Номер 18.3, страница 134 - гдз по физике 10-11 класс задачник Гельфгат, Генденштейн

Физика, 10-11 класс Задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2008, красного цвета

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

Тип: Задачник

Издательство: Илекса

Год издания: 2008 - 2026

Уровень обучения: профильный

Цвет обложки: красный лупа, парень едет на велосипеде

ISBN: 978-5-89237-252-7

Молекулярная физика и термодинамика. Термодинамика. 18. Тепловые двигатели. Упражнения - номер 18.3, страница 134.

App\Models\Task {#1030 // resources/views/models/task/default.blade.php
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                              "field_nominative_case" => "задачник"
                              "field_prepositional_case" => "задачнике"
                            ]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "zadachnik"
                          ]
                          #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 {#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" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "rossiya"
                          ]
                          #original: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "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 {#1065
                      #items: array:1 [
                        0 => App\Models\Term {#1066
                          #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 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "moskva"
                          ]
                          #original: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "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 {#1067
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1068
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1069
                      #items: array:1 [
                        0 => App\Models\Term {#1070
                          #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" => 40
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "профильный"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "профильный"
                              "field_creative_case" => "профильным"
                              "field_dative_case" => "профильному"
                              "field_genitive_case" => "профильного"
                              "field_nominative_case" => "профильный"
                              "field_prepositional_case" => "профильном"
                            ]
                            "field_translit" => "profilnyy"
                          ]
                          #original: array:6 [
                            "id" => 40
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "профильный"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "профильный"
                              "field_creative_case" => "профильным"
                              "field_dative_case" => "профильному"
                              "field_genitive_case" => "профильного"
                              "field_nominative_case" => "профильный"
                              "field_prepositional_case" => "профильном"
                            ]
                            "field_translit" => "profilnyy"
                          ]
                          #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 {#1071
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1072
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1073
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "лупа, парень едет на велосипеде"
                    "field_publication_year" => "2008"
                    "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" => "459"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_10/gelfgat-z/"
                    "field_isbn" => "978-5-89237-252-7"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_10/gelfgat-z/covers/cover1.webp?ts=1756049816"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_10/gelfgat-z/covers/cover1.webp?ts=1756049816"
                        "alt" => ""
                        "width" => "1566"
                        "height" => "2412"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1074
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1075
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1076
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/10-klass/fizika/gelfgat-zadachnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1077
                      #items: array:1 [
                        0 => App\Models\Term {#1078
                          #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" => 46
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "красный"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "красный"
                              "field_creative_case" => "красным"
                              "field_dative_case" => "красному"
                              "field_genitive_case" => "красного"
                              "field_nominative_case" => "красный"
                              "field_prepositional_case" => "красном"
                            ]
                            "field_translit" => "krasnyy"
                          ]
                          #original: array:6 [
                            "id" => 46
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "красный"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "красный"
                              "field_creative_case" => "красным"
