Номер 2, страница 405 - гдз по физике 10 класс учебник Касьянов

Физика, 10 класс Учебник, автор: Касьянов Валерий Алексеевич, издательство Просвещение, Москва, 2021, белого цвета

Авторы: Касьянов В. А.

Тип: Учебник

Издательство: Просвещение

Год издания: 2021 - 2026

Уровень обучения: углублённый

Цвет обложки: белый самолет и молнии изображены

ISBN: 978-5-09-103621-3

Электростатика. 15. Энергия электромагнитного взаимодействия неподвижных зарядов. Параграф 87. Диэлектрики в электростатическом поле. Задачи - номер 2, страница 405.

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                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1129
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1130
                      #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:10 [
                            "id" => 6671
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik"
                          ]
                          #original: array:10 [
                            "id" => 6671
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1132
                      #items: array:1 [
                        0 => App\Models\Term {#1133
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "rossiya"
                          ]
                          #original: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "rossiya"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1134
                      #items: array:1 [
                        0 => App\Models\Term {#1135
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "moskva"
                          ]
                          #original: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "moskva"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1136
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1137
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1138
                      #items: array:1 [
                        0 => App\Models\Term {#1139
                          #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" => 39
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "углублённый"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "uglublennyy"
                          ]
                          #original: array:6 [
                            "id" => 39
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "углублённый"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "uglublennyy"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1140
                      #items: array:1 [
                        0 => App\Models\Term {#1141
                          #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" => "11"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1142
                      #items: array:1 [
                        0 => App\Models\Term {#1143
                          #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" => 33
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "stereotipnoe"
                          ]
                          #original: array:6 [
                            "id" => 33
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "stereotipnoe"
                          ]
                          #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 {#1144
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "самолет и молнии изображены"
                    "field_publication_year" => "2021"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "984"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_10/kasyanov-u/"
                    "field_isbn" => "978-5-09-103621-3"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_10/kasyanov-u/covers/cover1.webp?ts=1757588862"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_10/kasyanov-u/covers/cover1.webp?ts=1757588862"
                        "alt" => ""
                        "width" => "1604"
                        "height" => "2397"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1145
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1146
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1147
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/10-klass/fizika/kasyanov-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1148
                      #items: array:1 [
                        0 => App\Models\Term {#1149
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 45
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "белый"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "belyy"
                          ]
                          #original: array:6 [
                            "id" => 45
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "белый"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "belyy"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 381
                      "subject" => 556
                      "class_subject" => 494
                    ]
                  ]
                  #original: array:50 [
                    "id" => 7000
                    "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 {#1122}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1123}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1125}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1127}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1129}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1130}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1132}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1134}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1136}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1137}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1138}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1140}
                    "field_publication_number" => "11"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1142}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1144}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "самолет и молнии изображены"
                    "field_publication_year" => "2021"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "984"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_10/kasyanov-u/"
                    "field_isbn" => "978-5-09-103621-3"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_10/kasyanov-u/covers/cover1.webp?ts=1757588862"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_10/kasyanov-u/covers/cover1.webp?ts=1757588862"
                        "alt" => ""
                        "width" => "1604"
                        "height" => "2397"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1145}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1146}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1147}
                    "field_url" => "/10-klass/fizika/kasyanov-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1148}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 381
                      "subject" => 556
                      "class_subject" => 494
                    ]
                  ]
                  #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 {#1150
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1389608
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Электростатика"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1119}
            "field_page_start" => "362"
            "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 {#1152}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1150}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Branch {#1151
          #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" => 1389628
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "15. Энергия электромагнитного взаимодействия неподвижных зарядов"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1153
