Номер 11.9, страница 63 - гдз по физике 8-11 класс учебник, задачник Гельфгат, Генденштейн

Физика, 8-11 класс Учебник, задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2005

Авторы: Гельфгат И. М., Генденштейн Л. Э., Кирик Л. А.

Тип: Учебник, задачник

Издательство: Илекса

Год издания: 2005 - 2026

Цвет обложки: синий мужчина в красном, летит на черном шаре

ISBN: 978-5-89237-332-6

Задачи. Молекулярная физика. 11. Законы термодинамики - номер 11.9, страница 63.

App\Models\Task {#1024 // resources/views/models/task/default.blade.php
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                          #connection: "mysql"
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                        1 => App\Models\Term {#1037
                          #connection: "mysql"
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                        2 => App\Models\Term {#1038
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                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik, zadachnik"
                          ]
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                          #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 {#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: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"
                          ]
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                          #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 {#1051
                      #items: array:1 [
                        0 => App\Models\Term {#1052
                          #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 {#1053
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1054
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1055
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1056
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => "6"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1057
                      #items: array:1 [
                        0 => App\Models\Term {#1058
                          #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" => 35
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "исправленное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "ispravlennoe"
                          ]
                          #original: array:6 [
                            "id" => 35
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "исправленное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "ispravlennoe"
                          ]
                          #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 {#1059
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "мужчина в красном, летит на черном шаре"
                    "field_publication_year" => "2005"
                    "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" => "1001"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_08/gelfgat-u/"
                    "field_isbn" => "978-5-89237-332-6"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                        "alt" => ""
                        "width" => "1813"
                        "height" => "2441"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1060
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1061
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1062
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/8-klass/fizika/ileksa-gelfgat-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1063
                      #items: array:1 [
                        0 => App\Models\Term {#1064
                          #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 [ …6]
                            "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 [ …6]
                            "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" => 379
                      "subject" => 556
                      "class_subject" => 492
                    ]
                  ]
                  #original: array:50 [
                    "id" => 5401
                    "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 {#1032}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1035}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1040}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1042}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1046}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1047}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1049}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1051}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1053}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1054}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1055}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1056}