                              "field_dative_case" => "красному"
                              "field_genitive_case" => "красного"
                              "field_nominative_case" => "красный"
                              "field_prepositional_case" => "красном"
                            ]
                            "field_translit" => "krasnyy"
                          ]
                          #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" => 5400
                    "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 {#1050}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1051}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1054}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1056}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1060}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1061}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1063}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1065}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1067}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1068}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1069}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1071}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1072}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1073}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "лупа, парень едет на велосипеде"
                    "field_publication_year" => "2008"
                    "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" => "459"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_10/gelfgat-z/"
                    "field_isbn" => "978-5-89237-252-7"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_10/gelfgat-z/covers/cover1.webp?ts=1756049816"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_10/gelfgat-z/covers/cover1.webp?ts=1756049816"
                        "alt" => ""
                        "width" => "1566"
                        "height" => "2412"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1074}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1075}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1076}
                    "field_url" => "/10-klass/fizika/gelfgat-zadachnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1077}
                    "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 {#1079
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1319310
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Молекулярная физика и термодинамика"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1047}
            "field_page_start" => "104"
            "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 {#1081}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1079}
          ]
          #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 {#1111
      #items: array:4 [
        0 => App\Models\Branch {#1121
          #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" => 1319310
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Молекулярная физика и термодинамика"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1122
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "104"
            "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 {#1123
              #items: array:1 [
                0 => App\Models\Book {#1048}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1124
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1319310
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Молекулярная физика и термодинамика"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1122}
            "field_page_start" => "104"
            "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 {#1123}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1124}
          ]
          #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 {#1125
          #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" => 1319321
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Термодинамика"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1126
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "126"
            "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 {#1127
              #items: array:1 [
                0 => App\Models\Book {#1048}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1128
              #items: array:1 [
                0 => App\Models\Branch {#1045}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1319321
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        }
        2 => App\Models\Branch {#1129
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
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            "created_at" => "2026-04-10 13:58:26"
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            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1140
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                0 => App\Models\Branch {#1139
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                  #table: "branches"
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        }
        3 => App\Models\Branch {#1133
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          #primaryKey: "id"
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                0 => App\Models\Branch {#1148
                  #connection: "mysql"
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                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1152
