Номер 3.6, 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 3.6, страница 18.

App\Models\Task {#1030 // resources/views/models/task/default.blade.php
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                            "field_translit" => "odinadcatyj"
                          ]
                          #original: array:6 [
                            "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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                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
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                          #hidden: []
                          #visible: []
                          #fillable: []
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                            0 => "*"
                          ]
                        }
                      ]
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                    }
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1207
                      #items: array:1 [
                        0 => App\Models\Term {#1208
                          #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" => 5158
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Илекса"
                            "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"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
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                          #relations: []
                          #touches: []
                          +timestamps: true
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                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1209
                      #items: array:3 [
                        0 => App\Models\Term {#1210
                          #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" => 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"
                            "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
                          ]
                          #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 {#1211
                          #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 {#1212
                          #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: []
                          #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 {#1213
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1214
                      #items: array:1 [
                        0 => App\Models\Term {#1215
                          #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" => 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"
                          ]
                          #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 {#1216
                      #items: array:1 [
                        0 => App\Models\Term {#1217
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "rossiya"
                          ]
                          #original: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "rossiya"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1218
                      #items: array:1 [
                        0 => App\Models\Term {#1219
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "moskva"
                          ]
                          #original: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "moskva"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
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                          #relations: []
                          #touches: []
                          +timestamps: true
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                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1220
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1221
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1222
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1223
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => "6"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1224
                      #items: array:1 [
                        0 => App\Models\Term {#1225
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 35
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "исправленное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "ispravlennoe"
                          ]
                          #original: array:6 [
                            "id" => 35
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "исправленное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "ispravlennoe"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1226
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => "мужчина в красном, летит на черном шаре"
                    "field_publication_year" => "2005"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1001"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_08/gelfgat-u/"
                    "field_isbn" => "978-5-89237-332-6"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_08/gelfgat-u/covers/cover1.webp?ts=1755898771"
                        "alt" => ""
                        "width" => "1813"
                        "height" => "2441"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1227
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1228
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1229
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/8-klass/fizika/ileksa-gelfgat-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1230
                      #items: array:1 [
                        0 => App\Models\Term {#1231
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "siniy"
                          ]
                          #original: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "siniy"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 379
                      "subject" => 556
                      "class_subject" => 492
                    ]
                  ]
                  #original: array:50 [
                    "id" => 5401
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_tree_default_status" => "tasks"
                    "field_pages_status" => null