                    "field_publication_number" => "6"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1057}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1059}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "мужчина в красном, летит на черном шаре"
                    "field_publication_year" => "2005"
                    "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" => "1001"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_08/gelfgat-u/"
                    "field_isbn" => "978-5-89237-332-6"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                        "alt" => ""
                        "width" => "1813"
                        "height" => "2441"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1060}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1061}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1062}
                    "field_url" => "/8-klass/fizika/ileksa-gelfgat-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1063}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 379
                      "subject" => 556
                      "class_subject" => 492
                    ]
                  ]
                  #changes: []
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                  #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 {#1065
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1287866
            "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 {#333}
            "field_page_start" => "5"
            "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 {#1033}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1065}
          ]
          #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 {#1066
      #items: array:3 [
        0 => App\Models\Branch {#1023}
        1 => App\Models\Branch {#1067
          #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" => 1287876
            "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 {#1068
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "49"
            "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 {#1069
              #items: array:1 [
                0 => App\Models\Book {#1030}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1070
              #items: array:1 [
                0 => App\Models\Branch {#1071
                  #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" => 1287866
                    "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 {#1072 …2}
                    "field_page_start" => "5"
                    "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 {#1073 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1107 …2}
                  ]
                  #original: array:24 [
                    "id" => 1287866
                    "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 {#1072 …2}
                    "field_page_start" => "5"
                    "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 {#1073 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1107 …2}
                  ]
                  #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" => 1287876
            "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 {#1068}
            "field_page_start" => "49"
            "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 {#1069}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1070}
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1108
          #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" => 1287879
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "11. Законы термодинамики"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1109
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "62"
            "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" => []
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                0 => App\Models\Book {#1111
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                    "field_cover_description" => "мужчина в красном, летит на черном шаре"
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                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1134 …2}
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                    "field_cover_description" => "мужчина в красном, летит на черном шаре"
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                    "field_cover" => array:1 [ …1]
