Номер 2, страница 319 - 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

Молекулярная физика. 12. Твёрдое тело. Параграф 67. Кристаллизация и плавление твёрдых тел. Задачи - номер 2, страница 319.

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                          #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" => 1389517
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Молекулярная физика"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1119}
            "field_page_start" => "219"
            "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" => 1389580
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "12. Твёрдое тело"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1153
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "316"
            "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" => 1389580
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "12. Твёрдое тело"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1153}
            "field_page_start" => "316"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1154}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1155}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
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          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1156
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
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          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
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          #attributes: array:24 [
            "id" => 1389581
            "created_at" => "2026-04-10 13:58:26"
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                0 => App\Models\Term {#1157
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
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                  #withCount: []
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                  #attributes: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
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                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
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                  ]
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                    0 => "*"
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              ]
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            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1159
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                0 => App\Models\Book {#1120}
              ]
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            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1168
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                0 => App\Models\Branch {#1167
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
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                  +exists: true
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                  #escapeWhenCastingToString: false
                  #attributes: array:24 [
                    "id" => 1389580
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "12. Твёрдое тело"
                    "field_branch_order" => null
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1169 …2}
                    "field_page_start" => "316"
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                    "field_navigation_title" => null
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                    "field_h1" => null
                    "field_description_top" => null
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                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1170 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1171 …2}
                  ]
                  #original: array:24 [
                    "id" => 1389580
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                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1169 …2}
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                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1170 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1171 …2}
                  ]
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                  #attributeCastCache: []
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                  #visible: []
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
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          #original: array:24 [
            "id" => 1389581
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            "updated_at" => null
            "field_display_title" => "Кристаллизация и плавление твёрдых тел"
            "field_branch_order" => "67"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1160}
            "field_page_start" => "316"
            "field_branch_display" => "0"
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            "field_display_branch_in_title" => "1"
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1159}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1168}
          ]
          #changes: []
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          #attributeCastCache: []
          #dateFormat: null
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          +timestamps: true
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          #hidden: []
          #visible: []
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          #guarded: array:1 [
            0 => "*"
          ]
        }
        3 => App\Models\Branch {#1161
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:24 [
            "id" => 1389583
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Задачи"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1158
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "319"
