Номер 3.1, страница 18 - гдз по физике 8-11 класс учебник, задачник Гельфгат, Генденштейн

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

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

Тип: Учебник, задачник

Издательство: Илекса

Год издания: 2005 - 2026

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

ISBN: 978-5-89237-332-6

Задачи. Механика. 3. Закон всемирного тяготения - номер 3.1, страница 18.

App\Models\Task {#1030 // resources/views/models/task/default.blade.php
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                            "field_translit" => "odinadcatyj"
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                            "id" => 5460
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "11"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "odinadcatyj"
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                      ]
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                    }
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1133
                      #items: array:1 [
                        0 => App\Models\Term {#1134
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
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                          #withCount: []
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                          #attributes: array:6 [
                            "id" => 5158
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_cases" => null
                            "field_translit" => "ileksa"
                          ]
                          #original: array:6 [
                            "id" => 5158
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Илекса"
                            "field_cases" => null
                            "field_translit" => "ileksa"
                          ]
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                        }
                      ]
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                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1135
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                        0 => App\Models\Term {#1136
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
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                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:12 [
                            "id" => 4102
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Гельфгат"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Илья"
                            "field_patronymic" => "Маркович"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4102
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Гельфгат"
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                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Илья"
                            "field_patronymic" => "Маркович"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
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                          #relations: []
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                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        1 => App\Models\Term {#1137
                          #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" => 4104
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Генденштейн"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Лев"
                            "field_patronymic" => "Элевич"
                            "field_surname_rp" => "Генденштейна"
                          ]
                          #original: array:12 [
                            "id" => 4104
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Генденштейн"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Лев"
                            "field_patronymic" => "Элевич"
                            "field_surname_rp" => "Генденштейна"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        2 => App\Models\Term {#1138
                          #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" => 4583
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Кирик"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Леонид"
                            "field_patronymic" => "Анатольевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4583
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Кирик"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Леонид"
                            "field_patronymic" => "Анатольевич"
                            "field_surname_rp" => null
                          ]
                          #changes: []
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                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
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                          #relations: []
                          #touches: []
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                          #hidden: []
                          #visible: []
                          #fillable: []
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                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1139
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_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: []
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                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:10 [
                            "id" => 6673
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник, задачник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik, zadachnik"
                          ]
                          #original: array:10 [
                            "id" => 6673
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Учебник, задачник"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "uchebnik, zadachnik"
                          ]
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                          #attributeCastCache: []
                          #dateFormat: null
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                          #dispatchesEvents: []
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                          #relations: []
                          #touches: []
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                          #hidden: []
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                          #fillable: []
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                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1142
                      #items: array:1 [
                        0 => App\Models\Term {#1143
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "rossiya"
                          ]
                          #original: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "rossiya"
                          ]
                          #changes: []
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                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
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                          #dispatchesEvents: []
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                          #relations: []
                          #touches: []
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                          #hidden: []