                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1201}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1202}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1207}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1209}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1213}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1214}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1216}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1218}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1220}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1221}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1222}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1223}
                    "field_publication_number" => "6"
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1224}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1226}
                    "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 {#1227}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1228}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1229}
                    "field_url" => "/8-klass/fizika/ileksa-gelfgat-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1230}
                    "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
                    ]
                  ]
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                  #hidden: []
                  #visible: []
                  #fillable: []
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1232
              #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 {#1198}
            "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
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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 {#1234}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1232}
          ]
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          #dateFormat: null
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          #touches: []
          +timestamps: true
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          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Branch {#1233
          #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 {#1235
              #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 {#1236
              #items: array:1 [
                0 => App\Models\Book {#1199}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1237
              #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 {#1235}
            "field_page_start" => "5"
            "field_branch_display" => "0"
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            "field_branch_title_in_content" => "0"
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            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1236}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1237}
          ]
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          #attributeCastCache: []
          #dateFormat: null
          #appends: []
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          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1238
          #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 {#1239
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "18"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
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            "field_display_branch_page" => "1"
            "field_branch_title_in_content" => "0"
            "field_navigation_title" => null
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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 {#1240
              #items: array:1 [
                0 => App\Models\Book {#1199}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1317
              #items: array:1 [
                0 => App\Models\Branch {#1241
                  #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
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                    "field_branch_order" => null
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1243 …2}
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                    "field_description_bottom" => null
                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1242 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1277 …2}
                  ]
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                    "id" => 1287867
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                    "updated_at" => null
                    "field_display_title" => "Механика"
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                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1243 …2}
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                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1242 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1277 …2}
                  ]
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                    0 => "*"
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                }
              ]
              #escapeWhenCastingToString: false
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          #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 {#1239}
            "field_page_start" => "18"
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            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1240}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1317}
          ]
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            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1148
      #items: array:3 [
        0 => App\Models\Element {#1180
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
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          +exists: true
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          #attributes: array:7 [
            "id" => 1477780
            "created_at" => "2026-04-10 13:58:26"
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            "edition" => Illuminate\Database\Eloquent\Collection {#1172
              #items: array:1 [
                0 => App\Models\Edition {#1179
                  #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 {#1178 …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 {#1176 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1175 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1174 …2}
