Номер 6, страница 182 - гдз по физике 9 класс учебник Изергин

Физика, 9 класс Учебник, автор: Изергин Эдуард Тимофеевич, издательство Русское слово, Москва, 2019

Авторы: Изергин Э. Т.

Тип: Учебник

Серия: инновационная школа

Издательство: Русское слово

Год издания: 2019 - 2026

Цвет обложки: синий

ISBN: 978-5-533-01069-6

Глава V. Физика атома и атомного ядра. Проверим свои знания по теме главы V - номер 6, страница 182.

App\Models\Task {#1024 // resources/views/models/task/default.blade.php
  #connection: "mysql"
  #table: "tasks"
  #primaryKey: "id"
  #keyType: "int"
  +incrementing: true
  #with: []
  #withCount: []
  +preventsLazyLoading: false
  #perPage: 15
  +exists: true
  +wasRecentlyCreated: false
  #escapeWhenCastingToString: false
  #attributes: array:24 [
    "id" => 1439917
    "created_at" => "2026-04-10 13:58:26"
    "updated_at" => null
    "field_page_start" => "182"
    "field_page_end" => null
    "field_url" => "/9-klass/fizika/izergin-uchebnik/glav5-6"
    "field_display_title" => "6"
    "field_outside_task" => null
    "field_task_type" => Illuminate\Database\Eloquent\Collection {#331
      #items: array:1 [
        0 => App\Models\Term {#1029
          #connection: "mysql"
          #table: "terms"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: false
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
          #original: array:6 [
            "id" => 26
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "name" => "номер"
            "field_cases" => array:6 [
              "field_accusative_case" => "номер"
              "field_creative_case" => "номером"
              "field_dative_case" => "номеру"
              "field_genitive_case" => "номера"
              "field_nominative_case" => "номер"
              "field_prepositional_case" => "номере"
            ]
            "field_short_name" => ""
          ]
          #changes: []
          #casts: []
          #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
    "field_match" => null
    "breadcrumbs" => []
    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1026
      #items: []
      #escapeWhenCastingToString: false
    }
    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#342
      #items: array:1 [
        0 => App\Models\Branch {#1023
          #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" => 1439582
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Физика атома и атомного ядра"
            "field_branch_order" => "V"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#333
              #items: array:1 [
                0 => App\Models\Term {#1033
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:7 [
                    "id" => 29
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Глава"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Главу"
                      "field_creative_case" => "Главой"
                      "field_dative_case" => "Главе"
                      "field_genitive_case" => "Главы"
                      "field_nominative_case" => "Глава"
                      "field_prepositional_case" => "Главе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => null
                  ]
                  #original: array:7 [
                    "id" => 29
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Глава"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Главу"
                      "field_creative_case" => "Главой"
                      "field_dative_case" => "Главе"
                      "field_genitive_case" => "Главы"
                      "field_nominative_case" => "Глава"
                      "field_prepositional_case" => "Главе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => null
                  ]
                  #changes: []
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                  #classCastCache: []
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                  #dateFormat: null
                  #appends: []
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                  +timestamps: true
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                  #hidden: []
                  #visible: []
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                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "157"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1030
              #items: array:1 [
                0 => App\Models\Book {#1032
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:50 [
                    "id" => 4169
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1034
                      #items: array:1 [
                        0 => App\Models\Term {#1035
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [
                            "id" => 6493
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Физика"
                            "field_abbreviated_name" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "физику"
                              "field_creative_case" => "физикой"
                              "field_dative_case" => "физике"
                              "field_genitive_case" => "физики"
                              "field_nominative_case" => "физика"
                              "field_prepositional_case" => "физике"
                            ]
                            "field_foreign_lang_name" => null
                            "field_short_name" => null
                            "field_subject_type" => "technical_subject"
                            "field_translit" => "fizika"
                          ]
                          #original: array:10 [
                            "id" => 6493
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Физика"
                            "field_abbreviated_name" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "физику"
                              "field_creative_case" => "физикой"
                              "field_dative_case" => "физике"
                              "field_genitive_case" => "физики"
                              "field_nominative_case" => "физика"
                              "field_prepositional_case" => "физике"
                            ]
                            "field_foreign_lang_name" => null
                            "field_short_name" => null
                            "field_subject_type" => "technical_subject"
                            "field_translit" => "fizika"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
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                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1036
                      #items: array:1 [
                        0 => App\Models\Term {#1037
                          #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" => 5458
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "9"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "девятый"
                              "field_creative_case" => "девятым"
                              "field_dative_case" => "девятому"
                              "field_genitive_case" => "девятого"
                              "field_nominative_case" => "девятый"
                              "field_prepositional_case" => "девятом"
                            ]
                            "field_translit" => "devjatyj"
                          ]
                          #original: array:6 [
                            "id" => 5458
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "9"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "девятый"
                              "field_creative_case" => "девятым"
                              "field_dative_case" => "девятому"
                              "field_genitive_case" => "девятого"
                              "field_nominative_case" => "девятый"
                              "field_prepositional_case" => "девятом"
                            ]
                            "field_translit" => "devjatyj"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
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                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1038
                      #items: array:1 [
                        0 => App\Models\Term {#1039
                          #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" => 5176
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Русское слово"
                            "field_cases" => null
                            "field_translit" => "russkoe slovo"
                          ]
                          #original: array:6 [
                            "id" => 5176
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Русское слово"
                            "field_cases" => null
                            "field_translit" => "russkoe slovo"
                          ]
                          #changes: []
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                          #hidden: []
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                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1040
                      #items: array:1 [
                        0 => App\Models\Term {#1041
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 4491