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "392"
            "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 {#1154
              #items: array:1 [
                0 => App\Models\Book {#1120}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1155
              #items: array:1 [
                0 => App\Models\Branch {#1034}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1389628
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "15. Энергия электромагнитного взаимодействия неподвижных зарядов"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1153}
            "field_page_start" => "392"
            "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 {#1154}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1155}
          ]
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          #dateFormat: null
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          #touches: []
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          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1156
          #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" => 1389636
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
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                0 => App\Models\Term {#1157
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
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                  #withCount: []
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                  #perPage: 15
                  +exists: true
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                  #attributes: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
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                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
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            "field_branch_covers" => []
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                0 => App\Models\Book {#1120}
              ]
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            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1168
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                0 => App\Models\Branch {#1167
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
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                    "id" => 1389628
                    "created_at" => "2026-04-10 13:58:26"
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                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1169 …2}
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                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1170 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1171 …2}
                  ]
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                    "id" => 1389628
                    "created_at" => "2026-04-10 13:58:26"
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                    "field_display_title" => "15. Энергия электромагнитного взаимодействия неподвижных зарядов"
                    "field_branch_order" => null
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                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1169 …2}
                    "field_page_start" => "392"
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                    "book" => Illuminate\Database\Eloquent\Collection {#1170 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1171 …2}
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
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          #original: array:24 [
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            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Диэлектрики в электростатическом поле"
            "field_branch_order" => "87"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1160}
            "field_page_start" => "402"
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1159}
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            0 => "*"
          ]
        }
        3 => App\Models\Branch {#1161
          #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" => 1389638
            "created_at" => "2026-04-10 13:58:26"
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            "field_display_title" => "Задачи"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1158
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "405"
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            "field_navigation_title" => null
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            "field_h1" => null
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1164
              #items: array:1 [
                0 => App\Models\Book {#1120}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1177
              #items: array:1 [
                0 => App\Models\Branch {#1176
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
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                    "created_at" => "2026-04-10 13:58:26"
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                    "field_branch_order" => "87"
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1178 …2}
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                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1179 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1180 …2}
                  ]
                  #original: array:24 [
                    "id" => 1389636
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Диэлектрики в электростатическом поле"
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                    0 => "*"
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            "id" => 1389638
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            "field_url" => null
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            0 => "*"
          ]
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      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1071
      #items: array:2 [
        0 => App\Models\Element {#1099
          #connection: "mysql"
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          #primaryKey: "id"
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          #attributes: array:7 [
            "id" => 1640790
            "created_at" => "2026-04-10 13:58:26"
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            "edition" => Illuminate\Database\Eloquent\Collection {#1089
              #items: array:1 [
                0 => App\Models\Edition {#1097
                  #connection: "mysql"
                  #table: "editions"
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                  #keyType: "int"
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                    "id" => 5810
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1095 …2}
                    "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"
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                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
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                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1093 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1094 …2}
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                    "id" => 5810
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              ]
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            }
            "task" => array:2 [
              "refs" => "1390482"
              "type" => "task"
            ]
            "text" => "<p><strong>2.</strong> Разность потенциалов между двумя заряженными плоскопараллельными пластинами в воздухе 200 В. После их погружения в жидкий аммиак разность потенциалов оказалась равной 8 В. Чему равна относительная диэлектрическая проницаемость аммиака?</p>"