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    "content" => Illuminate\Database\Eloquent\Collection {#1038
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        0 => App\Models\Element {#1102
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          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
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            "edition" => Illuminate\Database\Eloquent\Collection {#1092
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                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
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                    "id" => 5430
                    "created_at" => "2026-04-10 13:58:26"
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                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1098
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                          #connection: "mysql"
                          #table: "terms"
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                          #attributes: array:6 [ …6]
                          #original: array:6 [ …6]
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                    "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 {#1099
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1097
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1096
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                      #escapeWhenCastingToString: false
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            "task" => array:2 [
              "refs" => "1319603"
              "type" => "task"
            ]
            "text" => "<p><strong>18.3.</strong> На рисунке показан цикл из двух изохор и двух изобар. Найдите КПД цикла, если рабочее тело — одноатомный идеальный газ.</p><p>&#9745; 17 %.</p><p><strong><em>Решение.</em></strong> КПД цикла $ \eta = A'/Q $. Совершенная за цикл работа $A'$ численно равна площади прямоугольника: $ A' = 2p_0V_0 $. Полученное за цикл от нагревателя количество теплоты $ Q = Q_{1-2} + Q_{2-3} $. Из уравнения Клапейрона получаем $ T_2 = 2T_1 $, $ T_3 = 6T_1 $. Используя результаты решения задачи 17.6, находим:</p><p>$ Q_{1-2} = \nu C_V(T_2 - T_1) = 3\nu RT_1/2 $, $ Q_{2-3} = \nu C_p(T_3 - T_2) = 10\nu RT_1 $.</p><p>Здесь $ \nu $ — количество вещества. Подставляя полученные значения в формулу для КПД и используя соотношение $ p_0V_0 = \nu RT_1 $, получаем $ \eta = 4/23 \approx 0,17 $.</p>"
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                "width" => "1269"
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          #original: array:7 [
            "id" => 1493813
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1092}
            "task" => array:2 [
              "refs" => "1319603"
              "type" => "task"
            ]
            "text" => "<p><strong>18.3.</strong> На рисунке показан цикл из двух изохор и двух изобар. Найдите КПД цикла, если рабочее тело — одноатомный идеальный газ.</p><p>&#9745; 17 %.</p><p><strong><em>Решение.</em></strong> КПД цикла $ \eta = A'/Q $. Совершенная за цикл работа $A'$ численно равна площади прямоугольника: $ A' = 2p_0V_0 $. Полученное за цикл от нагревателя количество теплоты $ Q = Q_{1-2} + Q_{2-3} $. Из уравнения Клапейрона получаем $ T_2 = 2T_1 $, $ T_3 = 6T_1 $. Используя результаты решения задачи 17.6, находим:</p><p>$ Q_{1-2} = \nu C_V(T_2 - T_1) = 3\nu RT_1/2 $, $ Q_{2-3} = \nu C_p(T_3 - T_2) = 10\nu RT_1 $.</p><p>Здесь $ \nu $ — количество вещества. Подставляя полученные значения в формулу для КПД и используя соотношение $ p_0V_0 = \nu RT_1 $, получаем $ \eta = 4/23 \approx 0,17 $.</p>"
            "img" => array:2 [
              0 => array:5 [
                "name" => "3-1.jpg"
                "alt" => null
                "width" => "1413"
                "height" => 791
                "path" => "/media/fizika_10/gelfgat-z/0-18/3-1.webp?ts=1756251076"
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              1 => array:5 [
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            "text" => "<p><strong>Дано:</strong><br>Циклический процесс 1-2-3-4-1.<br>Рабочее тело - одноатомный идеальный газ.<br>Параметры состояний в узловых точках цикла (согласно графику):<br>Точка 1: $p_1 = p_0$, $V_1 = V_0$.<br>Точка 2: $p_2 = 2p_0$, $V_2 = V_0$.<br>Точка 3: $p_3 = 2p_0$, $V_3 = 3V_0$.<br>Точка 4: $p_4 = p_0$, $V_4 = 3V_0$.</p><p><strong>Найти:</strong><br>КПД цикла $\eta$.</p><p><strong>Решение:</strong><br>Коэффициент полезного действия (КПД) теплового двигателя определяется как отношение полезной работы $A'$, совершенной газом за цикл, к количеству теплоты $Q_{нагр}$, полученному от нагревателя:<br>$\eta = \frac{A'}{Q_{нагр}}$</p><p><strong>1.</strong> Полезная работа $A'$ за цикл численно равна площади фигуры, ограниченной графиком цикла на диаграмме в координатах p-V. В данном случае фигура является прямоугольником.<br>$A' = (p_2 - p_1) \cdot (V_3 - V_2) = (2p_0 - p_0) \cdot (3V_0 - V_0) = p_0 \cdot 2V_0 = 2p_0V_0$.</p><p><strong>2.</strong> Количество теплоты $Q_{нагр}$ газ получает на тех участках цикла, где его температура увеличивается. Согласно уравнению состояния идеального газа $pV = \nu RT$, температура растет при увеличении произведения $pV$.<br>- Участок 1-2 (изохорное нагревание): объем постоянен ($V=V_0$), давление растет от $p_0$ до $2p_0$. Произведение $pV$ увеличивается, следовательно, газ получает теплоту $Q_{1-2}$.