            "field_branch_display" => "0"
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            "field_display_branch_in_title" => "1"
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            "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 {#1164
              #items: array:1 [
                0 => App\Models\Book {#1120}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1177
              #items: array:1 [
                0 => App\Models\Branch {#1176
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:24 [
                    "id" => 1389581
                    "created_at" => "2026-04-10 13:58:26"
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                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1178 …2}
                    "field_page_start" => "316"
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                    "field_display_branch_in_title" => "1"
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                    "field_h1" => null
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                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1179 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1180 …2}
                  ]
                  #original: array:24 [
                    "id" => 1389581
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Кристаллизация и плавление твёрдых тел"
                    "field_branch_order" => "67"
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1178 …2}
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                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1179 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1180 …2}
                  ]
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
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          #original: array:24 [
            "id" => 1389583
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Задачи"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1158}
            "field_page_start" => "319"
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            "field_navigation_title" => null
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            "field_h1" => null
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1164}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1177}
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            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1071
      #items: array:2 [
        0 => App\Models\Element {#1099
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
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          #attributes: array:7 [
            "id" => 1640606
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1089
              #items: array:1 [
                0 => App\Models\Edition {#1097
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
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                  +exists: true
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                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 5810
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1095 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1096 …2}
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                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1093 …2}
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                    "title" => "Условие"
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1095 …2}
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                  ]
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                    0 => "*"
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              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1390298"
              "type" => "task"
            ]
            "text" => "<p><strong>2.</strong> Через какой промежуток времени под лучами весеннего солнца расплавится кусок льда площадью 2 м<sup>2</sup> и толщиной 1 см, имеющий температуру 0 °С? Энергия солнечного излучения, падающего на единицу площади за единицу времени, равна 350 Вт/м<sup>2</sup>.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "2-1.jpg"
                "alt" => null
                "width" => "1679"
                "height" => 257
                "path" => "/media/fizika_10/kasyanov-u/0-67zad/2-1.webp?ts=1757958123"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1640606
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1089}
            "task" => array:2 [
              "refs" => "1390298"
              "type" => "task"
            ]
            "text" => "<p><strong>2.</strong> Через какой промежуток времени под лучами весеннего солнца расплавится кусок льда площадью 2 м<sup>2</sup> и толщиной 1 см, имеющий температуру 0 °С? Энергия солнечного излучения, падающего на единицу площади за единицу времени, равна 350 Вт/м<sup>2</sup>.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "2-1.jpg"
                "alt" => null
                "width" => "1679"
                "height" => 257
                "path" => "/media/fizika_10/kasyanov-u/0-67zad/2-1.webp?ts=1757958123"
              ]
            ]
          ]
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          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Element {#1092
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 1693310
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1083
              #items: array:1 [
                0 => App\Models\Edition {#1091
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 6145
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1087 …2}
                    "field_content_type" => "free"
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                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1088 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1085 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1086 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6145