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                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1144
                      #items: array:1 [
                        0 => App\Models\Term {#1145
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "moskva"
                          ]
                          #original: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "moskva"
                          ]
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                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1146
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1147
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1148
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1149
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => "6"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1150
                      #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
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 35
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "исправленное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "ispravlennoe"
                          ]
                          #original: array:6 [
                            "id" => 35
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "исправленное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "ispravlennoe"
                          ]
                          #changes: []
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                          ]
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                      ]
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                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1152
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
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                    "field_publication_year" => "2005"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
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                    "field_link_to_source" => null
                    "field_tasks_count" => "1001"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_08/gelfgat-u/"
                    "field_isbn" => "978-5-89237-332-6"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                        "alt" => ""
                        "width" => "1813"
                        "height" => "2441"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1153
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1154
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1155
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/8-klass/fizika/ileksa-gelfgat-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1156
                      #items: array:1 [
                        0 => App\Models\Term {#1157
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
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                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "siniy"
                          ]
                          #original: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "siniy"
                          ]
                          #changes: []
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                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
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                          #relations: []
                          #touches: []
                          +timestamps: true
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                          #hidden: []
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                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 379
                      "subject" => 556
                      "class_subject" => 492
                    ]
                  ]
                  #original: array:50 [
                    "id" => 5401
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1127}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1128}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1133}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1135}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1139}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1140}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1142}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1144}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1146}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1147}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1148}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1149}
                    "field_publication_number" => "6"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1150}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1152}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "мужчина в красном, летит на черном шаре"
                    "field_publication_year" => "2005"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1001"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_08/gelfgat-u/"
                    "field_isbn" => "978-5-89237-332-6"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                        "alt" => ""
                        "width" => "1813"
                        "height" => "2441"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1153}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1154}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1155}
                    "field_url" => "/8-klass/fizika/ileksa-gelfgat-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1156}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 379
                      "subject" => 556
                      "class_subject" => 492
                    ]
                  ]
                  #changes: []
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                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1158
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1287866
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Задачи"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1124}
            "field_page_start" => "5"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1160}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1158}
          ]
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          #touches: []
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          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Branch {#1159
          #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" => 1287867
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Механика"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1161
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "5"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
            "field_display_task_interval" => "0"
            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1162
              #items: array:1 [
                0 => App\Models\Book {#1125}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1163
              #items: array:1 [
                0 => App\Models\Branch {#1034}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1287867
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Механика"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1161}
            "field_page_start" => "5"
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            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
