Номер 5, страница 146 - гдз по физике 9 класс учебник Шахмаев, Бунчук

Физика, 9 класс Учебник, авторы: Шахмаев Николай Михайлович, Бунчук Алексей Васильевич, издательство Мнемозина, Москва, 2007, голубого цвета

Авторы: Шахмаев Н. М., Бунчук А. В.

Тип: Учебник

Издательство: Мнемозина

Год издания: 2007 - 2026

Цвет обложки: голубой

ISBN: 978-5-346-01799-8

Глава 8. Закон сохранения энергии. Параграф 33. Коэффициент полезного действия - номер 5, страница 146.

App\Models\Task {#1030 // resources/views/models/task/default.blade.php
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                              "field_accusative_case" => "физику"
                              "field_creative_case" => "физикой"
                              "field_dative_case" => "физике"
                              "field_genitive_case" => "физики"
                              "field_nominative_case" => "физика"
                              "field_prepositional_case" => "физике"
                            ]
                            "field_foreign_lang_name" => null
                            "field_short_name" => null
                            "field_subject_type" => "technical_subject"
                            "field_translit" => "fizika"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1122
                      #items: array:1 [
                        0 => App\Models\Term {#1123
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 5458
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "9"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "девятый"
                              "field_creative_case" => "девятым"
                              "field_dative_case" => "девятому"
                              "field_genitive_case" => "девятого"
                              "field_nominative_case" => "девятый"
                              "field_prepositional_case" => "девятом"
                            ]
                            "field_translit" => "devjatyj"
                          ]
                          #original: array:6 [
                            "id" => 5458
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "9"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "девятый"
                              "field_creative_case" => "девятым"
                              "field_dative_case" => "девятому"
                              "field_genitive_case" => "девятого"
                              "field_nominative_case" => "девятый"
                              "field_prepositional_case" => "девятом"
                            ]
                            "field_translit" => "devjatyj"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1124
                      #items: array:1 [
                        0 => App\Models\Term {#1125
                          #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" => 5155
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Мнемозина"
                            "field_cases" => null
                            "field_translit" => "mnemozina"
                          ]
                          #original: array:6 [
                            "id" => 5155
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Мнемозина"
                            "field_cases" => null
                            "field_translit" => "mnemozina"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1126
                      #items: array:2 [
                        0 => App\Models\Term {#1127
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 6294
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Шахмаев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Николай"
                            "field_patronymic" => "Михайлович"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 6294
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Шахмаев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Николай"
                            "field_patronymic" => "Михайлович"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        1 => App\Models\Term {#1128
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 3942
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Бунчук"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Алексей"
                            "field_patronymic" => "Васильевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 3942
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Бунчук"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Алексей"
                            "field_patronymic" => "Васильевич"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1129
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1130
                      #items: array:1 [
                        0 => App\Models\Term {#1131
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [
                            "id" => 6671
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "учебник"
                              "field_creative_case" => "учебником"
                              "field_dative_case" => "учебнику"
                              "field_genitive_case" => "учебника"
                              "field_nominative_case" => "учебник"
                              "field_prepositional_case" => "учебнике"
                            ]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik"
                          ]
                          #original: array:10 [
                            "id" => 6671
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [
                              "field_accusative_case" => "учебник"
                              "field_creative_case" => "учебником"
                              "field_dative_case" => "учебнику"
                              "field_genitive_case" => "учебника"
                              "field_nominative_case" => "учебник"
                              "field_prepositional_case" => "учебнике"
                            ]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1132
                      #items: array:1 [
                        0 => App\Models\Term {#1133
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [
                              "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 {#1134
                      #items: array:1 [
                        0 => App\Models\Term {#1135
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [
                              "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 {#1136
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1137
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1138
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1139
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => "4"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1140
                      #items: array:1 [
                        0 => App\Models\Term {#1141
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 33
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
                            "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" => "stereotipnoe"
                          ]
                          #original: array:6 [
                            "id" => 33
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
                            "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" => "stereotipnoe"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1142
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2007"
                    "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" => "362"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/shahmaev-u/"
