Номер 3, страница 373 - 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. 14. Силы электромагнитного взаимодействия неподвижных зарядов. Параграф 79. Закон Кулона. Задачи - номер 3, страница 373.

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 [
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    "field_page_start" => "373"
    "field_page_end" => null
    "field_url" => "/10-klass/fizika/kasyanov-uchebnik/79zad-3"
    "field_display_title" => "3"
    "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
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          #attributes: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
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              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
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            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
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              "field_prepositional_case" => "номере"
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    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1073
      #items: array:1 [
        0 => App\Models\Branch {#1034
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
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            "book" => Illuminate\Database\Eloquent\Collection {#1038
              #items: array:1 [
                0 => App\Models\Book {#1040
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
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                      #escapeWhenCastingToString: false
                    }
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                      #escapeWhenCastingToString: false
                    }
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                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1064
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                    "field_under_the_edition_degree" => null
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                    "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"
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                    ]
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                      0 => ""
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                    "field_covers" => array:1 [
                      0 => array:4 [ …4]
                    ]
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                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1066
                      #items: []
                      #escapeWhenCastingToString: false
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                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/10-klass/fizika/kasyanov-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1068
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                      #escapeWhenCastingToString: false
                    }
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                  #original: array:50 [
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                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1041}
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                    "field_series" => Illuminate\Database\Eloquent\Collection {#1056}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1057}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1058}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1060}
                    "field_publication_number" => "11"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1062}
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                    "field_publication_year" => "2021"
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                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
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                    "field_covers" => array:1 [
                      0 => array:4 [ …4]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1065}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1066}
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                    "field_url" => "/10-klass/fizika/kasyanov-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1068}
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      #items: array:4 [
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                          #connection: "mysql"
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                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 4566
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Касьянов"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Валерий"
                            "field_patronymic" => "Алексеевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4566
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Касьянов"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Валерий"