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            "field_metatags_description" => null
            "field_h1" => null
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1162}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1163}
          ]
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          #dateFormat: null
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          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1164
          #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" => 1287870
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "3. Закон всемирного тяготения"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1165
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "18"
            "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
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            "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 {#1166
              #items: array:1 [
                0 => App\Models\Book {#1125}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1175
              #items: array:1 [
                0 => App\Models\Branch {#1174
                  #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" => 1287867
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_display_title" => "Механика"
                    "field_branch_order" => null
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1176 …2}
                    "field_page_start" => "5"
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                    "field_branch_title_in_content" => "0"
                    "field_navigation_title" => null
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                    "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 {#1177 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1178 …2}
                  ]
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                    "id" => 1287867
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                    "field_branch_order" => null
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1176 …2}
                    "field_page_start" => "5"
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                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1177 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1178 …2}
                  ]
                  #changes: []
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                  #attributeCastCache: []
                  #dateFormat: null
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                  #dispatchesEvents: []
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                  #touches: []
                  +timestamps: true
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                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1287870
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "3. Закон всемирного тяготения"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1165}
            "field_page_start" => "18"
            "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 {#1166}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1175}
          ]
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          #dateFormat: null
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          +timestamps: true
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          #visible: []
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          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1111
      #items: array:3 [
        0 => App\Models\Element {#1103
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
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          #perPage: 15
          +exists: true
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          #escapeWhenCastingToString: false
          #attributes: array:7 [
            "id" => 1477775
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1096
              #items: array:1 [
                0 => App\Models\Edition {#1104
                  #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" => 5410
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1101 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1100 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1099 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1097 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 5410
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1101 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
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                    "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 {#1100 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1099 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1097 …2}
                    "field_content_source" => null
                  ]
                  #changes: []
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                  #attributeCastCache: []
                  #dateFormat: null
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                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1288000"
              "type" => "task"
            ]
            "text" => "<p><strong>3.1.</strong> Оцените массу Солнца, считая расстояние $\text{R}$ от Земли до Солнца равным $1,5 \cdot 10^8$ км.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "1-1.jpg"
                "alt" => null
                "width" => "1423"
                "height" => 183
                "path" => "/media/fizika_08/gelfgat-u/0-03/1-1.webp?ts=1756049683"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1477775
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1096}
            "task" => array:2 [
              "refs" => "1288000"
              "type" => "task"
            ]
            "text" => "<p><strong>3.1.</strong> Оцените массу Солнца, считая расстояние $\text{R}$ от Земли до Солнца равным $1,5 \cdot 10^8$ км.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "1-1.jpg"
                "alt" => null
                "width" => "1423"
                "height" => 183
                "path" => "/media/fizika_08/gelfgat-u/0-03/1-1.webp?ts=1756049683"
              ]
            ]
          ]
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          #attributeCastCache: []
          #dateFormat: null
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          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Element {#1098
          #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" => 1478140
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1086
              #items: array:1 [
                0 => App\Models\Edition {#1095
                  #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" => 5411
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1094 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "image"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1092 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1088 …2}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1091 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 5411
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1094 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "image"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1092 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1088 …2}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1091 …2}