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Изергин"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Эдуард"
                            "field_patronymic" => "Тимофеевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4491
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Изергин"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Эдуард"
                            "field_patronymic" => "Тимофеевич"
                            "field_surname_rp" => null
                          ]
                          #changes: []
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                          #attributeCastCache: []
                          #dateFormat: null
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                          #touches: []
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                          #hidden: []
                          #visible: []
                          #fillable: []
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                          ]
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                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1042
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1043
                      #items: array:1 [
                        0 => App\Models\Term {#1044
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
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                          +exists: true
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                          #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 [
                              "field_accusative_case" => "учебник"
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                              "field_genitive_case" => "учебника"
                              "field_nominative_case" => "учебник"
                              "field_prepositional_case" => "учебнике"
                            ]
                            "field_plural_form" => null
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                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik"
                          ]
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                            "field_translit" => "uchebnik"
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                      ]
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                    "field_country" => Illuminate\Database\Eloquent\Collection {#1045
                      #items: array:1 [
                        0 => App\Models\Term {#1046
                          #connection: "mysql"
                          #table: "terms"
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                          #keyType: "int"
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                          #attributes: array:6 [
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
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                            "created_at" => "2026-04-10 13:58:26"
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                    "field_city" => Illuminate\Database\Eloquent\Collection {#1047
                      #items: array:1 [
                        0 => App\Models\Term {#1048
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
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                          #attributes: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
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                            ]
                            "field_translit" => "moskva"
                          ]
                          #original: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
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                            ]
                            "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 {#1049
                      #items: array:1 [
                        0 => App\Models\Term {#1050
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:8 [
                            "id" => 4715
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "инновационная школа"
                            "field_cases" => null
                            "field_foreign_lang_series" => null
                            "field_transcription_eng" => null
                            "field_translit" => "innovacionnaya shkola"
                          ]
                          #original: array:8 [
                            "id" => 4715
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "инновационная школа"
                            "field_cases" => null
                            "field_foreign_lang_series" => null
                            "field_transcription_eng" => null
                            "field_translit" => "innovacionnaya shkola"
                          ]
                          #changes: []
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                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
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                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1051
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1052
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1053
                      #items: array:1 [
                        0 => App\Models\Term {#1054
                          #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 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_color" => 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 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_color" => 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" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1055
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1056
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для 9 класса общеобразовательных организаций"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "388"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/izergin-u/"
                    "field_isbn" => "978-5-533-01069-6"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_09/izergin-u/covers/cover1.webp?ts=1759162386"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/izergin-u/covers/cover1.webp?ts=1759162386"
                        "alt" => ""
                        "width" => "1881"
                        "height" => "2502"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1057
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1058
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1059
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/9-klass/fizika/izergin-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1060
                      #items: array:1 [
                        0 => App\Models\Term {#1061
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "siniy"
                          ]
                          #original: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "siniy"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
                  #original: array:50 [
                    "id" => 4169
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1034}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1036}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1038}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1040}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1042}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1043}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1045}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1047}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1049}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1051}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1052}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1053}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1055}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1056}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2019"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебник для 9 класса общеобразовательных организаций"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "388"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/izergin-u/"
                    "field_isbn" => "978-5-533-01069-6"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_09/izergin-u/covers/cover1.webp?ts=1759162386"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/izergin-u/covers/cover1.webp?ts=1759162386"
                        "alt" => ""
                        "width" => "1881"
                        "height" => "2502"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1057}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1058}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1059}
                    "field_url" => "/9-klass/fizika/izergin-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1060}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
                  #changes: []
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                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1062
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1439582
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Физика атома и атомного ядра"
            "field_branch_order" => "V"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#333}