                    "field_isbn" => "978-5-346-01799-8"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_09/shahmaev-u/covers/cover1.webp?ts=1759080267"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/shahmaev-u/covers/cover1.webp?ts=1759080267"
                        "alt" => ""
                        "width" => "2294"
                        "height" => "3039"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1143
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1144
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1145
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/9-klass/fizika/shahmaev-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1146
                      #items: array:1 [
                        0 => App\Models\Term {#1147
                          #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" => 52
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "голубой"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "голубой"
                              "field_creative_case" => "голубым"
                              "field_dative_case" => "голубому"
                              "field_genitive_case" => "голубого"
                              "field_nominative_case" => "голубой"
                              "field_prepositional_case" => "голубом"
                            ]
                            "field_translit" => "goluboy"
                          ]
                          #original: array:6 [
                            "id" => 52
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "голубой"
                            "field_cases" => array:6 [
                              "field_accusative_case" => "голубой"
                              "field_creative_case" => "голубым"
                              "field_dative_case" => "голубому"
                              "field_genitive_case" => "голубого"
                              "field_nominative_case" => "голубой"
                              "field_prepositional_case" => "голубом"
                            ]
                            "field_translit" => "goluboy"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
                  #original: array:50 [
                    "id" => 2906
                    "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 {#1121}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1122}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1124}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1126}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1129}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1130}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1132}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1134}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1136}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1137}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1138}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1139}
                    "field_publication_number" => "4"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1140}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1142}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2007"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
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                    "field_link_to_source" => null
                    "field_tasks_count" => "362"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/shahmaev-u/"
                    "field_isbn" => "978-5-346-01799-8"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_09/shahmaev-u/covers/cover1.webp?ts=1759080267"
                    ]
                    "field_cover_alts" => array:1 [
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                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/shahmaev-u/covers/cover1.webp?ts=1759080267"
                        "alt" => ""
                        "width" => "2294"
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                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1143}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1144}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1145}
                    "field_url" => "/9-klass/fizika/shahmaev-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1146}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1148
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1436826
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Закон сохранения энергии"
            "field_branch_order" => "8"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1120}
            "field_page_start" => "119"
            "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 {#1150}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1148}
          ]
          #changes: []
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          #dateFormat: null
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          #hidden: []
          #visible: []
          #fillable: []
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            0 => "*"
          ]
        }
        1 => App\Models\Branch {#1149
          #connection: "mysql"
          #table: "branches"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
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          #attributes: array:24 [
            "id" => 1436832
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Коэффициент полезного действия"
            "field_branch_order" => "33"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1154
              #items: array:1 [
                0 => App\Models\Term {#1151
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
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                  #perPage: 15
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                  #escapeWhenCastingToString: false
                  #attributes: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Параграф"
                      "field_creative_case" => "Параграфом"
                      "field_dative_case" => "Параграфу"
                      "field_genitive_case" => "Параграфа"
                      "field_nominative_case" => "Параграф"
                      "field_prepositional_case" => "Параграфе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #original: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [
                      "field_accusative_case" => "Параграф"
                      "field_creative_case" => "Параграфом"
                      "field_dative_case" => "Параграфу"
                      "field_genitive_case" => "Параграфа"
                      "field_nominative_case" => "Параграф"
                      "field_prepositional_case" => "Параграфе"
                    ]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #changes: []
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                  #attributeCastCache: []
                  #dateFormat: null
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                  +timestamps: true
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                  #hidden: []
                  #visible: []
                  #fillable: []
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "144"
            "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 {#1153
              #items: array:1 [
                0 => App\Models\Book {#1119}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1152
              #items: array:1 [
                0 => App\Models\Branch {#1034}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1436832
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Коэффициент полезного действия"
            "field_branch_order" => "33"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1154}
