Номер 2, страница 41, часть 3 - гдз по физике 9 класс рабочая тетрадь Грачев, Погожев

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

Тип: рабочая тетрадь

Издательство: Просвещение

Год издания: 2021 - 2026

Часть: 3

Цвет обложки: синий

ISBN: 978-5-09-098826-1 (ч.1) 978-5-09-098880-3 (ч.2) 978-5-09-098881-0 (ч.3)

Часть 3. Глава 8. Оптика. Параграф 47. Тонкие линзы - номер 2, страница 41.

App\Models\Task {#1030 // resources/views/models/task/default.blade.php
  #connection: "mysql"
  #table: "tasks"
  #primaryKey: "id"
  #keyType: "int"
  +incrementing: true
  #with: []
  #withCount: []
  +preventsLazyLoading: false
  #perPage: 15
  +exists: true
  +wasRecentlyCreated: false
  #escapeWhenCastingToString: false
  #attributes: array:24 [
    "id" => 1435288
    "created_at" => "2026-04-10 13:58:26"
    "updated_at" => null
    "field_page_start" => "41"
    "field_page_end" => null
    "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad/47-2"
    "field_display_title" => "2"
    "field_outside_task" => null
    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1037
      #items: array:1 [
        0 => App\Models\Term {#1036
          #connection: "mysql"
          #table: "terms"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: false
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
          #original: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
          #changes: []
          #casts: []
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          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "field_metatags_title" => null
    "field_metatags_description" => null
    "field_h1" => null
    "field_description_top" => null
    "field_description_bottom" => null
    "field_match" => null
    "breadcrumbs" => []
    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1035
      #items: []
      #escapeWhenCastingToString: false
    }
    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1046
      #items: array:1 [
        0 => App\Models\Branch {#1045
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1434847
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => null
            "field_branch_order" => "3"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1050
              #items: array:1 [
                0 => App\Models\Term {#1047
                  #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" => 31
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Часть"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Часть"
                      "field_creative_case" => "Частью"
                      "field_dative_case" => "Части"
                      "field_genitive_case" => "Части"
                      "field_nominative_case" => "Часть"
                      "field_prepositional_case" => "Части"
                    ]
                    "field_page_check_not_needed" => "1"
                    "field_short_name" => "ч."
                  ]
                  #original: array:7 [
                    "id" => 31
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Часть"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Часть"
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                      "field_genitive_case" => "Части"
                      "field_nominative_case" => "Часть"
                      "field_prepositional_case" => "Части"
                    ]
                    "field_page_check_not_needed" => "1"
                    "field_short_name" => "ч."
                  ]
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                  #dateFormat: null
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                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
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            "field_display_task_interval" => "0"
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            "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 {#1058
              #items: array:1 [
                0 => App\Models\Book {#1057
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:50 [
                    "id" => 1203
                    "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 {#1062
                      #items: array:1 [
                        0 => App\Models\Term {#1059
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [
                            "id" => 6493
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Физика"
                            "field_abbreviated_name" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "физику"
                              "field_creative_case" => "физикой"
                              "field_dative_case" => "физике"
                              "field_genitive_case" => "физики"
                              "field_nominative_case" => "физика"
                              "field_prepositional_case" => "физике"
                            ]
                            "field_foreign_lang_name" => null
                            "field_short_name" => null
                            "field_subject_type" => "technical_subject"
                            "field_translit" => "fizika"
                          ]
                          #original: array:10 [
                            "id" => 6493
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Физика"
                            "field_abbreviated_name" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "физику"
                              "field_creative_case" => "физикой"
                              "field_dative_case" => "физике"
                              "field_genitive_case" => "физики"
                              "field_nominative_case" => "физика"
                              "field_prepositional_case" => "физике"
                            ]
                            "field_foreign_lang_name" => null
                            "field_short_name" => null
                            "field_subject_type" => "technical_subject"
                            "field_translit" => "fizika"
                          ]
                          #changes: []
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                          #attributeCastCache: []
                          #dateFormat: null
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                          #visible: []
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                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1064
                      #items: array:1 [
                        0 => App\Models\Term {#1061
