом, процесс изменения энергий можно описать как непрерывный переход. В крайних точках вся энергия системы является потенциальной ($E = E_{п_{max}}$). По мере движения к положению равновесия потенциальная энергия уменьшается и преобразуется в кинетическую, которая возрастает. В положении равновесия вся энергия системы становится кинетической ($E = E_{к_{max}}$). Затем, при движении к другой крайней точке, кинетическая энергия снова преобразуется в потенциальную. Эти превращения происходят периодически и в противофазе: максимум одной энергии совпадает с минимумом (нулем) другой.

Математически, если координата маятника меняется по закону $x(t) = A \cos(\omega t)$, то зависимости энергий от времени выглядят так:$E_п(t) = \frac{kA^2}{2} \cos^2(\omega t)$ и $E_к(t) = \frac{kA^2}{2} \sin^2(\omega t)$.Их сумма, полная энергия $E = E_п + E_к = \frac{kA^2}{2}(\cos^2(\omega t) + \sin^2(\omega t)) = \frac{kA^2}{2}$, остается постоянной.

Ответ:

При свободных гармонических колебаниях пружинного маятника его потенциальная и кинетическая энергии периодически изменяются, переходя друг в друга. Потенциальная энергия максимальна в крайних точках траектории и равна нулю в положении равновесия. Кинетическая энергия, наоборот, максимальна в положении равновесия и равна нулю в крайних точках. Сумма потенциальной и кинетической энергий (полная механическая энергия) маятника остается постоянной.

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