<br>- Участок 2-3 (изобарное расширение): давление постоянно ($p=2p_0$), объем растет от $V_0$ до $3V_0$. Произведение $pV$ увеличивается, следовательно, газ получает теплоту $Q_{2-3}$.<br>- На участках 3-4 и 4-1 произведение $pV$ уменьшается, значит, температура падает, и газ отдает теплоту холодильнику.<br>Таким образом, общее количество теплоты, полученное от нагревателя, равно:<br>$Q_{нагр} = Q_{1-2} + Q_{2-3}$.</p><p><strong>3.</strong> Рассчитаем количество теплоты для каждого участка по первому началу термодинамики: $Q = \Delta U + A$. Для одноатомного идеального газа изменение внутренней энергии равно $\Delta U = \frac{3}{2}\nu R \Delta T = \frac{3}{2}\Delta(pV)$.<br>Для изохорного процесса 1-2 работа $A_{1-2}=0$.<br>$Q_{1-2} = \Delta U_{1-2} + A_{1-2} = \frac{3}{2}(p_2V_2 - p_1V_1) + 0 = \frac{3}{2}(2p_0V_0 - p_0V_0) = \frac{3}{2}p_0V_0$.</p><p><strong>4.</strong> Для изобарного процесса 2-3 работа газа $A_{2-3} = p_2(V_3 - V_2) = 2p_0(3V_0 - V_0) = 4p_0V_0$.<br>Изменение внутренней энергии $\Delta U_{2-3} = \frac{3}{2}(p_3V_3 - p_2V_2) = \frac{3}{2}(2p_0 \cdot 3V_0 - 2p_0 \cdot V_0) = \frac{3}{2}(6p_0V_0 - 2p_0V_0) = \frac{3}{2}(4p_0V_0) = 6p_0V_0$.<br>Тогда количество теплоты:<br>$Q_{2-3} = \Delta U_{2-3} + A_{2-3} = 6p_0V_0 + 4p_0V_0 = 10p_0V_0$.</p><p><strong>5.</strong> Суммарное количество теплоты, полученное от нагревателя:<br>$Q_{нагр} = Q_{1-2} + Q_{2-3} = \frac{3}{2}p_0V_0 + 10p_0V_0 = (\frac{3}{2} + \frac{20}{2})p_0V_0 = \frac{23}{2}p_0V_0$.</p><p><strong>6.</strong> Наконец, вычисляем КПД цикла:<br>$\eta = \frac{A'}{Q_{нагр}} = \frac{2p_0V_0}{\frac{23}{2}p_0V_0} = \frac{2 \cdot 2}{23} = \frac{4}{23}$.<br>Выразим результат в процентах:<br>$\eta = \frac{4}{23} \cdot 100\% \approx 17.39\% \approx 17\%$.</p><p><strong>Ответ:</strong> $\eta = \frac{4}{23} \approx 17\%$.</p>"
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            "text" => "<p><strong>Дано:</strong><br>Циклический процесс 1-2-3-4-1.<br>Рабочее тело - одноатомный идеальный газ.<br>Параметры состояний в узловых точках цикла (согласно графику):<br>Точка 1: $p_1 = p_0$, $V_1 = V_0$.<br>Точка 2: $p_2 = 2p_0$, $V_2 = V_0$.<br>Точка 3: $p_3 = 2p_0$, $V_3 = 3V_0$.<br>Точка 4: $p_4 = p_0$, $V_4 = 3V_0$.</p><p><strong>Найти:</strong><br>КПД цикла $\eta$.</p><p><strong>Решение:</strong><br>Коэффициент полезного действия (КПД) теплового двигателя определяется как отношение полезной работы $A'$, совершенной газом за цикл, к количеству теплоты $Q_{нагр}$, полученному от нагревателя:<br>$\eta = \frac{A'}{Q_{нагр}}$</p><p><strong>1.</strong> Полезная работа $A'$ за цикл численно равна площади фигуры, ограниченной графиком цикла на диаграмме в координатах p-V. В данном случае фигура является прямоугольником.<br>$A' = (p_2 - p_1) \cdot (V_3 - V_2) = (2p_0 - p_0) \cdot (3V_0 - V_0) = p_0 \cdot 2V_0 = 2p_0V_0$.</p><p><strong>2.</strong> Количество теплоты $Q_{нагр}$ газ получает на тех участках цикла, где его температура увеличивается. Согласно уравнению состояния идеального газа $pV = \nu RT$, температура растет при увеличении произведения $pV$.<br>- Участок 1-2 (изохорное нагревание): объем постоянен ($V=V_0$), давление растет от $p_0$ до $2p_0$. Произведение $pV$ увеличивается, следовательно, газ получает теплоту $Q_{1-2}$.<br>- Участок 2-3 (изобарное расширение): давление постоянно ($p=2p_0$), объем растет от $V_0$ до $3V_0$. Произведение $pV$ увеличивается, следовательно, газ получает теплоту $Q_{2-3}$.<br>- На участках 3-4 и 4-1 произведение $pV$ уменьшается, значит, температура падает, и газ отдает теплоту холодильнику.<br>Таким образом, общее количество теплоты, полученное от нагревателя, равно:<br>$Q_{нагр} = Q_{1-2} + Q_{2-3}$.</p><p><strong>3.</strong> Рассчитаем количество теплоты для каждого участка по первому началу термодинамики: $Q = \Delta U + A$. Для одноатомного идеального газа изменение внутренней энергии равно $\Delta U = \frac{3}{2}\nu R \Delta T = \frac{3}{2}\Delta(pV)$.<br>Для изохорного процесса 1-2 работа $A_{1-2}=0$.<br>$Q_{1-2} = \Delta U_{1-2} + A_{1-2} = \frac{3}{2}(p_2V_2 - p_1V_1) + 0 = \frac{3}{2}(2p_0V_0 - p_0V_0) = \frac{3}{2}p_0V_0$.</p><p><strong>4.</strong> Для изобарного процесса 2-3 работа газа $A_{2-3} = p_2(V_3 - V_2) = 2p_0(3V_0 - V_0) = 4p_0V_0$.<br>Изменение внутренней энергии $\Delta U_{2-3} = \frac{3}{2}(p_3V_3 - p_2V_2) = \frac{3}{2}(2p_0 \cdot 3V_0 - 2p_0 \cdot V_0) = \frac{3}{2}(6p_0V_0 - 2p_0V_0) = \frac{3}{2}(4p_0V_0) = 6p_0V_0$.<br>Тогда количество теплоты:<br>$Q_{2-3} = \Delta U_{2-3} + A_{2-3} = 6p_0V_0 + 4p_0V_0 = 10p_0V_0$.</p><p><strong>5.</strong> Суммарное количество теплоты, полученное от нагревателя:<br>$Q_{нагр} = Q_{1-2} + Q_{2-3} = \frac{3}{2}p_0V_0 + 10p_0V_0 = (\frac{3}{2} + \frac{20}{2})p_0V_0 = \frac{23}{2}p_0V_0$.</p><p><strong>6.</strong> Наконец, вычисляем КПД цикла:<br>$\eta = \frac{A'}{Q_{нагр}} = \frac{2p_0V_0}{\frac{23}{2}p_0V_0} = \frac{2 \cdot 2}{23} = \frac{4}{23}$.<br>Выразим результат в процентах:<br>$\eta = \frac{4}{23} \cdot 100\% \approx 17.39\% \approx 17\%$.</p><p><strong>Ответ:</strong> $\eta = \frac{4}{23} \approx 17\%$.</p>"
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№18.3 (с. 134)
Условие. №18.3 (с. 134)
скриншот условия
Физика, 10-11 класс Задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2008, красного цвета, страница 134, номер 18.3, Условие
Физика, 10-11 класс Задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2008, красного цвета, страница 134, номер 18.3, Условие (продолжение 2)