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
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                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 5458
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "9"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "девятый"
                              "field_creative_case" => "девятым"
                              "field_dative_case" => "девятому"
                              "field_genitive_case" => "девятого"
                              "field_nominative_case" => "девятый"
                              "field_prepositional_case" => "девятом"
                            ]
                            "field_translit" => "devjatyj"
                          ]
                          #original: array:6 [
                            "id" => 5458
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "9"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "девятый"
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                              "field_genitive_case" => "девятого"
                              "field_nominative_case" => "девятый"
                              "field_prepositional_case" => "девятом"
                            ]
                            "field_translit" => "devjatyj"
                          ]
                          #changes: []
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                          #dateFormat: null
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                      ]
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                    }
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1066
                      #items: array:1 [
                        0 => App\Models\Term {#1063
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
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                          #attributes: array:6 [
                            "id" => 5153
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_cases" => null
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                          ]
                          #original: array:6 [
                            "id" => 5153
                            "created_at" => "2026-04-10 13:58:26"
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                          ]
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                    "field_author" => Illuminate\Database\Eloquent\Collection {#1060
                      #items: array:4 [
                        0 => App\Models\Term {#1079
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                            "field_foreign_lang_patronymic" => null
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                            "field_name" => "Александр"
                            "field_patronymic" => "Васильевич"
                            "field_surname_rp" => null
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                          #original: array:12 [
                            "id" => 4180
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_foreign_lang_patronymic" => null
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                            "field_name" => "Александр"
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                          ]
                          #changes: []
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                        1 => App\Models\Term {#1080
                          #connection: "mysql"
                          #table: "terms"
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                            "created_at" => "2026-04-10 13:58:26"
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                            "field_name" => "Владимир"
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                          #original: array:12 [
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Погожев"
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                            "field_degree_rp" => null
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                            "field_foreign_lang_patronymic" => null
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                            "field_name" => "Владимир"
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                        2 => App\Models\Term {#1077
                          #connection: "mysql"
                          #table: "terms"
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                            "created_at" => "2026-04-10 13:58:26"
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                        3 => App\Models\Term {#1078
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                          #attributes: array:12 [
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Екатерина"
                            "field_patronymic" => "Анатольевна"
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                            "id" => 4007
                            "created_at" => "2026-04-10 13:58:26"
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                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1075
                      #items: []
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                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1072
                      #items: array:1 [
                        0 => App\Models\Term {#1067
                          #connection: "mysql"
                          #table: "terms"
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                          #with: []
                          #withCount: []
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                          #perPage: 15
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                          #attributes: array:10 [
                            "id" => 6736
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                              "field_genitive_case" => "рабочей тетради"
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                              "field_prepositional_case" => "рабочей тетради"
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                            "field_short_name_foreign" => null
                            "field_translit" => "rabochaya tetrad"
                          ]
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "рабочая тетрадь"
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                            "field_cases" => array:6 [