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                  ]
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                    "id" => 5410
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1178 …2}
                    "field_content_type" => "free"
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                    "field_process_formula" => "katex"
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                  ]
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                  #visible: []
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                    0 => "*"
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                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1288005"
              "type" => "task"
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            "text" => "<p><strong>3.6*.</strong> Известно, что при подъеме тела с поверхности Земли сила $\text{F}$ его притяжения к Земле уменьшается. А как изменяется эта сила при погружении тела в шахту, доходящую до центра Земли? Постройте график зависимости $F(r)$ для тела массой $\text{m}$, где $\text{r}$ — расстояние тела от центра Земли. Считайте Землю однородным шаром.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "6-1.jpg"
                "alt" => null
                "width" => "1428"
                "height" => 351
                "path" => "/media/fizika_08/gelfgat-u/0-03/6-1.webp?ts=1756049683"
              ]
            ]
          ]
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            "id" => 1477780
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1172}
            "task" => array:2 [
              "refs" => "1288005"
              "type" => "task"
            ]
            "text" => "<p><strong>3.6*.</strong> Известно, что при подъеме тела с поверхности Земли сила $\text{F}$ его притяжения к Земле уменьшается. А как изменяется эта сила при погружении тела в шахту, доходящую до центра Земли? Постройте график зависимости $F(r)$ для тела массой $\text{m}$, где $\text{r}$ — расстояние тела от центра Земли. Считайте Землю однородным шаром.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "6-1.jpg"
                "alt" => null
                "width" => "1428"
                "height" => 351
                "path" => "/media/fizika_08/gelfgat-u/0-03/6-1.webp?ts=1756049683"
              ]
            ]
          ]
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            0 => "*"
          ]
        }
        1 => App\Models\Element {#1173
          #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" => 1478145
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1164
              #items: array:1 [
                0 => App\Models\Edition {#1171
                  #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 {#1170 …2}
                    "field_content_type" => "free"
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                    "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 {#1167 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1168 …2}
                    "field_process_formula" => ""
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1166 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
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                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1170 …2}
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                  ]
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                  #visible: []
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                    0 => "*"
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              ]
              #escapeWhenCastingToString: false
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            "task" => array:2 [
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            "img" => array:2 [
              0 => array:5 [
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                "width" => "1442"
                "height" => 844
                "path" => "/media/fizika_08/gelfgat-u/1-03/6-1.webp?ts=1756049746"
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              1 => array:5 [
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                "height" => 565
                "path" => "/media/fizika_08/gelfgat-u/1-03/6-2.webp?ts=1756049746"
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            "id" => 1478145
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1164}
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              ]
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              ]
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          ]
          #changes: []
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                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение 2"
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            "text" => "<p><strong>Решение</strong></p><p>Для решения задачи рассмотрим два случая: когда тело находится внутри Земли (в шахте) и когда оно находится на её поверхности или выше. Пусть $\text{m}$ — масса тела, $\text{M}$ — масса Земли, $\text{R}$ — радиус Земли, $\text{r}$ — расстояние от тела до центра Земли, $\text{G}$ — гравитационная постоянная, а $\rho$ — средняя плотность Земли, которая по условию постоянна.</p><p><strong>Случай 1: Тело находится внутри Земли ($0 \leq r \leq R$)</strong></p><p>Согласно теореме Гаусса для гравитации (или следствию из неё, известному как теорема о сферической оболочке), сила притяжения, действующая на тело внутри сферически-симметричного объекта, создается только той массой, которая находится внутри сферы с радиусом $\text{r}$. Внешний сферический слой не оказывает на тело гравитационного воздействия.</p><p>Массу Земли $\text{M}$ можно выразить через её плотность $\rho$ и объём $V = \frac{4}{3}\pi R^3$ как $M = \rho V = \rho \frac{4}{3}\pi R^3$. Отсюда плотность Земли: $\rho = \frac{M}{\frac{4}{3}\pi R^3}$.</p><p>Масса $M'$ части Земли, находящейся внутри сферы радиусом $\text{r}$, равна $M' = \rho \cdot V' = \rho \cdot \frac{4}{3}\pi r^3$. Подставив выражение для плотности $\rho$, получим: $M' = \frac{M}{\frac{4}{3}\pi R^3} \cdot \frac{4}{3}\pi r^3 = M \frac{r^3}{R^3}$.