            "img" => array:2 [
              0 => array:5 [
                "name" => "2-1.jpg"
                "alt" => null
                "width" => "1649"
                "height" => 185
                "path" => "/media/fizika_10/kasyanov-u/0-87zad/2-1.webp?ts=1757958190"
              ]
              1 => array:5 [
                "name" => "2-2.jpg"
                "alt" => null
                "width" => "1590"
                "height" => 185
                "path" => "/media/fizika_10/kasyanov-u/0-87zad/2-2.webp?ts=1757958190"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1640790
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1089}
            "task" => array:2 [
              "refs" => "1390482"
              "type" => "task"
            ]
            "text" => "<p><strong>2.</strong> Разность потенциалов между двумя заряженными плоскопараллельными пластинами в воздухе 200 В. После их погружения в жидкий аммиак разность потенциалов оказалась равной 8 В. Чему равна относительная диэлектрическая проницаемость аммиака?</p>"
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              1 => array:5 [
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                "alt" => null
                "width" => "1590"
                "height" => 185
                "path" => "/media/fizika_10/kasyanov-u/0-87zad/2-2.webp?ts=1757958190"
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            0 => "*"
          ]
        }
        1 => App\Models\Element {#1092
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 1693494
            "created_at" => "2026-04-10 13:58:26"
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            "edition" => Illuminate\Database\Eloquent\Collection {#1083
              #items: array:1 [
                0 => App\Models\Edition {#1091
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 6145
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1087 …2}
                    "field_content_type" => "free"
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                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1088 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1085 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1086 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
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            "text" => "<p><strong>Дано:</strong></p><p>Разность потенциалов в воздухе, $U_1 = 200 \text{ В}$<br>Разность потенциалов в жидком аммиаке, $U_2 = 8 \text{ В}$<br>Относительная диэлектрическая проницаемость воздуха, $\epsilon_1 \approx 1$</p><p>Все данные представлены в системе СИ.</p><p><strong>Найти:</strong></p><p>Относительную диэлектрическую проницаемость аммиака, $\epsilon_2$.</p><p><strong>Решение:</strong></p><p>Разность потенциалов $U$ между двумя плоскопараллельными пластинами связана с напряженностью электрического поля $E$ и расстоянием между пластинами $d$ соотношением:</p><p>$U = E \cdot d$</p><p>Напряженность электрического поля между пластинами зависит от поверхностной плотности заряда на пластинах $\sigma$ и диэлектрической проницаемости среды $\epsilon$:</p><p>$E = \frac{\sigma}{\epsilon_0 \epsilon}$</p><p>где $\epsilon_0$ — электрическая постоянная, а $\epsilon$ — относительная диэлектрическая проницаемость среды.</p><p>Подставив выражение для напряженности в формулу для разности потенциалов, получим:</p><p>$U = \frac{\sigma d}{\epsilon_0 \epsilon}$</p><p>Запишем это уравнение для двух случаев: когда пластины находятся в воздухе и когда они погружены в жидкий аммиак. При погружении в аммиак заряд на пластинах $q$ (и, следовательно, поверхностная плотность заряда $\sigma$) и расстояние между ними $d$ не изменяются.</p><p><strong>1.</strong> Для воздуха ($\epsilon_1 \approx 1$):</p><p>$U_1 = \frac{\sigma d}{\epsilon_0 \epsilon_1}$</p><p><strong>2.</strong> Для жидкого аммиака (с неизвестной проницаемостью $\epsilon_2$):</p><p>$U_2 = \frac{\sigma d}{\epsilon_0 \epsilon_2}$</p><p>Теперь разделим первое уравнение на второе, чтобы найти соотношение между разностями потенциалов и диэлектрическими проницаемостями:</p><p>$\frac{U_1}{U_2} = \frac{\frac{\sigma d}{\epsilon_0 \epsilon_1}}{\frac{\sigma d}{\epsilon_0 \epsilon_2}} = \frac{\epsilon_2}{\epsilon_1}$</p><p>Отсюда можно выразить искомую величину $\epsilon_2$:</p><p>$\epsilon_2 = \epsilon_1 \cdot \frac{U_1}{U_2}$</p><p>Так как диэлектрическая проницаемость воздуха $\epsilon_1$ очень близка к 1, можно принять $\epsilon_1 = 1$. Тогда формула упрощается:</p><p>$\epsilon_2 = \frac{U_1}{U_2}$</p><p>Подставим числовые значения из условия задачи:</p><p>$\epsilon_2 = \frac{200 \text{ В}}{8 \text{ В}} = 25$</p><p><strong>Ответ:</strong> относительная диэлектрическая проницаемость аммиака равна 25.</p>"
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            "text" => "<p><strong>Дано:</strong></p><p>Разность потенциалов в воздухе, $U_1 = 200 \text{ В}$<br>Разность потенциалов в жидком аммиаке, $U_2 = 8 \text{ В}$<br>Относительная диэлектрическая проницаемость воздуха, $\epsilon_1 \approx 1$</p><p>Все данные представлены в системе СИ.</p><p><strong>Найти:</strong></p><p>Относительную диэлектрическую проницаемость аммиака, $\epsilon_2$.</p><p><strong>Решение:</strong></p><p>Разность потенциалов $U$ между двумя плоскопараллельными пластинами связана с напряженностью электрического поля $E$ и расстоянием между пластинами $d$ соотношением:</p><p>$U = E \cdot d$</p><p>Напряженность электрического поля между пластинами зависит от поверхностной плотности заряда на пластинах $\sigma$ и диэлектрической проницаемости среды $\epsilon$:</p><p>$E = \frac{\sigma}{\epsilon_0 \epsilon}$</p><p>где $\epsilon_0$ — электрическая постоянная, а $\epsilon$ — относительная диэлектрическая проницаемость среды.</p><p>Подставив выражение для напряженности в формулу для разности потенциалов, получим:</p><p>$U = \frac{\sigma d}{\epsilon_0 \epsilon}$</p><p>Запишем это уравнение для двух случаев: когда пластины находятся в воздухе и когда они погружены в жидкий аммиак. При погружении в аммиак заряд на пластинах $q$ (и, следовательно, поверхностная плотность заряда $\sigma$) и расстояние между ними $d$ не изменяются.</p><p><strong>1.</strong> Для воздуха ($\epsilon_1 \approx 1$):</p><p>$U_1 = \frac{\sigma d}{\epsilon_0 \epsilon_1}$</p><p><strong>2.</strong> Для жидкого аммиака (с неизвестной проницаемостью $\epsilon_2$):</p><p>$U_2 = \frac{\sigma d}{\epsilon_0 \epsilon_2}$</p><p>Теперь разделим первое уравнение на второе, чтобы найти соотношение между разностями потенциалов и диэлектрическими проницаемостями:</p><p>$\frac{U_1}{U_2} = \frac{\frac{\sigma d}{\epsilon_0 \epsilon_1}}{\frac{\sigma d}{\epsilon_0 \epsilon_2}} = \frac{\epsilon_2}{\epsilon_1}$</p><p>Отсюда можно выразить искомую величину $\epsilon_2$:</p><p>$\epsilon_2 = \epsilon_1 \cdot \frac{U_1}{U_2}$</p><p>Так как диэлектрическая проницаемость воздуха $\epsilon_1$ очень близка к 1, можно принять $\epsilon_1 = 1$. Тогда формула упрощается:</p><p>$\epsilon_2 = \frac{U_1}{U_2}$</p><p>Подставим числовые значения из условия задачи:</p><p>$\epsilon_2 = \frac{200 \text{ В}}{8 \text{ В}} = 25$</p><p><strong>Ответ:</strong> относительная диэлектрическая проницаемость аммиака равна 25.</p>"
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№2 (с. 405)
Условие. №2 (с. 405)
скриншот условия
Физика, 10 класс Учебник, автор: Касьянов Валерий Алексеевич, издательство Просвещение, Москва, 2021, белого цвета, страница 405, номер 2, Условие
Физика, 10 класс Учебник, автор: Касьянов Валерий Алексеевич, издательство Просвещение, Москва, 2021, белого цвета, страница 405, номер 2, Условие (продолжение 2)