                            "field_patronymic" => "Алексеевич"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#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" => 1389609
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "14. Силы 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" => "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 {#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" => 1389609
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "14. Силы электромагнитного взаимодействия неподвижных зарядов"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1153}
            "field_page_start" => "362"
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            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1154}
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          #dateFormat: null
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          #touches: []
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            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" => 1389614
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Закон Кулона"
            "field_branch_order" => "79"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1160
              #items: array:1 [
                0 => App\Models\Term {#1157
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
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                  #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"
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                      "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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                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Параграф"
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                      "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
            }
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            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1168
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                0 => App\Models\Branch {#1167
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                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
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                  #perPage: 15
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                  #attributes: array:24 [
                    "id" => 1389609
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                    "book" => Illuminate\Database\Eloquent\Collection {#1170
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                    }
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1171
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                  ]
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                }
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            "field_url" => null
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            0 => "*"
          ]
        }
        3 => App\Models\Branch {#1161
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
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          #attributes: array:24 [
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            "field_display_title" => "Задачи"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1158
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              #escapeWhenCastingToString: false
            }
            "field_page_start" => "373"
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            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1164
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                0 => App\Models\Book {#1120}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1177
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                0 => App\Models\Branch {#1176
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
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                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1178
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
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                    "book" => Illuminate\Database\Eloquent\Collection {#1179
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1180
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                  ]
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      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1071
      #items: array:2 [
        0 => App\Models\Element {#1099
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            "created_at" => "2026-04-10 13:58:26"
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            "edition" => Illuminate\Database\Eloquent\Collection {#1089
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                0 => App\Models\Edition {#1097