                    "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" => "1288000"
              "type" => "task"
            ]
            "img" => array:1 [
              0 => array:5 [
                "name" => "1-1.jpg"
                "alt" => null
                "width" => "1439"
                "height" => 211
                "path" => "/media/fizika_08/gelfgat-u/1-03/1-1.webp?ts=1756049746"
              ]
            ]
          ]
          #original: array:6 [
            "id" => 1478140
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1086}
            "task" => array:2 [
              "refs" => "1288000"
              "type" => "task"
            ]
            "img" => array:1 [
              0 => array:5 [
                "name" => "1-1.jpg"
                "alt" => null
                "width" => "1439"
                "height" => 211
                "path" => "/media/fizika_08/gelfgat-u/1-03/1-1.webp?ts=1756049746"
              ]
            ]
          ]
          #changes: []
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          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Element {#1090
          #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" => 1737693
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1080
              #items: array:1 [
                0 => App\Models\Edition {#1089
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
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            "text" => "<p><strong>Дано:</strong></p><p>Расстояние от Земли до Солнца $R = 1,5 \cdot 10^8$ км.</p><p>Для решения задачи также потребуются справочные данные:</p><p>Гравитационная постоянная $G \approx 6,67 \cdot 10^{-11} \frac{Н \cdot м^2}{кг^2}$.</p><p>Период обращения Земли вокруг Солнца $T = 1$ год.</p><p><em>Перевод в систему СИ:</em><br>$R = 1,5 \cdot 10^8 \text{ км} = 1,5 \cdot 10^8 \cdot 10^3 \text{ м} = 1,5 \cdot 10^{11} \text{ м}$.<br>$T = 1 \text{ год} \approx 365,25 \text{ суток} = 365,25 \cdot 24 \cdot 3600 \text{ с} \approx 3,156 \cdot 10^7 \text{ с}$. Для оценки можно принять $T \approx 3,15 \cdot 10^7 \text{ с}$.</p><p><strong>Найти:</strong></p><p>Массу Солнца $M_С$.</p><p><strong>Решение:</strong></p><p>Будем считать, что Земля движется вокруг Солнца по круговой орбите. В этом случае движение Земли происходит под действием силы всемирного тяготения со стороны Солнца, которая сообщает Земле центростремительное ускорение.</p><p>Согласно второму закону Ньютона, сила, действующая на Землю, равна произведению массы Земли $m_З$ на ее центростремительное ускорение $a_ц$:</p><p>$F = m_З \cdot a_ц$</p><p>Силой, удерживающей Землю на орбите, является гравитационная сила:</p><p>$F_г = G \frac{M_С m_З}{R^2}$</p><p>Центростремительное ускорение тела, движущегося по окружности радиуса $\text{R}$ со скоростью $\text{v}$, равно:</p><p>$a_ц = \frac{v^2}{R}$</p><p>Приравниваем гравитационную силу и силу, вызывающую центростремительное движение:</p><p>$G \frac{M_С m_З}{R^2} = m_З \frac{v^2}{R}$</p><p>Масса Земли $m_З$ сокращается:</p><p>$G \frac{M_С}{R} = v^2$</p><p>Скорость движения Земли по орбите $\text{v}$ можно выразить через период обращения $\text{T}$ и радиус орбиты $\text{R}$. За время $\text{T}$ Земля проходит путь, равный длине окружности $2\pi R$:</p><p>$v = \frac{2\pi R}{T}$</p><p>Подставим выражение для скорости в предыдущую формулу:</p><p>$G \frac{M_С}{R} = \left(\frac{2\pi R}{T}\right)^2 = \frac{4\pi^2 R^2}{T^2}$</p><p>Выразим массу Солнца $M_С$:</p><p>$M_С = \frac{4\pi^2 R^3}{G T^2}$</p><p>Теперь подставим числовые значения в систему СИ и произведем вычисления, приняв $\pi \approx 3,14$:</p><p>$M_С = \frac{4 \cdot (3,14)^2 \cdot (1,5 \cdot 10^{11} \text{ м})^3}{6,67 \cdot 10^{-11} \frac{\text{Н} \cdot \text{м}^2}{\text{кг}^2} \cdot (3,15 \cdot 10^7 \text{ с})^2}$</p><p>$M_С = \frac{4 \cdot 9,86 \cdot 3,375 \cdot 10^{33}}{6,67 \cdot 10^{-11} \cdot 9,9225 \cdot 10^{14}} \text{ кг}$</p><p>$M_С \approx \frac{133,11 \cdot 10^{33}}{66,18 \cdot 10^3} \text{ кг} \approx \frac{1,33 \cdot 10^{35}}{6,62 \cdot 10^4} \text{ кг} \approx 2,01 \cdot 10^{30} \text{ кг}$</p><p>Округляя, получаем оценочное значение массы Солнца.</p><p><strong>Ответ:</strong> Масса Солнца составляет примерно $2 \cdot 10^{30}$ кг.</p>"
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            "text" => "<p><strong>Дано:</strong></p><p>Расстояние от Земли до Солнца $R = 1,5 \cdot 10^8$ км.</p><p>Для решения задачи также потребуются справочные данные:</p><p>Гравитационная постоянная $G \approx 6,67 \cdot 10^{-11} \frac{Н \cdot м^2}{кг^2}$.</p><p>Период обращения Земли вокруг Солнца $T = 1$ год.</p><p><em>Перевод в систему СИ:</em><br>$R = 1,5 \cdot 10^8 \text{ км} = 1,5 \cdot 10^8 \cdot 10^3 \text{ м} = 1,5 \cdot 10^{11} \text{ м}$.<br>$T = 1 \text{ год} \approx 365,25 \text{ суток} = 365,25 \cdot 24 \cdot 3600 \text{ с} \approx 3,156 \cdot 10^7 \text{ с}$. Для оценки можно принять $T \approx 3,15 \cdot 10^7 \text{ с}$.</p><p><strong>Найти:</strong></p><p>Массу Солнца $M_С$.</p><p><strong>Решение:</strong></p><p>Будем считать, что Земля движется вокруг Солнца по круговой орбите. В этом случае движение Земли происходит под действием силы всемирного тяготения со стороны Солнца, которая сообщает Земле центростремительное ускорение.</p><p>Согласно второму закону Ньютона, сила, действующая на Землю, равна произведению массы Земли $m_З$ на ее центростремительное ускорение $a_ц$:</p><p>$F = m_З \cdot a_ц$</p><p>Силой, удерживающей Землю на орбите, является гравитационная сила:</p><p>$F_г = G \frac{M_С m_З}{R^2}$</p><p>Центростремительное ускорение тела, движущегося по окружности радиуса $\text{R}$ со скоростью $\text{v}$, равно:</p><p>$a_ц = \frac{v^2}{R}$</p><p>Приравниваем гравитационную силу и силу, вызывающую центростремительное движение:</p><p>$G \frac{M_С m_З}{R^2} = m_З \frac{v^2}{R}$</p><p>Масса Земли $m_З$ сокращается:</p><p>$G \frac{M_С}{R} = v^2$</p><p>Скорость движения Земли по орбите $\text{v}$ можно выразить через период обращения $\text{T}$ и радиус орбиты $\text{R}$. За время $\text{T}$ Земля проходит путь, равный длине окружности $2\pi R$:</p><p>$v = \frac{2\pi R}{T}$</p><p>Подставим выражение для скорости в предыдущую формулу:</p><p>$G \frac{M_С}{R} = \left(\frac{2\pi R}{T}\right)^2 = \frac{4\pi^2 R^2}{T^2}$</p><p>Выразим массу Солнца $M_С$:</p><p>$M_С = \frac{4\pi^2 R^3}{G T^2}$</p><p>Теперь подставим числовые значения в систему СИ и произведем вычисления, приняв $\pi \approx 3,14$:</p><p>$M_С = \frac{4 \cdot (3,14)^2 \cdot (1,5 \cdot 10^{11} \text{ м})^3}{6,67 \cdot 10^{-11} \frac{\text{Н} \cdot \text{м}^2}{\text{кг}^2} \cdot (3,15 \cdot 10^7 \text{ с})^2}$</p><p>$M_С = \frac{4 \cdot 9,86 \cdot 3,375 \cdot 10^{33}}{6,67 \cdot 10^{-11} \cdot 9,9225 \cdot 10^{14}} \text{ кг}$</p><p>$M_С \approx \frac{133,11 \cdot 10^{33}}{66,18 \cdot 10^3} \text{ кг} \approx \frac{1,33 \cdot 10^{35}}{6,62 \cdot 10^4} \text{ кг} \approx 2,01 \cdot 10^{30} \text{ кг}$</p><p>Округляя, получаем оценочное значение массы Солнца.</p><p><strong>Ответ:</strong> Масса Солнца составляет примерно $2 \cdot 10^{30}$ кг.</p>"
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№3.1 (с. 18)
Условие. №3.1 (с. 18)
скриншот условия
Физика, 8-11 класс Учебник, задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2005, страница 18, номер 3.1, Условие