</p><p>Теперь по закону всемирного тяготения найдём силу $\text{F}$, действующую на тело массой $\text{m}$ со стороны массы $M'$: $F(r) = G \frac{M'm}{r^2} = G \frac{(M \frac{r^3}{R^3}) m}{r^2} = G \frac{Mm}{R^3} r$.</p><p>Из этой формулы видно, что внутри Земли сила притяжения $\text{F}$ прямо пропорциональна расстоянию $\text{r}$ до её центра. При $r=0$ (в центре Земли) сила притяжения равна нулю.</p><p><strong>Случай 2: Тело находится на поверхности или вне Земли ($r \geq R$)</strong></p><p>В этом случае Земля притягивает тело так, как будто вся её масса $\text{M}$ сосредоточена в центре. Сила притяжения описывается стандартной формулой закона всемирного тяготения: $F(r) = G \frac{Mm}{r^2}$.</p><p>Эта формула показывает, что вне Земли сила притяжения уменьшается обратно пропорционально квадрату расстояния от её центра. На поверхности Земли, при $r=R$, сила максимальна и равна $F_{max} = G \frac{Mm}{R^2}$.</p><p><strong>Вывод и построение графика</strong></p><p>При погружении тела в шахту от поверхности к центру Земли сила притяжения будет уменьшаться линейно, от максимального значения $F_{max}$ на поверхности до нуля в центре.</p><p>График зависимости $F(r)$ будет состоять из двух участков. Первый участок, при $0 \leq r \leq R$, представляет собой прямую линию, выходящую из начала координат и идущую до точки с координатами $(R, G\frac{Mm}{R^2})$. Это соответствует функции $F(r) = (G\frac{Mm}{R^3}) \cdot r$. Второй участок, при $r \geq R$, представляет собой кривую, убывающую по закону обратных квадратов, согласно функции $F(r) = G\frac{Mm}{r^2}$. Графически это выглядит как линейный рост силы от центра до поверхности Земли, а затем спад по закону обратных квадратов при удалении от неё.</p><p><strong>Ответ:</strong> При погружении тела в шахту от поверхности к центру Земли сила его притяжения к Земле уменьшается прямо пропорционально расстоянию до центра, становясь равной нулю в центре Земли. График зависимости силы притяжения $\text{F}$ от расстояния $\text{r}$ до центра Земли представляет собой прямую линию, идущую из начала координат до точки, соответствующей поверхности Земли (где сила максимальна), после чего график переходит в кривую, убывающую обратно пропорционально квадрату расстояния.</p>"
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          #original: array:6 [
            "id" => 1737698
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1156}
            "task" => array:2 [
              "refs" => "1288005"
              "type" => "task"
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            "text" => "<p><strong>Решение</strong></p><p>Для решения задачи рассмотрим два случая: когда тело находится внутри Земли (в шахте) и когда оно находится на её поверхности или выше. Пусть $\text{m}$ — масса тела, $\text{M}$ — масса Земли, $\text{R}$ — радиус Земли, $\text{r}$ — расстояние от тела до центра Земли, $\text{G}$ — гравитационная постоянная, а $\rho$ — средняя плотность Земли, которая по условию постоянна.</p><p><strong>Случай 1: Тело находится внутри Земли ($0 \leq r \leq R$)</strong></p><p>Согласно теореме Гаусса для гравитации (или следствию из неё, известному как теорема о сферической оболочке), сила притяжения, действующая на тело внутри сферически-симметричного объекта, создается только той массой, которая находится внутри сферы с радиусом $\text{r}$. Внешний сферический слой не оказывает на тело гравитационного воздействия.</p><p>Массу Земли $\text{M}$ можно выразить через её плотность $\rho$ и объём $V = \frac{4}{3}\pi R^3$ как $M = \rho V = \rho \frac{4}{3}\pi R^3$. Отсюда плотность Земли: $\rho = \frac{M}{\frac{4}{3}\pi R^3}$.</p><p>Масса $M'$ части Земли, находящейся внутри сферы радиусом $\text{r}$, равна $M' = \rho \cdot V' = \rho \cdot \frac{4}{3}\pi r^3$. Подставив выражение для плотности $\rho$, получим: $M' = \frac{M}{\frac{4}{3}\pi R^3} \cdot \frac{4}{3}\pi r^3 = M \frac{r^3}{R^3}$.</p><p>Теперь по закону всемирного тяготения найдём силу $\text{F}$, действующую на тело массой $\text{m}$ со стороны массы $M'$: $F(r) = G \frac{M'm}{r^2} = G \frac{(M \frac{r^3}{R^3}) m}{r^2} = G \frac{Mm}{R^3} r$.</p><p>Из этой формулы видно, что внутри Земли сила притяжения $\text{F}$ прямо пропорциональна расстоянию $\text{r}$ до её центра. При $r=0$ (в центре Земли) сила притяжения равна нулю.</p><p><strong>Случай 2: Тело находится на поверхности или вне Земли ($r \geq R$)</strong></p><p>В этом случае Земля притягивает тело так, как будто вся её масса $\text{M}$ сосредоточена в центре. Сила притяжения описывается стандартной формулой закона всемирного тяготения: $F(r) = G \frac{Mm}{r^2}$.</p><p>Эта формула показывает, что вне Земли сила притяжения уменьшается обратно пропорционально квадрату расстояния от её центра. На поверхности Земли, при $r=R$, сила максимальна и равна $F_{max} = G \frac{Mm}{R^2}$.</p><p><strong>Вывод и построение графика</strong></p><p>При погружении тела в шахту от поверхности к центру Земли сила притяжения будет уменьшаться линейно, от максимального значения $F_{max}$ на поверхности до нуля в центре.</p><p>График зависимости $F(r)$ будет состоять из двух участков. Первый участок, при $0 \leq r \leq R$, представляет собой прямую линию, выходящую из начала координат и идущую до точки с координатами $(R, G\frac{Mm}{R^2})$. Это соответствует функции $F(r) = (G\frac{Mm}{R^3}) \cdot r$. Второй участок, при $r \geq R$, представляет собой кривую, убывающую по закону обратных квадратов, согласно функции $F(r) = G\frac{Mm}{r^2}$. Графически это выглядит как линейный рост силы от центра до поверхности Земли, а затем спад по закону обратных квадратов при удалении от неё.</p><p><strong>Ответ:</strong> При погружении тела в шахту от поверхности к центру Земли сила его притяжения к Земле уменьшается прямо пропорционально расстоянию до центра, становясь равной нулю в центре Земли. График зависимости силы притяжения $\text{F}$ от расстояния $\text{r}$ до центра Земли представляет собой прямую линию, идущую из начала координат до точки, соответствующей поверхности Земли (где сила максимальна), после чего график переходит в кривую, убывающую обратно пропорционально квадрату расстояния.</p>"
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№3.6 (с. 18)
Условие. №3.6 (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 3.6, Условие