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                              "field_genitive_case" => "рабочей тетради"
                              "field_nominative_case" => "рабочая тетрадь"
                              "field_prepositional_case" => "рабочей тетради"
                            ]
                            "field_plural_form" => "рабочие тетради"
                            "field_short_name" => "рт"
                            "field_short_name_foreign" => null
                            "field_translit" => "rabochaya tetrad"
                          ]
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                          #dateFormat: null
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                      ]
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                    "field_country" => Illuminate\Database\Eloquent\Collection {#1070
                      #items: array:1 [
                        0 => App\Models\Term {#1073
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
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                          #attributes: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
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                            ]
                            "field_translit" => "rossiya"
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                            "created_at" => "2026-04-10 13:58:26"
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                      ]
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                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1071
                      #items: array:1 [
                        0 => App\Models\Term {#1074
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
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                          #withCount: []
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                          #attributes: array:6 [
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                              "field_nominative_case" => null
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                            ]
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                          ]
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
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                      ]
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                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1068
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                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1065
                      #items: []
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                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1069
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1084
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                        0 => App\Models\Term {#1081
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
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                          #withCount: []
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                            "created_at" => "2026-04-10 13:58:26"
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                          ]
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                        0 => App\Models\Term {#1083
                          #connection: "mysql"
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                            ]
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                            "created_at" => "2026-04-10 13:58:26"
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                          #dateFormat: null
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                      ]
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                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1085
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2021"
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                    "field_part" => "1, 2, 3"
                    "field_part_writing" => "Часть"
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "594"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/grachev-rt/"
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                    "field_cover" => array:3 [
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                      2 => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                    ]
                    "field_cover_alts" => array:3 [
                      0 => ""
                      1 => ""
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                      ]
                      1 => array:4 [
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                      ]
                      2 => array:4 [
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                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1082
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1087
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1088
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1092
                      #items: array:1 [
                        0 => App\Models\Term {#1089
                          #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
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                            ]
                            "field_translit" => "siniy"
                          ]
                          #original: array:6 [
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
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                    ]
                  ]
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                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1062}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1064}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1066}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1060}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1075}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1072}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1070}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1071}
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                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1065}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1069}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1084}
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                    "field_part" => "1, 2, 3"