                  #connection: "mysql"
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                    "created_at" => "2026-04-10 13:58:26"
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                    "field_content_type" => "free"
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                    "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-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1096
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            "text" => "<p><strong>3.</strong> Два одинаковых шарика массой 44,1 г подвешены на нитях длиной 0,5 м в одной точке. При сообщении шарикам одинаковых избыточных зарядов они оттолкнулись друг от друга так, что угол между нитями стал равным 90°. Найдите значения избыточных зарядов на шариках.</p>"
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            ]
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            "edition" => Illuminate\Database\Eloquent\Collection {#1089}
            "task" => array:2 [
              "refs" => "1390408"
              "type" => "task"
            ]
            "text" => "<p><strong>3.</strong> Два одинаковых шарика массой 44,1 г подвешены на нитях длиной 0,5 м в одной точке. При сообщении шарикам одинаковых избыточных зарядов они оттолкнулись друг от друга так, что угол между нитями стал равным 90°. Найдите значения избыточных зарядов на шариках.</p>"
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            "text" => "<p><strong>Дано:</strong></p><p>Масса каждого шарика: $m = 44,1 \text{ г}$</p><p>Длина нити: $L = 0,5 \text{ м}$</p><p>Угол между нитями: $\theta = 90^\circ$</p><p>Заряды шариков одинаковы: $q_1 = q_2 = q$</p><p>Ускорение свободного падения: $g \approx 9,8 \text{ м/с}^2$</p><p>Коэффициент в законе Кулона: $k = 9 \cdot 10^9 \text{ Н} \cdot \text{м}^2/\text{Кл}^2$</p><p>Перевод в СИ:</p><p>$m = 44,1 \cdot 10^{-3} \text{ кг} = 0,0441 \text{ кг}$</p><p><strong>Найти:</strong></p><p>Значение заряда: $q$</p><p><strong>Решение:</strong></p><p>После того как шарикам сообщили заряды, они оттолкнулись и установились в положении равновесия. Это означает, что сумма всех сил, действующих на каждый шарик, равна нулю. Рассмотрим силы, действующие на один из шариков (например, правый):</p><ol><li>Сила тяжести $F_g = mg$, направленная вертикально вниз.</li><li>Сила натяжения нити $T$, направленная вдоль нити к точке подвеса.</li><li>Сила Кулона (электростатического отталкивания) $F_e$, направленная горизонтально от другого шарика.</li></ol><p>Поскольку система симметрична, угол каждой нити с вертикалью будет равен $\alpha = \frac{\theta}{2} = \frac{90^\circ}{2} = 45^\circ$.</p><p>Запишем условие равновесия в проекциях на горизонтальную (ось X) и вертикальную (ось Y) оси. Для этого разложим силу натяжения нити $T$ на компоненты:</p><ul><li>Вертикальная составляющая: $T_y = T \cos \alpha$</li><li>Горизонтальная составляющая: $T_x = T \sin \alpha$</li></ul><p>Условия равновесия:</p><p>По оси Y: $T_y - F_g = 0 \implies T \cos \alpha = mg$ (1)</p><p>По оси X: $F_e - T_x = 0 \implies F_e = T \sin \alpha$ (2)</p><p>Разделим уравнение (2) на уравнение (1), чтобы исключить неизвестную силу натяжения $T$:</p><p>$\frac{T \sin \alpha}{T \cos \alpha} = \frac{F_e}{mg}$</p><p>$\tan \alpha = \frac{F_e}{mg}$</p><p>Отсюда можно выразить силу Кулона:</p><p>$F_e = mg \tan \alpha$</p><p>Сила Кулона также определяется по формуле:</p><p>$F_e = k \frac{q_1 q_2}{r^2} = k \frac{q^2}{r^2}$, где $r$ - расстояние между шариками.</p><p>Найдем расстояние $r$ из геометрии. Оно равно двум горизонтальным катетам в треугольнике, образованном нитью, вертикалью и горизонталью. Длина катета равна $L \sin \alpha$.</p><p>$r = 2L \sin \alpha$</p><p>Приравняем два выражения для силы Кулона:</p><p>$mg \tan \alpha = k \frac{q^2}{(2L \sin \alpha)^2}$</p><p>Выразим отсюда искомый заряд $q$:</p><p>$q^2 = \frac{mg \tan \alpha \cdot (2L \sin \alpha)^2}{k} = \frac{4 L^2 \sin^2 \alpha \cdot mg \tan \alpha}{k}$</p><p>$q = \sqrt{\frac{4 L^2 \sin^2 \alpha \cdot mg \tan \alpha}{k}} = 2L \sin \alpha \sqrt{\frac{mg \tan \alpha}{k}}$</p><p>Подставим числовые значения. Учитывая, что $\alpha = 45^\circ$, имеем $\sin 45^\circ = \frac{\sqrt{2}}{2}$ и $\tan 45^\circ = 1$.</p><p>$q = 2 \cdot 0,5 \cdot \frac{\sqrt{2}}{2} \sqrt{\frac{0,0441 \cdot 9,8 \cdot 1}{9 \cdot 10^9}}$</p><p>$q = \frac{\sqrt{2}}{2} \sqrt{\frac{0,43218}{9 \cdot 10^9}} = \frac{\sqrt{2}}{2} \sqrt{0,04802 \cdot 10^{-9}}$</p><p>$q = \frac{\sqrt{2}}{2} \sqrt{48,02 \cdot 10^{-12}} \approx 0,7071 \cdot 6,93 \cdot 10^{-6} \approx 4,9 \cdot 10^{-6} \text{ Кл}$</p><p>Проведем вычисления другим, более точным способом, чтобы избежать промежуточных округлений:</p><p>$F_e = mg \tan(45^\circ) = 0,0441 \text{ кг} \cdot 9,8 \text{ м/с}^2 \cdot 1 = 0,43218 \text{ Н}$</p><p>$r = 2L \sin(45^\circ) = 2 \cdot 0,5 \text{ м} \cdot \frac{\sqrt{2}}{2} = \frac{\sqrt{2}}{2} \text{ м}$</p><p>$r^2 = (\frac{\sqrt{2}}{2})^2 = \frac{2}{4} = 0,5 \text{ м}^2$</p><p>Теперь из закона Кулона $F_e = k \frac{q^2}{r^2}$ найдем $q^2$:</p><p>$q^2 = \frac{F_e \cdot r^2}{k} = \frac{0,43218 \cdot 0,5}{9 \cdot 10^9} = \frac{0,21609}{9 \cdot 10^9} = 0,02401 \cdot 10^{-9} = 24,01 \cdot 10^{-12} \text{ Кл}^2$</p><p>$q = \sqrt{24,01 \cdot 10^{-12} \text{ Кл}^2} = 4,9 \cdot 10^{-6} \text{ Кл}$</p><p>Это значение можно также выразить в микрокулонах: $4,9$ мкКл.</p><p><strong>Ответ:</strong> значение избыточного заряда на каждом шарике равно $4,9 \cdot 10^{-6}$ Кл или $4,9$ мкКл.</p>"