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                    "breadcrumbs" => array:3 [ …3]
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            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1144
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                0 => App\Models\Branch {#1145
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                  #attributes: array:24 [
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    "content" => Illuminate\Database\Eloquent\Collection {#1219
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                  #attributes: array:21 [
                    "id" => 5410
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1223 …2}
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                    "field_content_mode" => "text, image"
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                    "field_page_content_text_checked" => "0"
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            "task" => array:2 [
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            "text" => "<p><strong>11.9.</strong> Калориметр содержит $m_1 = 250$ г воды при температуре $t_1 = 15\ ^{\circ}\text{C}$.</p><p>В воду бросили $m_2 = 20$ г мокрого снега.</p><p>В результате температура в калориметре понизилась на $\Delta t = 5\ ^{\circ}\text{C}$.</p><p>Сколько воды было в снеге?</p>"
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                "width" => "1424"
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            "edition" => Illuminate\Database\Eloquent\Collection {#1221}
            "task" => array:2 [
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            "text" => "<p><strong>11.9.</strong> Калориметр содержит $m_1 = 250$ г воды при температуре $t_1 = 15\ ^{\circ}\text{C}$.</p><p>В воду бросили $m_2 = 20$ г мокрого снега.</p><p>В результате температура в калориметре понизилась на $\Delta t = 5\ ^{\circ}\text{C}$.</p><p>Сколько воды было в снеге?</p>"
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        1 => App\Models\Element {#1228
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        2 => App\Models\Element {#1236
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            "created_at" => "2026-04-10 13:58:26"
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            "text" => "<p><strong>Дано:</strong></p><p>$m_1 = 250$ г</p><p>$t_1 = 15$ °C</p><p>$m_2 = 20$ г</p><p>$\Delta t = 5$ °C</p><p>Так как снег мокрый, его температура $t_{снега} = 0$ °C.</p><p>Удельная теплоемкость воды $c = 4200 \frac{Дж}{кг \cdot °C}$.</p><p>Удельная теплота плавления льда $\lambda = 3.3 \cdot 10^5 \frac{Дж}{кг}$.</p><p><em>Перевод в систему СИ:</em></p><p>$m_1 = 250 \text{ г} = 0.25 \text{ кг}$</p><p>$m_2 = 20 \text{ г} = 0.02 \text{ кг}$</p><p><strong>Найти:</strong></p><p>$m_{воды\_в\_снеге}$ — массу воды в мокром снеге.</p><p><strong>Решение:</strong></p><p><strong>1.</strong> Сначала определим конечную температуру смеси в калориметре. Начальная температура воды была $t_1$, и она понизилась на $\Delta t$.</p><p>$t_{кон} = t_1 - \Delta t = 15°C - 5°C = 10°C$</p><p><strong>2.</strong> Запишем уравнение теплового баланса для системы. Будем считать калориметр идеальным, то есть теплообмен с окружающей средой отсутствует. Количество теплоты, отданное теплой водой при охлаждении ($Q_{отд}$), равно количеству теплоты, полученному мокрым снегом для плавления и нагрева ($Q_{получ}$).</p><p>$Q_{отд} = Q_{получ}$</p><p><strong>3.</strong> Количество теплоты, которое отдала вода в калориметре, охлаждаясь от $t_1$ до $t_{кон}$:</p><p>$Q_{отд} = c \cdot m_1 \cdot (t_1 - t_{кон})$</p><p><strong>4.</strong> Мокрый снег является смесью льда (массой $m_{льда}$) и воды (массой $m_{воды\_в\_снеге}$) при температуре $\text{0}$ °C. Количество теплоты, полученное снегом, состоит из двух частей:<br>а) теплоты, необходимой для плавления льда, содержащегося в снеге: $Q_{плавл} = \lambda \cdot m_{льда}$.<br>б) теплоты, необходимой для нагрева всей массы $m_2$ (исходной воды из снега и воды, образовавшейся после таяния льда) от $\text{0}$ °C до конечной температуры $t_{кон}$: $Q_{нагрев} = c \cdot m_2 \cdot (t_{кон} - 0) = c \cdot m_2 \cdot t_{кон}$.</p><p>Следовательно, общее полученное тепло:</p><p>$Q_{получ} = \lambda \cdot m_{льда} + c \cdot m_2 \cdot t_{кон}$</p><p><strong>5.</strong> Теперь приравняем отданную и полученную теплоту:</p><p>$c \cdot m_1 \cdot (t_1 - t_{кон}) = \lambda \cdot m_{льда} + c \cdot m_2 \cdot t_{кон}$</p><p><strong>6.