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                    "field_cover" => array:3 [
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                      2 => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                    ]
                    "field_cover_alts" => array:3 [
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                      1 => ""
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                      ]
                      1 => array:4 [
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                      ]
                      2 => array:4 [
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                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1087}
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                    "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1092}
                    "field_metatags_title" => null
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                    0 => "*"
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                }
              ]
              #escapeWhenCastingToString: false
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            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1048
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            }
          ]
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            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1050}
            "field_page_start" => "3"
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            "field_h1" => null
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            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1058}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1048}
          ]
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          #dateFormat: null
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        }
      ]
      #escapeWhenCastingToString: false
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    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1116
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        0 => App\Models\Branch {#1126
          #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" => 1434847
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => null
            "field_branch_order" => "3"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1127
              #items: array:1 [
                0 => App\Models\Term {#1047}
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "3"
            "field_branch_display" => "0"
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            "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 {#1128
              #items: array:1 [
                0 => App\Models\Book {#1057}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1129
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1434847
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => null
            "field_branch_order" => "3"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1127}
            "field_page_start" => "3"
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            0 => "*"
          ]
        }
        1 => App\Models\Branch {#1130
          #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" => 1434852
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Оптика"
            "field_branch_order" => "8"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1134
              #items: array:1 [
                0 => App\Models\Term {#1131
                  #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" => 29
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Глава"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Главу"
                      "field_creative_case" => "Главой"
                      "field_dative_case" => "Главе"
                      "field_genitive_case" => "Главы"
                      "field_nominative_case" => "Глава"
                      "field_prepositional_case" => "Главе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => null
                  ]
                  #original: array:7 [
                    "id" => 29
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Глава"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Главу"
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                      "field_genitive_case" => "Главы"
                      "field_nominative_case" => "Глава"
                      "field_prepositional_case" => "Главе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => null
                  ]
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                  #attributeCastCache: []
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                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "15"
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            "field_display_branch_in_title" => "1"
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            "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 {#1133
              #items: array:1 [
                0 => App\Models\Book {#1057}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1132
              #items: array:1 [
                0 => App\Models\Branch {#1045}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1434852
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            "updated_at" => null
            "field_display_title" => "Оптика"
            "field_branch_order" => "8"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1134}
            "field_page_start" => "15"
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            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1133}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1132}
          ]
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            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1135
          #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" => 1434861
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Тонкие линзы"
            "field_branch_order" => "47"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1139
              #items: array:1 [
                0 => App\Models\Term {#1136
                  #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"
                      "field_prepositional_case" => "Параграфе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
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                  #visible: []