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            "text" => "<p><strong>Дано:</strong></p><p>Масса каждого шарика: $m = 44,1 \text{ г}$</p><p>Длина нити: $L = 0,5 \text{ м}$</p><p>Угол между нитями: $\theta = 90^\circ$</p><p>Заряды шариков одинаковы: $q_1 = q_2 = q$</p><p>Ускорение свободного падения: $g \approx 9,8 \text{ м/с}^2$</p><p>Коэффициент в законе Кулона: $k = 9 \cdot 10^9 \text{ Н} \cdot \text{м}^2/\text{Кл}^2$</p><p>Перевод в СИ:</p><p>$m = 44,1 \cdot 10^{-3} \text{ кг} = 0,0441 \text{ кг}$</p><p><strong>Найти:</strong></p><p>Значение заряда: $q$</p><p><strong>Решение:</strong></p><p>После того как шарикам сообщили заряды, они оттолкнулись и установились в положении равновесия. Это означает, что сумма всех сил, действующих на каждый шарик, равна нулю. Рассмотрим силы, действующие на один из шариков (например, правый):</p><ol><li>Сила тяжести $F_g = mg$, направленная вертикально вниз.</li><li>Сила натяжения нити $T$, направленная вдоль нити к точке подвеса.</li><li>Сила Кулона (электростатического отталкивания) $F_e$, направленная горизонтально от другого шарика.</li></ol><p>Поскольку система симметрична, угол каждой нити с вертикалью будет равен $\alpha = \frac{\theta}{2} = \frac{90^\circ}{2} = 45^\circ$.</p><p>Запишем условие равновесия в проекциях на горизонтальную (ось X) и вертикальную (ось Y) оси. Для этого разложим силу натяжения нити $T$ на компоненты:</p><ul><li>Вертикальная составляющая: $T_y = T \cos \alpha$</li><li>Горизонтальная составляющая: $T_x = T \sin \alpha$</li></ul><p>Условия равновесия:</p><p>По оси Y: $T_y - F_g = 0 \implies T \cos \alpha = mg$ (1)</p><p>По оси X: $F_e - T_x = 0 \implies F_e = T \sin \alpha$ (2)</p><p>Разделим уравнение (2) на уравнение (1), чтобы исключить неизвестную силу натяжения $T$:</p><p>$\frac{T \sin \alpha}{T \cos \alpha} = \frac{F_e}{mg}$</p><p>$\tan \alpha = \frac{F_e}{mg}$</p><p>Отсюда можно выразить силу Кулона:</p><p>$F_e = mg \tan \alpha$</p><p>Сила Кулона также определяется по формуле:</p><p>$F_e = k \frac{q_1 q_2}{r^2} = k \frac{q^2}{r^2}$, где $r$ - расстояние между шариками.</p><p>Найдем расстояние $r$ из геометрии. Оно равно двум горизонтальным катетам в треугольнике, образованном нитью, вертикалью и горизонталью. Длина катета равна $L \sin \alpha$.</p><p>$r = 2L \sin \alpha$</p><p>Приравняем два выражения для силы Кулона:</p><p>$mg \tan \alpha = k \frac{q^2}{(2L \sin \alpha)^2}$</p><p>Выразим отсюда искомый заряд $q$:</p><p>$q^2 = \frac{mg \tan \alpha \cdot (2L \sin \alpha)^2}{k} = \frac{4 L^2 \sin^2 \alpha \cdot mg \tan \alpha}{k}$</p><p>$q = \sqrt{\frac{4 L^2 \sin^2 \alpha \cdot mg \tan \alpha}{k}} = 2L \sin \alpha \sqrt{\frac{mg \tan \alpha}{k}}$</p><p>Подставим числовые значения. Учитывая, что $\alpha = 45^\circ$, имеем $\sin 45^\circ = \frac{\sqrt{2}}{2}$ и $\tan 45^\circ = 1$.</p><p>$q = 2 \cdot 0,5 \cdot \frac{\sqrt{2}}{2} \sqrt{\frac{0,0441 \cdot 9,8 \cdot 1}{9 \cdot 10^9}}$</p><p>$q = \frac{\sqrt{2}}{2} \sqrt{\frac{0,43218}{9 \cdot 10^9}} = \frac{\sqrt{2}}{2} \sqrt{0,04802 \cdot 10^{-9}}$</p><p>$q = \frac{\sqrt{2}}{2} \sqrt{48,02 \cdot 10^{-12}} \approx 0,7071 \cdot 6,93 \cdot 10^{-6} \approx 4,9 \cdot 10^{-6} \text{ Кл}$</p><p>Проведем вычисления другим, более точным способом, чтобы избежать промежуточных округлений:</p><p>$F_e = mg \tan(45^\circ) = 0,0441 \text{ кг} \cdot 9,8 \text{ м/с}^2 \cdot 1 = 0,43218 \text{ Н}$</p><p>$r = 2L \sin(45^\circ) = 2 \cdot 0,5 \text{ м} \cdot \frac{\sqrt{2}}{2} = \frac{\sqrt{2}}{2} \text{ м}$</p><p>$r^2 = (\frac{\sqrt{2}}{2})^2 = \frac{2}{4} = 0,5 \text{ м}^2$</p><p>Теперь из закона Кулона $F_e = k \frac{q^2}{r^2}$ найдем $q^2$:</p><p>$q^2 = \frac{F_e \cdot r^2}{k} = \frac{0,43218 \cdot 0,5}{9 \cdot 10^9} = \frac{0,21609}{9 \cdot 10^9} = 0,02401 \cdot 10^{-9} = 24,01 \cdot 10^{-12} \text{ Кл}^2$</p><p>$q = \sqrt{24,01 \cdot 10^{-12} \text{ Кл}^2} = 4,9 \cdot 10^{-6} \text{ Кл}$</p><p>Это значение можно также выразить в микрокулонах: $4,9$ мкКл.</p><p><strong>Ответ:</strong> значение избыточного заряда на каждом шарике равно $4,9 \cdot 10^{-6}$ Кл или $4,9$ мкКл.</p>"
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№3 (с. 373)
Условие. №3 (с. 373)
скриншот условия
Физика, 10 класс Учебник, автор: Касьянов Валерий Алексеевич, издательство Просвещение, Москва, 2021, белого цвета, страница 373, номер 3, Условие