            "field_page_start" => "157"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1030}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1062}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1063
      #items: array:2 [
        0 => App\Models\Branch {#1023}
        1 => App\Models\Branch {#1064
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1439590
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Проверим свои знания по теме главы V"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1065
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "182"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1066
              #items: array:1 [
                0 => App\Models\Book {#1032}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1067
              #items: array:1 [
                0 => App\Models\Branch {#1068
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [
                    "id" => 1439582
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Физика атома и атомного ядра"
                    "field_branch_order" => "V"
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1069
                      #items: array:1 [
                        0 => App\Models\Term {#1033}
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_page_start" => "157"
                    "field_branch_display" => "0"
                    "field_branch_expanded" => "0"
                    "field_display_branch_in_title" => "1"
                    "field_display_task_interval" => "0"
                    "field_display_branch_page" => "1"
                    "field_branch_title_in_content" => "0"
                    "field_navigation_title" => null
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1070
                      #items: array:1 [
                        0 => App\Models\Book {#1032}
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1071
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                  ]
                  #original: array:24 [
                    "id" => 1439582
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Физика атома и атомного ядра"
                    "field_branch_order" => "V"
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1069}
                    "field_page_start" => "157"
                    "field_branch_display" => "0"
                    "field_branch_expanded" => "0"
                    "field_display_branch_in_title" => "1"
                    "field_display_task_interval" => "0"
                    "field_display_branch_page" => "1"
                    "field_branch_title_in_content" => "0"
                    "field_navigation_title" => null
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1070}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1071}
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1439590
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Проверим свои знания по теме главы V"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1065}
            "field_page_start" => "182"
            "field_branch_display" => "0"
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            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
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            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1066}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1067}
          ]
          #changes: []
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          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
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          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1072
      #items: array:2 [
        0 => App\Models\Element {#1073
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:7 [
            "id" => 1707519
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1074
              #items: array:1 [
                0 => App\Models\Edition {#1075
                  #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" => 6139
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1076
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            "text" => "<p><strong>6.</strong> Радиоактивный изотоп железа ${}_{26}^{59}\text{Fe}$ имеет период полураспада 45 суток. Это означает, что</p><p><strong>1)</strong> за 90 суток распадутся все наличные ядра железа-59</p><p><strong>2)</strong> каждое ядро железа-59 распадается каждые 45 суток</p><p><strong>3)</strong> за 45 суток распадётся половина из большого числа радиоактивных ядер железа-59</p><p><strong>4)</strong> за 45 суток распадутся все ядра радиоактивного железа из большого их числа</p>"
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            "text" => "<p><strong>Решение</strong></p><p>Период полураспада ($T_{1/2}$) — это промежуток времени, в течение которого в среднем распадается половина от большого начального числа радиоактивных ядер. В условии задачи дано, что период полураспада изотопа железа $_{26}^{59}Fe$ составляет 45 суток.</p><p>Рассмотрим каждый из предложенных вариантов ответа:</p><p><strong>1)</strong> за 90 суток распадутся все наличные ядра железа-59</p><p>Это утверждение неверно. 90 суток — это два периода полураспада ($2 \cdot 45$ суток). За первый период полураспада (45 суток) число ядер уменьшится в 2 раза. За второй период полураспада — ещё в 2 раза. Таким образом, через 90 суток останется $1/4$ от начального числа ядер, а распадётся $3/4$. Согласно закону радиоактивного распада $N(t) = N_0 \cdot 2^{-t/T_{1/2}}$, где $N_0$ — начальное число ядер, а $N(t)$ — число нераспавшихся ядер через время $\text{t}$. Через 90 суток: $N(90) = N_0 \cdot 2^{-90/45} = N_0 \cdot 2^{-2} = N_0/4$. Полный распад всех ядер теоретически занимает бесконечное время.</p><p><strong>2)</strong> каждое ядро железа-59 распадается каждые 45 суток</p><p>Это утверждение неверно. Распад отдельного ядра является случайным событием, и невозможно предсказать, когда именно оно произойдёт. Период полураспада — это статистическая величина, которая описывает поведение большого ансамбля ядер, а не каждого ядра в отдельности. Кроме того, каждое ядро может распасться только один раз.</p><p><strong>3)</strong> за 45 суток распадётся половина из большого числа радиоактивных ядер железа-59</p><p>Это утверждение верно. Оно в точности соответствует определению периода полураспада. За время, равное одному периоду полураспада, распадается половина из большого числа имеющихся радиоактивных ядер.</p><p><strong>4)</strong> за 45 суток распадутся все ядра радиоактивного железа из большого их числа</p><p>Это утверждение неверно. Как следует из определения, за один период полураспада распадается только половина, а не все ядра.</p><p><strong>Ответ:</strong> 3</p>"
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            "text" => "<p><strong>Решение</strong></p><p>Период полураспада ($T_{1/2}$) — это промежуток времени, в течение которого в среднем распадается половина от большого начального числа радиоактивных ядер. В условии задачи дано, что период полураспада изотопа железа $_{26}^{59}Fe$ составляет 45 суток.</p><p>Рассмотрим каждый из предложенных вариантов ответа:</p><p><strong>1)</strong> за 90 суток распадутся все наличные ядра железа-59</p><p>Это утверждение неверно. 90 суток — это два периода полураспада ($2 \cdot 45$ суток). За первый период полураспада (45 суток) число ядер уменьшится в 2 раза. За второй период полураспада — ещё в 2 раза. Таким образом, через 90 суток останется $1/4$ от начального числа ядер, а распадётся $3/4$. Согласно закону радиоактивного распада $N(t) = N_0 \cdot 2^{-t/T_{1/2}}$, где $N_0$ — начальное число ядер, а $N(t)$ — число нераспавшихся ядер через время $\text{t}$. Через 90 суток: $N(90) = N_0 \cdot 2^{-90/45} = N_0 \cdot 2^{-2} = N_0/4$. Полный распад всех ядер теоретически занимает бесконечное время.</p><p><strong>2)</strong> каждое ядро железа-59 распадается каждые 45 суток</p><p>Это утверждение неверно. Распад отдельного ядра является случайным событием, и невозможно предсказать, когда именно оно произойдёт. Период полураспада — это статистическая величина, которая описывает поведение большого ансамбля ядер, а не каждого ядра в отдельности. Кроме того, каждое ядро может распасться только один раз.</p><p><strong>3)</strong> за 45 суток распадётся половина из большого числа радиоактивных ядер железа-59</p><p>Это утверждение верно. Оно в точности соответствует определению периода полураспада. За время, равное одному периоду полураспада, распадается половина из большого числа имеющихся радиоактивных ядер.</p><p><strong>4)</strong> за 45 суток распадутся все ядра радиоактивного железа из большого их числа</p><p>Это утверждение неверно. Как следует из определения, за один период полураспада распадается только половина, а не все ядра.</p><p><strong>Ответ:</strong> 3</p>"
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                2 => App\Models\Task {#1279
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                3 => App\Models\Task {#1345
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№6 (с. 182)
Условие. №6 (с. 182)
скриншот условия
Физика, 9 класс Учебник, автор: Изергин Эдуард Тимофеевич, издательство Русское слово, Москва, 2019, страница 182, номер 6, Условие