</strong> Из этого уравнения выразим массу льда $m_{льда}$:</p><p>$\lambda \cdot m_{льда} = c \cdot m_1 \cdot (t_1 - t_{кон}) - c \cdot m_2 \cdot t_{кон}$</p><p>$m_{льда} = \frac{c \cdot (m_1 (t_1 - t_{кон}) - m_2 t_{кон})}{\lambda}$</p><p><strong>7.</strong> Подставим числовые значения в полученную формулу:</p><p>$m_{льда} = \frac{4200 \frac{Дж}{кг \cdot °C} \cdot (0.25 \text{ кг} \cdot (15°C - 10°C) - 0.02 \text{ кг} \cdot 10°C)}{3.3 \cdot 10^5 \frac{Дж}{кг}}$</p><p>$m_{льда} = \frac{4200 \cdot (0.25 \cdot 5 - 0.02 \cdot 10)}{3.3 \cdot 10^5} \text{ кг} = \frac{4200 \cdot (1.25 - 0.2)}{3.3 \cdot 10^5} \text{ кг}$</p><p>$m_{льда} = \frac{4200 \cdot 1.05}{3.3 \cdot 10^5} \text{ кг} = \frac{4410}{330000} \text{ кг} \approx 0.01336 \text{ кг}$</p><p>В граммах это составляет: $m_{льда} \approx 13.4$ г.</p><p><strong>8.</strong> Зная массу льда и общую массу мокрого снега $m_2$, найдем массу воды в нем:</p><p>$m_{воды\_в\_снеге} = m_2 - m_{льда}$</p><p>$m_{воды\_в\_снеге} = 20 \text{ г} - 13.4 \text{ г} = 6.6 \text{ г}$</p><p><strong>Ответ:</strong> в снеге было 6.6 г воды.</p>"
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            "text" => "<p><strong>Дано:</strong></p><p>$m_1 = 250$ г</p><p>$t_1 = 15$ °C</p><p>$m_2 = 20$ г</p><p>$\Delta t = 5$ °C</p><p>Так как снег мокрый, его температура $t_{снега} = 0$ °C.</p><p>Удельная теплоемкость воды $c = 4200 \frac{Дж}{кг \cdot °C}$.</p><p>Удельная теплота плавления льда $\lambda = 3.3 \cdot 10^5 \frac{Дж}{кг}$.</p><p><em>Перевод в систему СИ:</em></p><p>$m_1 = 250 \text{ г} = 0.25 \text{ кг}$</p><p>$m_2 = 20 \text{ г} = 0.02 \text{ кг}$</p><p><strong>Найти:</strong></p><p>$m_{воды\_в\_снеге}$ — массу воды в мокром снеге.</p><p><strong>Решение:</strong></p><p><strong>1.</strong> Сначала определим конечную температуру смеси в калориметре. Начальная температура воды была $t_1$, и она понизилась на $\Delta t$.</p><p>$t_{кон} = t_1 - \Delta t = 15°C - 5°C = 10°C$</p><p><strong>2.</strong> Запишем уравнение теплового баланса для системы. Будем считать калориметр идеальным, то есть теплообмен с окружающей средой отсутствует. Количество теплоты, отданное теплой водой при охлаждении ($Q_{отд}$), равно количеству теплоты, полученному мокрым снегом для плавления и нагрева ($Q_{получ}$).</p><p>$Q_{отд} = Q_{получ}$</p><p><strong>3.</strong> Количество теплоты, которое отдала вода в калориметре, охлаждаясь от $t_1$ до $t_{кон}$:</p><p>$Q_{отд} = c \cdot m_1 \cdot (t_1 - t_{кон})$</p><p><strong>4.</strong> Мокрый снег является смесью льда (массой $m_{льда}$) и воды (массой $m_{воды\_в\_снеге}$) при температуре $\text{0}$ °C. Количество теплоты, полученное снегом, состоит из двух частей:<br>а) теплоты, необходимой для плавления льда, содержащегося в снеге: $Q_{плавл} = \lambda \cdot m_{льда}$.<br>б) теплоты, необходимой для нагрева всей массы $m_2$ (исходной воды из снега и воды, образовавшейся после таяния льда) от $\text{0}$ °C до конечной температуры $t_{кон}$: $Q_{нагрев} = c \cdot m_2 \cdot (t_{кон} - 0) = c \cdot m_2 \cdot t_{кон}$.</p><p>Следовательно, общее полученное тепло:</p><p>$Q_{получ} = \lambda \cdot m_{льда} + c \cdot m_2 \cdot t_{кон}$</p><p><strong>5.</strong> Теперь приравняем отданную и полученную теплоту:</p><p>$c \cdot m_1 \cdot (t_1 - t_{кон}) = \lambda \cdot m_{льда} + c \cdot m_2 \cdot t_{кон}$</p><p><strong>6.</strong> Из этого уравнения выразим массу льда $m_{льда}$:</p><p>$\lambda \cdot m_{льда} = c \cdot m_1 \cdot (t_1 - t_{кон}) - c \cdot m_2 \cdot t_{кон}$</p><p>$m_{льда} = \frac{c \cdot (m_1 (t_1 - t_{кон}) - m_2 t_{кон})}{\lambda}$</p><p><strong>7.</strong> Подставим числовые значения в полученную формулу:</p><p>$m_{льда} = \frac{4200 \frac{Дж}{кг \cdot °C} \cdot (0.25 \text{ кг} \cdot (15°C - 10°C) - 0.02 \text{ кг} \cdot 10°C)}{3.3 \cdot 10^5 \frac{Дж}{кг}}$</p><p>$m_{льда} = \frac{4200 \cdot (0.25 \cdot 5 - 0.02 \cdot 10)}{3.3 \cdot 10^5} \text{ кг} = \frac{4200 \cdot (1.25 - 0.2)}{3.3 \cdot 10^5} \text{ кг}$</p><p>$m_{льда} = \frac{4200 \cdot 1.05}{3.3 \cdot 10^5} \text{ кг} = \frac{4410}{330000} \text{ кг} \approx 0.01336 \text{ кг}$</p><p>В граммах это составляет: $m_{льда} \approx 13.4$ г.</p><p><strong>8.</strong> Зная массу льда и общую массу мокрого снега $m_2$, найдем массу воды в нем:</p><p>$m_{воды\_в\_снеге} = m_2 - m_{льда}$</p><p>$m_{воды\_в\_снеге} = 20 \text{ г} - 13.4 \text{ г} = 6.6 \text{ г}$</p><p><strong>Ответ:</strong> в снеге было 6.6 г воды.</p>"
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№11.9 (с. 63)
Условие. №11.9 (с. 63)
скриншот условия
Физика, 8-11 класс Учебник, задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2005, страница 63, номер 11.9, Условие