3. Два одинаковых шарика массой 44,1 г подвешены на нитях длиной 0,5 м в одной точке. При сообщении шарикам одинаковых избыточных зарядов они оттолкнулись друг от друга так, что угол между нитями стал равным 90°. Найдите значения избыточных зарядов на шариках.

Решение. №3 (с. 373)

Дано:

Масса каждого шарика: $m = 44,1 \text{ г}$

Длина нити: $L = 0,5 \text{ м}$

Угол между нитями: $\theta = 90^\circ$

Заряды шариков одинаковы: $q_1 = q_2 = q$

Ускорение свободного падения: $g \approx 9,8 \text{ м/с}^2$

Коэффициент в законе Кулона: $k = 9 \cdot 10^9 \text{ Н} \cdot \text{м}^2/\text{Кл}^2$

Перевод в СИ:

$m = 44,1 \cdot 10^{-3} \text{ кг} = 0,0441 \text{ кг}$

Найти:

Значение заряда: $q$

Решение:

После того как шарикам сообщили заряды, они оттолкнулись и установились в положении равновесия. Это означает, что сумма всех сил, действующих на каждый шарик, равна нулю. Рассмотрим силы, действующие на один из шариков (например, правый):

  1. Сила тяжести $F_g = mg$, направленная вертикально вниз.
  2. Сила натяжения нити $T$, направленная вдоль нити к точке подвеса.
  3. Сила Кулона (электростатического отталкивания) $F_e$, направленная горизонтально от другого шарика.

Поскольку система симметрична, угол каждой нити с вертикалью будет равен $\alpha = \frac{\theta}{2} = \frac{90^\circ}{2} = 45^\circ$.

Запишем условие равновесия в проекциях на горизонтальную (ось X) и вертикальную (ось Y) оси. Для этого разложим силу натяжения нити $T$ на компоненты:

  • Вертикальная составляющая: $T_y = T \cos \alpha$
  • Горизонтальная составляющая: $T_x = T \sin \alpha$

Условия равновесия:

По оси Y: $T_y - F_g = 0 \implies T \cos \alpha = mg$ (1)

По оси X: $F_e - T_x = 0 \implies F_e = T \sin \alpha$ (2)

Разделим уравнение (2) на уравнение (1), чтобы исключить неизвестную силу натяжения $T$:

$\frac{T \sin \alpha}{T \cos \alpha} = \frac{F_e}{mg}$

$\tan \alpha = \frac{F_e}{mg}$

Отсюда можно выразить силу Кулона:

$F_e = mg \tan \alpha$

Сила Кулона также определяется по формуле:

$F_e = k \frac{q_1 q_2}{r^2} = k \frac{q^2}{r^2}$, где $r$ - расстояние между шариками.