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "40"
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            "field_navigation_title" => null
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            "field_metatags_description" => null
            "field_h1" => null
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            "field_description_bottom" => null
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            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1138
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                0 => App\Models\Book {#1057}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1147
              #items: array:1 [
                0 => App\Models\Branch {#1146
                  #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 [
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                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1148
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                      #escapeWhenCastingToString: false
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                    "book" => Illuminate\Database\Eloquent\Collection {#1149
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                      ]
                      #escapeWhenCastingToString: false
                    }
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1150
                      #items: array:1 [
                        0 => App\Models\Branch {#1045}
                      ]
                      #escapeWhenCastingToString: false
                    }
                  ]
                  #original: array:24 [
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                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1148}
                    "field_page_start" => "15"
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                    "field_navigation_title" => null
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                    "book" => Illuminate\Database\Eloquent\Collection {#1149}
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
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          #original: array:24 [
            "id" => 1434861
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Тонкие линзы"
            "field_branch_order" => "47"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1139}
            "field_page_start" => "40"
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            "book" => Illuminate\Database\Eloquent\Collection {#1138}
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          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1038
      #items: array:2 [
        0 => App\Models\Element {#1108
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:7 [
            "id" => 1698676
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1100
              #items: array:1 [
                0 => App\Models\Edition {#1106
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
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                  #attributes: array:21 [
                    "id" => 6173
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1104
                      #items: array:1 [
                        0 => App\Models\Term {#1107
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
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                          #escapeWhenCastingToString: false
                          #attributes: array:6 [ …6]
                          #original: array:6 [ …6]
                          #changes: []
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                          #hidden: []
                          #visible: []
                          #fillable: []
                           …1
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "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 {#1105
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1103
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1102
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6173
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1104}
                    "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 {#1105}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1103}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1102}
                    "field_content_source" => null
                  ]
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1435288"
              "type" => "task"
            ]
            "text" => "<p><strong>2.</strong> На рис. 41 показаны главные плоскости и главные оптические оси двух тонких линз, находящихся в воздухе, а также ход в них пучков синего света. Определите, какая из этих линз является собирающей, а какая – рассеивающей. Отметьте на каждом из рисунков положение фокальной плоскости. Используя линейку и указанный на рисунке масштаб, определите оптические силы этих линз.</p><p><strong>а</strong></p><p>$A_1$</p><p>$C_1$</p><p>$D_1$</p><p>$B_1$</p><p>5 см</p><p><strong>б</strong></p><p>$A_2$</p><p>$C_2$</p><p>$D_2$</p><p>$B_2$</p><p>Рис. 41</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "2-1.jpg"
                "alt" => null
                "width" => "1953"
                "height" => 845
                "path" => "/media/fizika_09/grachev-rt/0-47/2-1.webp?ts=1759402865"
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            "edition" => Illuminate\Database\Eloquent\Collection {#1100}
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            "text" => "<p><strong>2.</strong> На рис. 41 показаны главные плоскости и главные оптические оси двух тонких линз, находящихся в воздухе, а также ход в них пучков синего света. Определите, какая из этих линз является собирающей, а какая – рассеивающей. Отметьте на каждом из рисунков положение фокальной плоскости. Используя линейку и указанный на рисунке масштаб, определите оптические силы этих линз.</p><p><strong>а</strong></p><p>$A_1$</p><p>$C_1$</p><p>$D_1$</p><p>$B_1$</p><p>5 см</p><p><strong>б</strong></p><p>$A_2$</p><p>$C_2$</p><p>$D_2$</p><p>$B_2$</p><p>Рис. 41</p>"