            "field_page_start" => "144"
            "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 {#1153}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1152}
          ]
          #changes: []
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          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
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          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
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          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1099
      #items: array:2 [
        0 => App\Models\Element {#1092
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:7 [
            "id" => 1702504
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1081
              #items: array:1 [
                0 => App\Models\Edition {#1089
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 6109
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1087
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "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 {#1088
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1086
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1083
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6109
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1087}
                    "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 {#1088}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1086}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1083}
                    "field_content_source" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1437083"
              "type" => "task"
            ]
            "text" => "<p><strong>*5.</strong> На коротком плече рычага подвешен груз массой $100 \text{ кг}$. Для его подъема к длинному плечу приложили силу $250 \text{ Н}$. Преодолевая трение, груз равномерно подняли на высоту $0,08 \text{ м}$, при этом точка приложения силы опустилась на $0,4 \text{ м}$. Определите КПД рычага.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "5-1.jpg"
                "alt" => null
                "width" => "1602"
                "height" => 298
                "path" => "/media/fizika_09/shahmaev-u/0-33/5-1.webp?ts=1759448860"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1702504
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1081}
            "task" => array:2 [
              "refs" => "1437083"
              "type" => "task"
            ]
            "text" => "<p><strong>*5.</strong> На коротком плече рычага подвешен груз массой $100 \text{ кг}$. Для его подъема к длинному плечу приложили силу $250 \text{ Н}$. Преодолевая трение, груз равномерно подняли на высоту $0,08 \text{ м}$, при этом точка приложения силы опустилась на $0,4 \text{ м}$. Определите КПД рычага.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "5-1.jpg"
                "alt" => null
                "width" => "1602"
                "height" => 298
                "path" => "/media/fizika_09/shahmaev-u/0-33/5-1.webp?ts=1759448860"
              ]
            ]
          ]
          #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\Element {#1085
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:6 [
            "id" => 1732425
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1107
              #items: array:1 [
                0 => App\Models\Edition {#1084
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 6315
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1079
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1080
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1077
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1078
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6315
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1079}
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1080}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1077}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1078}
                    "field_content_source" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1437083"
              "type" => "task"
            ]
            "text" => "<p><strong>Дано:</strong></p><p>Масса груза, $m = 100$ кг<br>Приложенная сила, $F = 250$ Н<br>Высота подъема груза, $h_1 = 0,08$ м<br>Перемещение точки приложения силы, $h_2 = 0,4$ м<br>Ускорение свободного падения, $g \approx 10 \frac{\text{Н}}{\text{кг}}$</p><p><strong>Найти:</strong></p><p>КПД рычага, $\eta$ - ?</p><p><strong>Решение:</strong></p><p>Коэффициент полезного действия (КПД) механизма определяется как отношение полезной работы к полной (затраченной) работе, выраженное в процентах.</p><p>Формула для расчета КПД:</p><p>$\eta = \frac{A_{полезн}}{A_{затрач}} \cdot 100\%$</p><p><strong>1.</strong> Найдем полезную работу ($A_{полезн}$). Полезная работа — это работа по подъему груза на высоту $h_1$. Она равна произведению веса груза $\text{P}$ на высоту подъема $h_1$. Вес груза вычисляется по формуле $P = m \cdot g$.</p><p>$A_{полезн} = P \cdot h_1 = m \cdot g \cdot h_1$</p><p>Подставим числовые значения:</p><p>$A_{полезн} = 100 \text{ кг} \cdot 10 \frac{\text{Н}}{\text{кг}} \cdot 0,08 \text{ м} = 80 \text{ Дж}$</p><p><strong>2.</strong> Найдем затраченную работу ($A_{затрач}$). Затраченная работа — это работа, совершенная приложенной силой $\text{F}$ на пути $h_2$.</p><p>$A_{затрач} = F \cdot h_2$</p><p>Подставим числовые значения:</p><p>$A_{затрач} = 250 \text{ Н} \cdot 0,4 \text{ м} = 100 \text{ Дж}$</p><p><strong>3.</strong> Теперь можем рассчитать КПД рычага, подставив найденные значения работ в основную формулу:</p><p>$\eta = \frac{80 \text{ Дж}}{100 \text{ Дж}} \cdot 100\% = 0,8 \cdot 100\% = 80\%$</p><p><strong>Ответ:</strong> КПД рычага составляет 80%.</p>"
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            "text" => "<p><strong>Дано:</strong></p><p>Масса груза, $m = 100$ кг<br>Приложенная сила, $F = 250$ Н<br>Высота подъема груза, $h_1 = 0,08$ м<br>Перемещение точки приложения силы, $h_2 = 0,4$ м<br>Ускорение свободного падения, $g \approx 10 \frac{\text{Н}}{\text{кг}}$</p><p><strong>Найти:</strong></p><p>КПД рычага, $\eta$ - ?</p><p><strong>Решение:</strong></p><p>Коэффициент полезного действия (КПД) механизма определяется как отношение полезной работы к полной (затраченной) работе, выраженное в процентах.</p><p>Формула для расчета КПД:</p><p>$\eta = \frac{A_{полезн}}{A_{затрач}} \cdot 100\%$</p><p><strong>1.</strong> Найдем полезную работу ($A_{полезн}$). Полезная работа — это работа по подъему груза на высоту $h_1$. Она равна произведению веса груза $\text{P}$ на высоту подъема $h_1$. Вес груза вычисляется по формуле $P = m \cdot g$.</p><p>$A_{полезн} = P \cdot h_1 = m \cdot g \cdot h_1$</p><p>Подставим числовые значения:</p><p>$A_{полезн} = 100 \text{ кг} \cdot 10 \frac{\text{Н}}{\text{кг}} \cdot 0,08 \text{ м} = 80 \text{ Дж}$</p><p><strong>2.</strong> Найдем затраченную работу ($A_{затрач}$). Затраченная работа — это работа, совершенная приложенной силой $\text{F}$ на пути $h_2$.</p><p>$A_{затрач} = F \cdot h_2$</p><p>Подставим числовые значения:</p><p>$A_{затрач} = 250 \text{ Н} \cdot 0,4 \text{ м} = 100 \text{ Дж}$</p><p><strong>3.</strong> Теперь можем рассчитать КПД рычага, подставив найденные значения работ в основную формулу:</p><p>$\eta = \frac{80 \text{ Дж}}{100 \text{ Дж}} \cdot 100\% = 0,8 \cdot 100\% = 80\%$</p><p><strong>Ответ:</strong> КПД рычага составляет 80%.</p>"
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№5 (с. 146)
Условие. №5 (с. 146)
скриншот условия
Физика, 9 класс Учебник, авторы: Шахмаев Николай Михайлович, Бунчук Алексей Васильевич, издательство Мнемозина, Москва, 2007, голубого цвета, страница 146, номер 5, Условие