Найдем расстояние $r$ из геометрии. Оно равно двум горизонтальным катетам в треугольнике, образованном нитью, вертикалью и горизонталью. Длина катета равна $L \sin \alpha$.

$r = 2L \sin \alpha$

Приравняем два выражения для силы Кулона:

$mg \tan \alpha = k \frac{q^2}{(2L \sin \alpha)^2}$

Выразим отсюда искомый заряд $q$:

$q^2 = \frac{mg \tan \alpha \cdot (2L \sin \alpha)^2}{k} = \frac{4 L^2 \sin^2 \alpha \cdot mg \tan \alpha}{k}$

$q = \sqrt{\frac{4 L^2 \sin^2 \alpha \cdot mg \tan \alpha}{k}} = 2L \sin \alpha \sqrt{\frac{mg \tan \alpha}{k}}$

Подставим числовые значения. Учитывая, что $\alpha = 45^\circ$, имеем $\sin 45^\circ = \frac{\sqrt{2}}{2}$ и $\tan 45^\circ = 1$.

$q = 2 \cdot 0,5 \cdot \frac{\sqrt{2}}{2} \sqrt{\frac{0,0441 \cdot 9,8 \cdot 1}{9 \cdot 10^9}}$

$q = \frac{\sqrt{2}}{2} \sqrt{\frac{0,43218}{9 \cdot 10^9}} = \frac{\sqrt{2}}{2} \sqrt{0,04802 \cdot 10^{-9}}$

$q = \frac{\sqrt{2}}{2} \sqrt{48,02 \cdot 10^{-12}} \approx 0,7071 \cdot 6,93 \cdot 10^{-6} \approx 4,9 \cdot 10^{-6} \text{ Кл}$

Проведем вычисления другим, более точным способом, чтобы избежать промежуточных округлений:

$F_e = mg \tan(45^\circ) = 0,0441 \text{ кг} \cdot 9,8 \text{ м/с}^2 \cdot 1 = 0,43218 \text{ Н}$

$r = 2L \sin(45^\circ) = 2 \cdot 0,5 \text{ м} \cdot \frac{\sqrt{2}}{2} = \frac{\sqrt{2}}{2} \text{ м}$

$r^2 = (\frac{\sqrt{2}}{2})^2 = \frac{2}{4} = 0,5 \text{ м}^2$

Теперь из закона Кулона $F_e = k \frac{q^2}{r^2}$ найдем $q^2$:

$q^2 = \frac{F_e \cdot r^2}{k} = \frac{0,43218 \cdot 0,5}{9 \cdot 10^9} = \frac{0,21609}{9 \cdot 10^9} = 0,02401 \cdot 10^{-9} = 24,01 \cdot 10^{-12} \text{ Кл}^2$

$q = \sqrt{24,01 \cdot 10^{-12} \text{ Кл}^2} = 4,9 \cdot 10^{-6} \text{ Кл}$

Это значение можно также выразить в микрокулонах: $4,9$ мкКл.

Ответ: значение избыточного заряда на каждом шарике равно $4,9 \cdot 10^{-6}$ Кл или $4,9$ мкКл.

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Мы подготовили для вас ответ c подробным объяснением домашего задания по физике за 10 класс, для упражнения номер 3 расположенного на странице 373 к учебнику 2021 года издания для учащихся школ и гимназий.

Теперь на нашем сайте ГДЗ.ТОП вы всегда легко и бесплатно найдёте условие с правильным ответом на вопрос «Как решить ДЗ» и «Как сделать» задание по физике к упражнению №3 (с. 373), автора: Касьянов (Валерий Алексеевич), ФГОС (старый) углублённый уровень обучения учебного пособия издательства Просвещение.