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            "text" => "<p><strong>Дано:</strong></p> <p>Масштабный отрезок, указанный на рисунке, соответствует расстоянию $L = 5 \text{ см}$.</p> <p>Перевод в систему СИ:</p> <p>$L = 0.05 \text{ м}$</p> <p><strong>Найти:</strong></p> <p>1. Какая из линз является собирающей, а какая — рассеивающей.</p> <p>2. Положение фокальной плоскости для каждой линзы.</p> <p>3. Оптические силы линз $D_a$ и $D_b$.</p> <p><strong>Решение:</strong></p> <p>Оптическая сила линзы $D$ — это физическая величина, обратная её фокусному расстоянию $F$, выраженному в метрах. Формула для расчёта оптической силы: $D = \frac{1}{F}$.</p> <p>Фокусное расстояние — это расстояние от главной оптической плоскости линзы до её главного фокуса. Главный фокус — это точка на главной оптической оси, в которой собираются лучи (для собирающей линзы) или их продолжения (для рассеивающей линзы), падающие на линзу параллельно этой оси.</p> <p><strong>a</strong></p> <p>На рисунке `а` показано, что пучок параллельных лучей света после прохождения через линзу сходится (собирается) в одной точке, расположенной на главной оптической оси. Следовательно, эта линза является <strong>собирающей</strong>.</p> <p>Фокальная плоскость — это плоскость, перпендикулярная главной оптической оси и проходящая через главный фокус. На рисунке `а` фокальная плоскость проходит через точку схождения лучей, расположенную справа от линзы.</p> <p>Измерим фокусное расстояние $F_a$, используя масштаб. Расстояние от главной плоскости линзы $A_1B_1$ до точки фокуса на рисунке равно длине масштабного отрезка. Таким образом, фокусное расстояние линзы $F_a = 5 \text{ см} = 0.05 \text{ м}$. Для собирающей линзы фокусное расстояние считается положительным.</p> <p>Рассчитаем оптическую силу линзы:</p> <p>$D_a = \frac{1}{F_a} = \frac{1}{0.05 \text{ м}} = 20 \text{ дптр}$.</p> <p><strong>Ответ:</strong> Линза `а` является собирающей. Фокальная плоскость расположена справа от линзы в месте схождения лучей. Оптическая сила линзы составляет $20 \text{ дптр}$.</p> <p><strong>б</strong></p> <p>На рисунке `б` показано, что пучок параллельных лучей света после прохождения через линзу становится расходящимся. Следовательно, эта линза является <strong>рассеивающей</strong>.</p> <p>У рассеивающей линзы фокус мнимый. Он находится в точке, где пересекаются продолжения расходящихся лучей, построенные в обратном направлении. На рисунке `б` фокальная плоскость проходит через мнимый фокус, расположенный слева от линзы.</p> <p>Определим фокусное расстояние $F_b$. Для этого необходимо мысленно продолжить расходящиеся лучи в обратную сторону до их пересечения с главной оптической осью. Из рисунка видно, что расстояние от главной плоскости линзы $A_2B_2$ до этой точки (мнимого фокуса) также равно длине масштабного отрезка. Таким образом, модуль фокусного расстояния $|F_b| = 5 \text{ см} = 0.05 \text{ м}$. По правилу знаков, фокусное расстояние рассеивающей линзы считается отрицательным, поэтому $F_b = -0.05 \text{ м}$.</p> <p>Рассчитаем оптическую силу линзы:</p> <p>$D_b = \frac{1}{F_b} = \frac{1}{-0.05 \text{ м}} = -20 \text{ дптр}$.</p> <p><strong>Ответ:</strong> Линза `б` является рассеивающей. Фокальная плоскость расположена слева от линзы в точке, где пересекаются продолжения расходящихся лучей. Оптическая сила линзы составляет $-20 \text{ дптр}$.</p>"
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            "text" => "<p><strong>Дано:</strong></p> <p>Масштабный отрезок, указанный на рисунке, соответствует расстоянию $L = 5 \text{ см}$.</p> <p>Перевод в систему СИ:</p> <p>$L = 0.05 \text{ м}$</p> <p><strong>Найти:</strong></p> <p>1. Какая из линз является собирающей, а какая — рассеивающей.</p> <p>2. Положение фокальной плоскости для каждой линзы.</p> <p>3. Оптические силы линз $D_a$ и $D_b$.</p> <p><strong>Решение:</strong></p> <p>Оптическая сила линзы $D$ — это физическая величина, обратная её фокусному расстоянию $F$, выраженному в метрах. Формула для расчёта оптической силы: $D = \frac{1}{F}$.</p> <p>Фокусное расстояние — это расстояние от главной оптической плоскости линзы до её главного фокуса. Главный фокус — это точка на главной оптической оси, в которой собираются лучи (для собирающей линзы) или их продолжения (для рассеивающей линзы), падающие на линзу параллельно этой оси.</p> <p><strong>a</strong></p> <p>На рисунке `а` показано, что пучок параллельных лучей света после прохождения через линзу сходится (собирается) в одной точке, расположенной на главной оптической оси. Следовательно, эта линза является <strong>собирающей</strong>.</p> <p>Фокальная плоскость — это плоскость, перпендикулярная главной оптической оси и проходящая через главный фокус. На рисунке `а` фокальная плоскость проходит через точку схождения лучей, расположенную справа от линзы.</p> <p>Измерим фокусное расстояние $F_a$, используя масштаб. Расстояние от главной плоскости линзы $A_1B_1$ до точки фокуса на рисунке равно длине масштабного отрезка. Таким образом, фокусное расстояние линзы $F_a = 5 \text{ см} = 0.05 \text{ м}$. Для собирающей линзы фокусное расстояние считается положительным.</p> <p>Рассчитаем оптическую силу линзы:</p> <p>$D_a = \frac{1}{F_a} = \frac{1}{0.05 \text{ м}} = 20 \text{ дптр}$.</p> <p><strong>Ответ:</strong> Линза `а` является собирающей. Фокальная плоскость расположена справа от линзы в месте схождения лучей. Оптическая сила линзы составляет $20 \text{ дптр}$.</p> <p><strong>б</strong></p> <p>На рисунке `б` показано, что пучок параллельных лучей света после прохождения через линзу становится расходящимся. Следовательно, эта линза является <strong>рассеивающей</strong>.</p> <p>У рассеивающей линзы фокус мнимый. Он находится в точке, где пересекаются продолжения расходящихся лучей, построенные в обратном направлении. На рисунке `б` фокальная плоскость проходит через мнимый фокус, расположенный слева от линзы.</p> <p>Определим фокусное расстояние $F_b$. Для этого необходимо мысленно продолжить расходящиеся лучи в обратную сторону до их пересечения с главной оптической осью. Из рисунка видно, что расстояние от главной плоскости линзы $A_2B_2$ до этой точки (мнимого фокуса) также равно длине масштабного отрезка. Таким образом, модуль фокусного расстояния $|F_b| = 5 \text{ см} = 0.05 \text{ м}$. По правилу знаков, фокусное расстояние рассеивающей линзы считается отрицательным, поэтому $F_b = -0.05 \text{ м}$.</p> <p>Рассчитаем оптическую силу линзы:</p> <p>$D_b = \frac{1}{F_b} = \frac{1}{-0.05 \text{ м}} = -20 \text{ дптр}$.</p> <p><strong>Ответ:</strong> Линза `б` является рассеивающей. Фокальная плоскость расположена слева от линзы в точке, где пересекаются продолжения расходящихся лучей. Оптическая сила линзы составляет $-20 \text{ дптр}$.</p>"
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№2 (с. 41)
Условие. №2 (с. 41)
скриншот условия
Физика, 9 класс рабочая тетрадь, авторы: Грачев Александр Васильевич, Погожев Владимир Александрович, Боков Павел Юрьевич, Вишнякова Екатерина Анатольевна, издательство Просвещение, Москва, 2021, Часть 3, страница 41, номер 2, Условие