3.6*. Известно, что при подъеме тела с поверхности Земли сила $\text{F}$ его притяжения к Земле уменьшается. А как изменяется эта сила при погружении тела в шахту, доходящую до центра Земли? Постройте график зависимости $F(r)$ для тела массой $\text{m}$, где $\text{r}$ — расстояние тела от центра Земли. Считайте Землю однородным шаром.

Решение. №3.6 (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 3.6, Решение
Физика, 8-11 класс Учебник, задачник, авторы: Гельфгат Илья Маркович, Генденштейн Лев Элевич, Кирик Леонид Анатольевич, издательство Илекса, Москва, 2005, страница 18, номер 3.6, Решение (продолжение 2)
Решение 2. №3.6 (с. 18)

Решение

Для решения задачи рассмотрим два случая: когда тело находится внутри Земли (в шахте) и когда оно находится на её поверхности или выше. Пусть $\text{m}$ — масса тела, $\text{M}$ — масса Земли, $\text{R}$ — радиус Земли, $\text{r}$ — расстояние от тела до центра Земли, $\text{G}$ — гравитационная постоянная, а $\rho$ — средняя плотность Земли, которая по условию постоянна.

Случай 1: Тело находится внутри Земли ($0 \leq r \leq R$)

Согласно теореме Гаусса для гравитации (или следствию из неё, известному как теорема о сферической оболочке), сила притяжения, действующая на тело внутри сферически-симметричного объекта, создается только той массой, которая находится внутри сферы с радиусом $\text{r}$. Внешний сферический слой не оказывает на тело гравитационного воздействия.

Массу Земли $\text{M}$ можно выразить через её плотность $\rho$ и объём $V = \frac{4}{3}\pi R^3$ как $M = \rho V = \rho \frac{4}{3}\pi R^3$. Отсюда плотность Земли: $\rho = \frac{M}{\frac{4}{3}\pi R^3}$.

Масса $M'$ части Земли, находящейся внутри сферы радиусом $\text{r}$, равна $M' = \rho \cdot V' = \rho \cdot \frac{4}{3}\pi r^3$. Подставив выражение для плотности $\rho$, получим: $M' = \frac{M}{\frac{4}{3}\pi R^3} \cdot \frac{4}{3}\pi r^3 = M \frac{r^3}{R^3}$.

Теперь по закону всемирного тяготения найдём силу $\text{F}$, действующую на тело массой $\text{m}$ со стороны массы $M'$: $F(r) = G \frac{M'm}{r^2} = G \frac{(M \frac{r^3}{R^3}) m}{r^2} = G \frac{Mm}{R^3} r$.

Из этой формулы видно, что внутри Земли сила притяжения $\text{F}$ прямо пропорциональна расстоянию $\text{r}$ до её центра. При $r=0$ (в центре Земли) сила притяжения равна нулю.

Случай 2: Тело находится на поверхности или вне Земли ($r \geq R$)

В этом случае Земля притягивает тело так, как будто вся её масса $\text{M}$ сосредоточена в центре. Сила притяжения описывается стандартной формулой закона всемирного тяготения: $F(r) = G \frac{Mm}{r^2}$.

Эта формула показывает, что вне Земли сила притяжения уменьшается обратно пропорционально квадрату расстояния от её центра. На поверхности Земли, при $r=R$, сила максимальна и равна $F_{max} = G \frac{Mm}{R^2}$.

Вывод и построение графика

При погружении тела в шахту от поверхности к центру Земли сила притяжения будет уменьшаться линейно, от максимального значения $F_{max}$ на поверхности до нуля в центре.

График зависимости $F(r)$ будет состоять из двух участков. Первый участок, при $0 \leq r \leq R$, представляет собой прямую линию, выходящую из начала координат и идущую до точки с координатами $(R, G\frac{Mm}{R^2})$. Это соответствует функции $F(r) = (G\frac{Mm}{R^3}) \cdot r$. Второй участок, при $r \geq R$, представляет собой кривую, убывающую по закону обратных квадратов, согласно функции $F(r) = G\frac{Mm}{r^2}$. Графически это выглядит как линейный рост силы от центра до поверхности Земли, а затем спад по закону обратных квадратов при удалении от неё.

Ответ: При погружении тела в шахту от поверхности к центру Земли сила его притяжения к Земле уменьшается прямо пропорционально расстоянию до центра, становясь равной нулю в центре Земли. График зависимости силы притяжения $\text{F}$ от расстояния $\text{r}$ до центра Земли представляет собой прямую линию, идущую из начала координат до точки, соответствующей поверхности Земли (где сила максимальна), после чего график переходит в кривую, убывающую обратно пропорционально квадрату расстояния.

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