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1087 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
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                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1088 …2}
                    "field_comment" => null
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            "text" => "<p><strong>Дано:</strong></p><p>Площадь льда $S = 2 \text{ м}^2$</p><p>Толщина льда $h = 1 \text{ см}$</p><p>Начальная температура льда $T = 0 \text{ °C}$</p><p>Интенсивность солнечного излучения $I = 350 \text{ Вт/м}^2$</p><p>Удельная теплота плавления льда $\lambda = 3.3 \cdot 10^5 \text{ Дж/кг}$ (справочное значение)</p><p>Плотность льда $\rho = 900 \text{ кг/м}^3$ (справочное значение)</p><p>Перевод в систему СИ:<br>$h = 1 \text{ см} = 0.01 \text{ м}$<br>$I = 350 \text{ Вт/м}^2 = 350 \frac{\text{Дж}}{\text{с} \cdot \text{м}^2}$</p><p><strong>Найти:</strong></p><p>Промежуток времени $t$</p><p><strong>Решение:</strong></p><p>Для того чтобы кусок льда полностью расплавился, ему необходимо сообщить количество теплоты $Q$, равное произведению его массы $m$ на удельную теплоту плавления льда $\lambda$. Поскольку лед уже находится при температуре плавления ($0 \text{ °C}$), нагревать его не нужно.</p><p>Формула для количества теплоты, необходимого для плавления: $Q = \lambda \cdot m$</p><p>Массу льда $m$ можно найти через его объем $V$ и плотность $\rho$. Объем, в свою очередь, равен произведению площади $S$ на толщину $h$: $m = \rho \cdot V = \rho \cdot S \cdot h$</p><p>Подставим выражение для массы в формулу для теплоты: $Q = \lambda \cdot \rho \cdot S \cdot h$</p><p>Энергия $E$, которую лед получает от солнечного излучения за время $t$, равна произведению мощности излучения $P$ на время $t$. Мощность $P$ — это произведение интенсивности излучения $I$ на площадь $S$, на которую оно падает. $E = P \cdot t = (I \cdot S) \cdot t$</p><p>Приравняем количество теплоты, необходимое для плавления, к энергии, полученной от Солнца, предполагая, что вся солнечная энергия поглощается льдом и идет на его плавление: $Q = E$ $\lambda \cdot \rho \cdot S \cdot h = I \cdot S \cdot t$</p><p>Из этого уравнения выразим время $t$. Можно заметить, что площадь $S$ сокращается, то есть время плавления льда данной толщины не зависит от его площади. $t = \frac{\lambda \cdot \rho \cdot h}{I}$</p><p>Подставим числовые значения в итоговую формулу: $t = \frac{3.3 \cdot 10^5 \frac{\text{Дж}}{\text{кг}} \cdot 900 \frac{\text{кг}}{\text{м}^3} \cdot 0.01 \text{ м}}{350 \frac{\text{Дж}}{\text{с} \cdot \text{м}^2}}$</p><p>$t = \frac{2970000}{350} \text{ с} \approx 8485.7 \text{ с}$</p><p>Переведем полученное время в более удобные единицы: $8485.7 \text{ с} \approx 141.4 \text{ мин} \approx 2.36 \text{ часа}$ Более точно: 2 часа, 21 минута и 26 секунд.</p><p><strong>Ответ:</strong> время, необходимое для плавления льда, составляет примерно $8485.7$ секунд или 2 часа 21 минуту 26 секунд.</p>"
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            "text" => "<p><strong>Дано:</strong></p><p>Площадь льда $S = 2 \text{ м}^2$</p><p>Толщина льда $h = 1 \text{ см}$</p><p>Начальная температура льда $T = 0 \text{ °C}$</p><p>Интенсивность солнечного излучения $I = 350 \text{ Вт/м}^2$</p><p>Удельная теплота плавления льда $\lambda = 3.3 \cdot 10^5 \text{ Дж/кг}$ (справочное значение)</p><p>Плотность льда $\rho = 900 \text{ кг/м}^3$ (справочное значение)</p><p>Перевод в систему СИ:<br>$h = 1 \text{ см} = 0.01 \text{ м}$<br>$I = 350 \text{ Вт/м}^2 = 350 \frac{\text{Дж}}{\text{с} \cdot \text{м}^2}$</p><p><strong>Найти:</strong></p><p>Промежуток времени $t$</p><p><strong>Решение:</strong></p><p>Для того чтобы кусок льда полностью расплавился, ему необходимо сообщить количество теплоты $Q$, равное произведению его массы $m$ на удельную теплоту плавления льда $\lambda$. Поскольку лед уже находится при температуре плавления ($0 \text{ °C}$), нагревать его не нужно.</p><p>Формула для количества теплоты, необходимого для плавления: $Q = \lambda \cdot m$</p><p>Массу льда $m$ можно найти через его объем $V$ и плотность $\rho$. Объем, в свою очередь, равен произведению площади $S$ на толщину $h$: $m = \rho \cdot V = \rho \cdot S \cdot h$</p><p>Подставим выражение для массы в формулу для теплоты: $Q = \lambda \cdot \rho \cdot S \cdot h$</p><p>Энергия $E$, которую лед получает от солнечного излучения за время $t$, равна произведению мощности излучения $P$ на время $t$. Мощность $P$ — это произведение интенсивности излучения $I$ на площадь $S$, на которую оно падает. $E = P \cdot t = (I \cdot S) \cdot t$</p><p>Приравняем количество теплоты, необходимое для плавления, к энергии, полученной от Солнца, предполагая, что вся солнечная энергия поглощается льдом и идет на его плавление: $Q = E$ $\lambda \cdot \rho \cdot S \cdot h = I \cdot S \cdot t$</p><p>Из этого уравнения выразим время $t$. Можно заметить, что площадь $S$ сокращается, то есть время плавления льда данной толщины не зависит от его площади. $t = \frac{\lambda \cdot \rho \cdot h}{I}$</p><p>Подставим числовые значения в итоговую формулу: $t = \frac{3.3 \cdot 10^5 \frac{\text{Дж}}{\text{кг}} \cdot 900 \frac{\text{кг}}{\text{м}^3} \cdot 0.01 \text{ м}}{350 \frac{\text{Дж}}{\text{с} \cdot \text{м}^2}}$</p><p>$t = \frac{2970000}{350} \text{ с} \approx 8485.7 \text{ с}$</p><p>Переведем полученное время в более удобные единицы: $8485.7 \text{ с} \approx 141.4 \text{ мин} \approx 2.36 \text{ часа}$ Более точно: 2 часа, 21 минута и 26 секунд.</p><p><strong>Ответ:</strong> время, необходимое для плавления льда, составляет примерно $8485.7$ секунд или 2 часа 21 минуту 26 секунд.</p>"
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№2 (с. 319)
Условие. №2 (с. 319)
скриншот условия
Физика, 10 класс Учебник, автор: Касьянов Валерий Алексеевич, издательство Просвещение, Москва, 2021, белого цвета, страница 319, номер 2, Условие