2. На рис. 41 показаны главные плоскости и главные оптические оси двух тонких линз, находящихся в воздухе, а также ход в них пучков синего света. Определите, какая из этих линз является собирающей, а какая – рассеивающей. Отметьте на каждом из рисунков положение фокальной плоскости. Используя линейку и указанный на рисунке масштаб, определите оптические силы этих линз.

а

$A_1$

$C_1$

$D_1$

$B_1$

5 см

б

$A_2$

$C_2$

$D_2$

$B_2$

Рис. 41

Решение. №2 (с. 41)

Дано:

Масштабный отрезок, указанный на рисунке, соответствует расстоянию $L = 5 \text{ см}$.

Перевод в систему СИ:

$L = 0.05 \text{ м}$

Найти:

1. Какая из линз является собирающей, а какая — рассеивающей.

2. Положение фокальной плоскости для каждой линзы.

3. Оптические силы линз $D_a$ и $D_b$.

Решение:

Оптическая сила линзы $D$ — это физическая величина, обратная её фокусному расстоянию $F$, выраженному в метрах. Формула для расчёта оптической силы: $D = \frac{1}{F}$.

Фокусное расстояние — это расстояние от главной оптической плоскости линзы до её главного фокуса. Главный фокус — это точка на главной оптической оси, в которой собираются лучи (для собирающей линзы) или их продолжения (для рассеивающей линзы), падающие на линзу параллельно этой оси.

a

На рисунке `а` показано, что пучок параллельных лучей света после прохождения через линзу сходится (собирается) в одной точке, расположенной на главной оптической оси. Следовательно, эта линза является собирающей.

Фокальная плоскость — это плоскость, перпендикулярная главной оптической оси и проходящая через главный фокус. На рисунке `а` фокальная плоскость проходит через точку схождения лучей, расположенную справа от линзы.

Измерим фокусное расстояние $F_a$, используя масштаб. Расстояние от главной плоскости линзы $A_1B_1$ до точки фокуса на рисунке равно длине масштабного отрезка. Таким образом, фокусное расстояние линзы $F_a = 5 \text{ см} = 0.05 \text{ м}$. Для собирающей линзы фокусное расстояние считается положительным.

Рассчитаем оптическую силу линзы:

$D_a = \frac{1}{F_a} = \frac{1}{0.05 \text{ м}} = 20 \text{ дптр}$.

Ответ: Линза `а` является собирающей. Фокальная плоскость расположена справа от линзы в месте схождения лучей. Оптическая сила линзы составляет $20 \text{ дптр}$.

б

На рисунке `б` показано, что пучок параллельных лучей света после прохождения через линзу становится расходящимся. Следовательно, эта линза является рассеивающей.

У рассеивающей линзы фокус мнимый. Он находится в точке, где пересекаются продолжения расходящихся лучей, построенные в обратном направлении. На рисунке `б` фокальная плоскость проходит через мнимый фокус, расположенный слева от линзы.

Определим фокусное расстояние $F_b$. Для этого необходимо мысленно продолжить расходящиеся лучи в обратную сторону до их пересечения с главной оптической осью. Из рисунка видно, что расстояние от главной плоскости линзы $A_2B_2$ до этой точки (мнимого фокуса) также равно длине масштабного отрезка. Таким образом, модуль фокусного расстояния $|F_b| = 5 \text{ см} = 0.05 \text{ м}$. По правилу знаков, фокусное расстояние рассеивающей линзы считается отрицательным, поэтому $F_b = -0.05 \text{ м}$.

Рассчитаем оптическую силу линзы:

$D_b = \frac{1}{F_b} = \frac{1}{-0.05 \text{ м}} = -20 \text{ дптр}$.

Ответ: Линза `б` является рассеивающей. Фокальная плоскость расположена слева от линзы в точке, где пересекаются продолжения расходящихся лучей. Оптическая сила линзы составляет $-20 \text{ дптр}$.

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