2. Разность потенциалов между двумя заряженными плоскопараллельными пластинами в воздухе 200 В. После их погружения в жидкий аммиак разность потенциалов оказалась равной 8 В. Чему равна относительная диэлектрическая проницаемость аммиака?

Решение. №2 (с. 405)

Дано:

Разность потенциалов в воздухе, $U_1 = 200 \text{ В}$
Разность потенциалов в жидком аммиаке, $U_2 = 8 \text{ В}$
Относительная диэлектрическая проницаемость воздуха, $\epsilon_1 \approx 1$

Все данные представлены в системе СИ.

Найти:

Относительную диэлектрическую проницаемость аммиака, $\epsilon_2$.

Решение:

Разность потенциалов $U$ между двумя плоскопараллельными пластинами связана с напряженностью электрического поля $E$ и расстоянием между пластинами $d$ соотношением:

$U = E \cdot d$

Напряженность электрического поля между пластинами зависит от поверхностной плотности заряда на пластинах $\sigma$ и диэлектрической проницаемости среды $\epsilon$:

$E = \frac{\sigma}{\epsilon_0 \epsilon}$

где $\epsilon_0$ — электрическая постоянная, а $\epsilon$ — относительная диэлектрическая проницаемость среды.

Подставив выражение для напряженности в формулу для разности потенциалов, получим:

$U = \frac{\sigma d}{\epsilon_0 \epsilon}$

Запишем это уравнение для двух случаев: когда пластины находятся в воздухе и когда они погружены в жидкий аммиак. При погружении в аммиак заряд на пластинах $q$ (и, следовательно, поверхностная плотность заряда $\sigma$) и расстояние между ними $d$ не изменяются.

1. Для воздуха ($\epsilon_1 \approx 1$):

$U_1 = \frac{\sigma d}{\epsilon_0 \epsilon_1}$

2. Для жидкого аммиака (с неизвестной проницаемостью $\epsilon_2$):

$U_2 = \frac{\sigma d}{\epsilon_0 \epsilon_2}$

Теперь разделим первое уравнение на второе, чтобы найти соотношение между разностями потенциалов и диэлектрическими проницаемостями:

$\frac{U_1}{U_2} = \frac{\frac{\sigma d}{\epsilon_0 \epsilon_1}}{\frac{\sigma d}{\epsilon_0 \epsilon_2}} = \frac{\epsilon_2}{\epsilon_1}$

Отсюда можно выразить искомую величину $\epsilon_2$:

$\epsilon_2 = \epsilon_1 \cdot \frac{U_1}{U_2}$

Так как диэлектрическая проницаемость воздуха $\epsilon_1$ очень близка к 1, можно принять $\epsilon_1 = 1$. Тогда формула упрощается:

$\epsilon_2 = \frac{U_1}{U_2}$

Подставим числовые значения из условия задачи:

$\epsilon_2 = \frac{200 \text{ В}}{8 \text{ В}} = 25$

Ответ: относительная диэлектрическая проницаемость аммиака равна 25.

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