2. Через какой промежуток времени под лучами весеннего солнца расплавится кусок льда площадью 2 м2 и толщиной 1 см, имеющий температуру 0 °С? Энергия солнечного излучения, падающего на единицу площади за единицу времени, равна 350 Вт/м2.

Решение. №2 (с. 319)

Дано:

Площадь льда $S = 2 \text{ м}^2$

Толщина льда $h = 1 \text{ см}$

Начальная температура льда $T = 0 \text{ °C}$

Интенсивность солнечного излучения $I = 350 \text{ Вт/м}^2$

Удельная теплота плавления льда $\lambda = 3.3 \cdot 10^5 \text{ Дж/кг}$ (справочное значение)

Плотность льда $\rho = 900 \text{ кг/м}^3$ (справочное значение)

Перевод в систему СИ:
$h = 1 \text{ см} = 0.01 \text{ м}$
$I = 350 \text{ Вт/м}^2 = 350 \frac{\text{Дж}}{\text{с} \cdot \text{м}^2}$

Найти:

Промежуток времени $t$

Решение:

Для того чтобы кусок льда полностью расплавился, ему необходимо сообщить количество теплоты $Q$, равное произведению его массы $m$ на удельную теплоту плавления льда $\lambda$. Поскольку лед уже находится при температуре плавления ($0 \text{ °C}$), нагревать его не нужно.

Формула для количества теплоты, необходимого для плавления: $Q = \lambda \cdot m$

Массу льда $m$ можно найти через его объем $V$ и плотность $\rho$. Объем, в свою очередь, равен произведению площади $S$ на толщину $h$: $m = \rho \cdot V = \rho \cdot S \cdot h$

Подставим выражение для массы в формулу для теплоты: $Q = \lambda \cdot \rho \cdot S \cdot h$

Энергия $E$, которую лед получает от солнечного излучения за время $t$, равна произведению мощности излучения $P$ на время $t$. Мощность $P$ — это произведение интенсивности излучения $I$ на площадь $S$, на которую оно падает. $E = P \cdot t = (I \cdot S) \cdot t$

Приравняем количество теплоты, необходимое для плавления, к энергии, полученной от Солнца, предполагая, что вся солнечная энергия поглощается льдом и идет на его плавление: $Q = E$ $\lambda \cdot \rho \cdot S \cdot h = I \cdot S \cdot t$

Из этого уравнения выразим время $t$. Можно заметить, что площадь $S$ сокращается, то есть время плавления льда данной толщины не зависит от его площади. $t = \frac{\lambda \cdot \rho \cdot h}{I}$

Подставим числовые значения в итоговую формулу: $t = \frac{3.3 \cdot 10^5 \frac{\text{Дж}}{\text{кг}} \cdot 900 \frac{\text{кг}}{\text{м}^3} \cdot 0.01 \text{ м}}{350 \frac{\text{Дж}}{\text{с} \cdot \text{м}^2}}$

$t = \frac{2970000}{350} \text{ с} \approx 8485.7 \text{ с}$

Переведем полученное время в более удобные единицы: $8485.7 \text{ с} \approx 141.4 \text{ мин} \approx 2.36 \text{ часа}$ Более точно: 2 часа, 21 минута и 26 секунд.

Ответ: время, необходимое для плавления льда, составляет примерно $8485.7$ секунд или 2 часа 21 минуту 26 секунд.

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