18.3. На рисунке показан цикл из двух изохор и двух изобар. Найдите КПД цикла, если рабочее тело — одноатомный идеальный газ.

☑ 17 %.

Решение. КПД цикла $ \eta = A'/Q $. Совершенная за цикл работа $A'$ численно равна площади прямоугольника: $ A' = 2p_0V_0 $. Полученное за цикл от нагревателя количество теплоты $ Q = Q_{1-2} + Q_{2-3} $. Из уравнения Клапейрона получаем $ T_2 = 2T_1 $, $ T_3 = 6T_1 $. Используя результаты решения задачи 17.6, находим:

$ Q_{1-2} = \nu C_V(T_2 - T_1) = 3\nu RT_1/2 $, $ Q_{2-3} = \nu C_p(T_3 - T_2) = 10\nu RT_1 $.

Здесь $ \nu $ — количество вещества. Подставляя полученные значения в формулу для КПД и используя соотношение $ p_0V_0 = \nu RT_1 $, получаем $ \eta = 4/23 \approx 0,17 $.

Решение. №18.3 (с. 134)

Дано:
Циклический процесс 1-2-3-4-1.
Рабочее тело - одноатомный идеальный газ.
Параметры состояний в узловых точках цикла (согласно графику):
Точка 1: $p_1 = p_0$, $V_1 = V_0$.
Точка 2: $p_2 = 2p_0$, $V_2 = V_0$.
Точка 3: $p_3 = 2p_0$, $V_3 = 3V_0$.
Точка 4: $p_4 = p_0$, $V_4 = 3V_0$.

Найти:
КПД цикла $\eta$.

Решение:
Коэффициент полезного действия (КПД) теплового двигателя определяется как отношение полезной работы $A'$, совершенной газом за цикл, к количеству теплоты $Q_{нагр}$, полученному от нагревателя:
$\eta = \frac{A'}{Q_{нагр}}$

1. Полезная работа $A'$ за цикл численно равна площади фигуры, ограниченной графиком цикла на диаграмме в координатах p-V. В данном случае фигура является прямоугольником.
$A' = (p_2 - p_1) \cdot (V_3 - V_2) = (2p_0 - p_0) \cdot (3V_0 - V_0) = p_0 \cdot 2V_0 = 2p_0V_0$.