*5. На коротком плече рычага подвешен груз массой $100 \text{ кг}$. Для его подъема к длинному плечу приложили силу $250 \text{ Н}$. Преодолевая трение, груз равномерно подняли на высоту $0,08 \text{ м}$, при этом точка приложения силы опустилась на $0,4 \text{ м}$. Определите КПД рычага.

Решение. №5 (с. 146)

Дано:

Масса груза, $m = 100$ кг
Приложенная сила, $F = 250$ Н
Высота подъема груза, $h_1 = 0,08$ м
Перемещение точки приложения силы, $h_2 = 0,4$ м
Ускорение свободного падения, $g \approx 10 \frac{\text{Н}}{\text{кг}}$

Найти:

КПД рычага, $\eta$ - ?

Решение:

Коэффициент полезного действия (КПД) механизма определяется как отношение полезной работы к полной (затраченной) работе, выраженное в процентах.

Формула для расчета КПД:

$\eta = \frac{A_{полезн}}{A_{затрач}} \cdot 100\%$

1. Найдем полезную работу ($A_{полезн}$). Полезная работа — это работа по подъему груза на высоту $h_1$. Она равна произведению веса груза $\text{P}$ на высоту подъема $h_1$. Вес груза вычисляется по формуле $P = m \cdot g$.

$A_{полезн} = P \cdot h_1 = m \cdot g \cdot h_1$

Подставим числовые значения:

$A_{полезн} = 100 \text{ кг} \cdot 10 \frac{\text{Н}}{\text{кг}} \cdot 0,08 \text{ м} = 80 \text{ Дж}$

2. Найдем затраченную работу ($A_{затрач}$). Затраченная работа — это работа, совершенная приложенной силой $\text{F}$ на пути $h_2$.

$A_{затрач} = F \cdot h_2$

Подставим числовые значения:

$A_{затрач} = 250 \text{ Н} \cdot 0,4 \text{ м} = 100 \text{ Дж}$

3. Теперь можем рассчитать КПД рычага, подставив найденные значения работ в основную формулу:

$\eta = \frac{80 \text{ Дж}}{100 \text{ Дж}} \cdot 100\% = 0,8 \cdot 100\% = 80\%$

Ответ: КПД рычага составляет 80%.

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