3.1. Оцените массу Солнца, считая расстояние $\text{R}$ от Земли до Солнца равным $1,5 \cdot 10^8$ км.

Решение. №3.1 (с. 18)
Физика, 8-11 класс Учебник, задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2005, страница 18, номер 3.1, Решение
Решение 2. №3.1 (с. 18)

Дано:

Расстояние от Земли до Солнца $R = 1,5 \cdot 10^8$ км.

Для решения задачи также потребуются справочные данные:

Гравитационная постоянная $G \approx 6,67 \cdot 10^{-11} \frac{Н \cdot м^2}{кг^2}$.

Период обращения Земли вокруг Солнца $T = 1$ год.

Перевод в систему СИ:
$R = 1,5 \cdot 10^8 \text{ км} = 1,5 \cdot 10^8 \cdot 10^3 \text{ м} = 1,5 \cdot 10^{11} \text{ м}$.
$T = 1 \text{ год} \approx 365,25 \text{ суток} = 365,25 \cdot 24 \cdot 3600 \text{ с} \approx 3,156 \cdot 10^7 \text{ с}$. Для оценки можно принять $T \approx 3,15 \cdot 10^7 \text{ с}$.

Найти:

Массу Солнца $M_С$.

Решение:

Будем считать, что Земля движется вокруг Солнца по круговой орбите. В этом случае движение Земли происходит под действием силы всемирного тяготения со стороны Солнца, которая сообщает Земле центростремительное ускорение.

Согласно второму закону Ньютона, сила, действующая на Землю, равна произведению массы Земли $m_З$ на ее центростремительное ускорение $a_ц$:

$F = m_З \cdot a_ц$

Силой, удерживающей Землю на орбите, является гравитационная сила:

$F_г = G \frac{M_С m_З}{R^2}$

Центростремительное ускорение тела, движущегося по окружности радиуса $\text{R}$ со скоростью $\text{v}$, равно:

$a_ц = \frac{v^2}{R}$

Приравниваем гравитационную силу и силу, вызывающую центростремительное движение:

$G \frac{M_С m_З}{R^2} = m_З \frac{v^2}{R}$

Масса Земли $m_З$ сокращается:

$G \frac{M_С}{R} = v^2$

Скорость движения Земли по орбите $\text{v}$ можно выразить через период обращения $\text{T}$ и радиус орбиты $\text{R}$. За время $\text{T}$ Земля проходит путь, равный длине окружности $2\pi R$:

$v = \frac{2\pi R}{T}$

Подставим выражение для скорости в предыдущую формулу:

$G \frac{M_С}{R} = \left(\frac{2\pi R}{T}\right)^2 = \frac{4\pi^2 R^2}{T^2}$

Выразим массу Солнца $M_С$:

$M_С = \frac{4\pi^2 R^3}{G T^2}$

Теперь подставим числовые значения в систему СИ и произведем вычисления, приняв $\pi \approx 3,14$:

$M_С = \frac{4 \cdot (3,14)^2 \cdot (1,5 \cdot 10^{11} \text{ м})^3}{6,67 \cdot 10^{-11} \frac{\text{Н} \cdot \text{м}^2}{\text{кг}^2} \cdot (3,15 \cdot 10^7 \text{ с})^2}$

$M_С = \frac{4 \cdot 9,86 \cdot 3,375 \cdot 10^{33}}{6,67 \cdot 10^{-11} \cdot 9,9225 \cdot 10^{14}} \text{ кг}$

$M_С \approx \frac{133,11 \cdot 10^{33}}{66,18 \cdot 10^3} \text{ кг} \approx \frac{1,33 \cdot 10^{35}}{6,62 \cdot 10^4} \text{ кг} \approx 2,01 \cdot 10^{30} \text{ кг}$

Округляя, получаем оценочное значение массы Солнца.

Ответ: Масса Солнца составляет примерно $2 \cdot 10^{30}$ кг.

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