2. Количество теплоты $Q_{нагр}$ газ получает на тех участках цикла, где его температура увеличивается. Согласно уравнению состояния идеального газа $pV = \nu RT$, температура растет при увеличении произведения $pV$.
- Участок 1-2 (изохорное нагревание): объем постоянен ($V=V_0$), давление растет от $p_0$ до $2p_0$. Произведение $pV$ увеличивается, следовательно, газ получает теплоту $Q_{1-2}$.
- Участок 2-3 (изобарное расширение): давление постоянно ($p=2p_0$), объем растет от $V_0$ до $3V_0$. Произведение $pV$ увеличивается, следовательно, газ получает теплоту $Q_{2-3}$.
- На участках 3-4 и 4-1 произведение $pV$ уменьшается, значит, температура падает, и газ отдает теплоту холодильнику.
Таким образом, общее количество теплоты, полученное от нагревателя, равно:
$Q_{нагр} = Q_{1-2} + Q_{2-3}$.

3. Рассчитаем количество теплоты для каждого участка по первому началу термодинамики: $Q = \Delta U + A$. Для одноатомного идеального газа изменение внутренней энергии равно $\Delta U = \frac{3}{2}\nu R \Delta T = \frac{3}{2}\Delta(pV)$.
Для изохорного процесса 1-2 работа $A_{1-2}=0$.
$Q_{1-2} = \Delta U_{1-2} + A_{1-2} = \frac{3}{2}(p_2V_2 - p_1V_1) + 0 = \frac{3}{2}(2p_0V_0 - p_0V_0) = \frac{3}{2}p_0V_0$.

4. Для изобарного процесса 2-3 работа газа $A_{2-3} = p_2(V_3 - V_2) = 2p_0(3V_0 - V_0) = 4p_0V_0$.
Изменение внутренней энергии $\Delta U_{2-3} = \frac{3}{2}(p_3V_3 - p_2V_2) = \frac{3}{2}(2p_0 \cdot 3V_0 - 2p_0 \cdot V_0) = \frac{3}{2}(6p_0V_0 - 2p_0V_0) = \frac{3}{2}(4p_0V_0) = 6p_0V_0$.
Тогда количество теплоты:
$Q_{2-3} = \Delta U_{2-3} + A_{2-3} = 6p_0V_0 + 4p_0V_0 = 10p_0V_0$.

5. Суммарное количество теплоты, полученное от нагревателя:
$Q_{нагр} = Q_{1-2} + Q_{2-3} = \frac{3}{2}p_0V_0 + 10p_0V_0 = (\frac{3}{2} + \frac{20}{2})p_0V_0 = \frac{23}{2}p_0V_0$.

6. Наконец, вычисляем КПД цикла:
$\eta = \frac{A'}{Q_{нагр}} = \frac{2p_0V_0}{\frac{23}{2}p_0V_0} = \frac{2 \cdot 2}{23} = \frac{4}{23}$.
Выразим результат в процентах:
$\eta = \frac{4}{23} \cdot 100\% \approx 17.39\% \approx 17\%$.

Ответ: $\eta = \frac{4}{23} \approx 17\%$.

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Мы подготовили для вас ответ c подробным объяснением домашего задания по физике за 10-11 класс, для упражнения номер 18.3 расположенного на странице 134 к задачнику 2008 года издания для учащихся школ и гимназий.

Теперь на нашем сайте ГДЗ.ТОП вы всегда легко и бесплатно найдёте условие с правильным ответом на вопрос «Как решить ДЗ» и «Как сделать» задание по физике к упражнению №18.3 (с. 134), авторов: Гельфгат (Илья Маркович), Генденштейн (Лев Элевич), Кирик (Леонид Анатольевич), профильный уровень обучения учебного пособия издательства Илекса.