11.9. Калориметр содержит $m_1 = 250$ г воды при температуре $t_1 = 15\ ^{\circ}\text{C}$.

В воду бросили $m_2 = 20$ г мокрого снега.

В результате температура в калориметре понизилась на $\Delta t = 5\ ^{\circ}\text{C}$.

Сколько воды было в снеге?

Решение. №11.9 (с. 63)
Физика, 8-11 класс Учебник, задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2005, страница 63, номер 11.9, Решение
Решение 2. №11.9 (с. 63)

Дано:

$m_1 = 250$ г

$t_1 = 15$ °C

$m_2 = 20$ г

$\Delta t = 5$ °C

Так как снег мокрый, его температура $t_{снега} = 0$ °C.

Удельная теплоемкость воды $c = 4200 \frac{Дж}{кг \cdot °C}$.

Удельная теплота плавления льда $\lambda = 3.3 \cdot 10^5 \frac{Дж}{кг}$.

Перевод в систему СИ:

$m_1 = 250 \text{ г} = 0.25 \text{ кг}$

$m_2 = 20 \text{ г} = 0.02 \text{ кг}$

Найти:

$m_{воды\_в\_снеге}$ — массу воды в мокром снеге.

Решение:

1. Сначала определим конечную температуру смеси в калориметре. Начальная температура воды была $t_1$, и она понизилась на $\Delta t$.

$t_{кон} = t_1 - \Delta t = 15°C - 5°C = 10°C$

2. Запишем уравнение теплового баланса для системы. Будем считать калориметр идеальным, то есть теплообмен с окружающей средой отсутствует. Количество теплоты, отданное теплой водой при охлаждении ($Q_{отд}$), равно количеству теплоты, полученному мокрым снегом для плавления и нагрева ($Q_{получ}$).

$Q_{отд} = Q_{получ}$

3. Количество теплоты, которое отдала вода в калориметре, охлаждаясь от $t_1$ до $t_{кон}$:

$Q_{отд} = c \cdot m_1 \cdot (t_1 - t_{кон})$

4. Мокрый снег является смесью льда (массой $m_{льда}$) и воды (массой $m_{воды\_в\_снеге}$) при температуре $\text{0}$ °C. Количество теплоты, полученное снегом, состоит из двух частей:
а) теплоты, необходимой для плавления льда, содержащегося в снеге: $Q_{плавл} = \lambda \cdot m_{льда}$.
б) теплоты, необходимой для нагрева всей массы $m_2$ (исходной воды из снега и воды, образовавшейся после таяния льда) от $\text{0}$ °C до конечной температуры $t_{кон}$: $Q_{нагрев} = c \cdot m_2 \cdot (t_{кон} - 0) = c \cdot m_2 \cdot t_{кон}$.

Следовательно, общее полученное тепло:

$Q_{получ} = \lambda \cdot m_{льда} + c \cdot m_2 \cdot t_{кон}$

5. Теперь приравняем отданную и полученную теплоту:

$c \cdot m_1 \cdot (t_1 - t_{кон}) = \lambda \cdot m_{льда} + c \cdot m_2 \cdot t_{кон}$

6. Из этого уравнения выразим массу льда $m_{льда}$:

$\lambda \cdot m_{льда} = c \cdot m_1 \cdot (t_1 - t_{кон}) - c \cdot m_2 \cdot t_{кон}$

$m_{льда} = \frac{c \cdot (m_1 (t_1 - t_{кон}) - m_2 t_{кон})}{\lambda}$

7. Подставим числовые значения в полученную формулу:

$m_{льда} = \frac{4200 \frac{Дж}{кг \cdot °C} \cdot (0.25 \text{ кг} \cdot (15°C - 10°C) - 0.02 \text{ кг} \cdot 10°C)}{3.3 \cdot 10^5 \frac{Дж}{кг}}$

$m_{льда} = \frac{4200 \cdot (0.25 \cdot 5 - 0.02 \cdot 10)}{3.3 \cdot 10^5} \text{ кг} = \frac{4200 \cdot (1.25 - 0.2)}{3.3 \cdot 10^5} \text{ кг}$

$m_{льда} = \frac{4200 \cdot 1.05}{3.3 \cdot 10^5} \text{ кг} = \frac{4410}{330000} \text{ кг} \approx 0.01336 \text{ кг}$

В граммах это составляет: $m_{льда} \approx 13.4$ г.

8. Зная массу льда и общую массу мокрого снега $m_2$, найдем массу воды в нем:

$m_{воды\_в\_снеге} = m_2 - m_{льда}$

$m_{воды\_в\_снеге} = 20 \text{ г} - 13.4 \text{ г} = 6.6 \text{ г}$

Ответ: в снеге было 6.6 г воды.

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