6. Радиоактивный изотоп железа ${}_{26}^{59}\text{Fe}$ имеет период полураспада 45 суток. Это означает, что

1) за 90 суток распадутся все наличные ядра железа-59

2) каждое ядро железа-59 распадается каждые 45 суток

3) за 45 суток распадётся половина из большого числа радиоактивных ядер железа-59

4) за 45 суток распадутся все ядра радиоактивного железа из большого их числа

Решение. №6 (с. 182)

Решение

Период полураспада ($T_{1/2}$) — это промежуток времени, в течение которого в среднем распадается половина от большого начального числа радиоактивных ядер. В условии задачи дано, что период полураспада изотопа железа $_{26}^{59}Fe$ составляет 45 суток.

Рассмотрим каждый из предложенных вариантов ответа:

1) за 90 суток распадутся все наличные ядра железа-59

Это утверждение неверно. 90 суток — это два периода полураспада ($2 \cdot 45$ суток). За первый период полураспада (45 суток) число ядер уменьшится в 2 раза. За второй период полураспада — ещё в 2 раза. Таким образом, через 90 суток останется $1/4$ от начального числа ядер, а распадётся $3/4$. Согласно закону радиоактивного распада $N(t) = N_0 \cdot 2^{-t/T_{1/2}}$, где $N_0$ — начальное число ядер, а $N(t)$ — число нераспавшихся ядер через время $\text{t}$. Через 90 суток: $N(90) = N_0 \cdot 2^{-90/45} = N_0 \cdot 2^{-2} = N_0/4$. Полный распад всех ядер теоретически занимает бесконечное время.

2) каждое ядро железа-59 распадается каждые 45 суток

Это утверждение неверно. Распад отдельного ядра является случайным событием, и невозможно предсказать, когда именно оно произойдёт. Период полураспада — это статистическая величина, которая описывает поведение большого ансамбля ядер, а не каждого ядра в отдельности. Кроме того, каждое ядро может распасться только один раз.

3) за 45 суток распадётся половина из большого числа радиоактивных ядер железа-59

Это утверждение верно. Оно в точности соответствует определению периода полураспада. За время, равное одному периоду полураспада, распадается половина из большого числа имеющихся радиоактивных ядер.

4) за 45 суток распадутся все ядра радиоактивного железа из большого их числа

Это утверждение неверно. Как следует из определения, за один период полураспада распадается только половина, а не все ядра.

Ответ: 3

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