Номер 9, страница 89, часть 1 - гдз по физике 9 класс рабочая тетрадь Грачев, Погожев

Авторы: Грачев А. В., Погожев В. А., Боков П. Ю., Вишнякова Е. А.

Тип: рабочая тетрадь

Издательство: Просвещение

Год издания: 2021 - 2026

Часть: 1

Цвет обложки: синий

ISBN: 978-5-09-098826-1 (ч.1) 978-5-09-098880-3 (ч.2) 978-5-09-098881-0 (ч.3)

Часть 1. Глава 2. Динамика. Параграф 18. Силы всемирного тяготения. Закон всемирного тяготения - номер 9, страница 89.

App\Models\Task {#1030 // resources/views/models/task/default.blade.php
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Просвещение"
                            "field_cases" => null
                            "field_translit" => "prosveschenie"
                          ]
                          #original: array:6 [
                            "id" => 5153
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Просвещение"
                            "field_cases" => null
                            "field_translit" => "prosveschenie"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1207
                      #items: array:4 [
                        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:12 [
                            "id" => 4180
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Грачев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Александр"
                            "field_patronymic" => "Васильевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4180
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Грачев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Александр"
                            "field_patronymic" => "Васильевич"
                            "field_surname_rp" => null
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                        1 => App\Models\Term {#1209
                          #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" => 5484
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Погожев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Владимир"
                            "field_patronymic" => "Александрович"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 5484
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Погожев"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Владимир"
                            "field_patronymic" => "Александрович"
                            "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 => "*"
                          ]
                        }
                        2 => 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" => 3888
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Боков"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Павел"
                            "field_patronymic" => "Юрьевич"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 3888
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Боков"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Павел"
                            "field_patronymic" => "Юрьевич"
                            "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 => "*"
                          ]
                        }
                        3 => 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" => 4007
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Вишнякова"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Екатерина"
                            "field_patronymic" => "Анатольевна"
                            "field_surname_rp" => null
                          ]
                          #original: array:12 [
                            "id" => 4007
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Вишнякова"
                            "field_bio" => null
                            "field_degree_rp" => null
                            "field_foreign_lang_name" => null
                            "field_foreign_lang_patronymic" => null
                            "field_foreign_lang_surname" => null
                            "field_name" => "Екатерина"
                            "field_patronymic" => "Анатольевна"
                            "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 {#1212
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1213
                      #items: array:1 [
                        0 => App\Models\Term {#1214
                          #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" => 6736
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "рабочая тетрадь"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => "рабочие тетради"
                            "field_short_name" => "рт"
                            "field_short_name_foreign" => null
                            "field_translit" => "rabochaya tetrad"
                          ]
                          #original: array:10 [
                            "id" => 6736
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "рабочая тетрадь"
                            "field_book_type_foreign" => null
                            "field_cases" => array:6 [ …6]
                            "field_plural_form" => "рабочие тетради"
                            "field_short_name" => "рт"
                            "field_short_name_foreign" => null
                            "field_translit" => "rabochaya tetrad"
                          ]
                          #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 {#1215
                      #items: array:1 [
                        0 => App\Models\Term {#1216
                          #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 {#1217
                      #items: array:1 [
                        0 => App\Models\Term {#1218
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "moskva"
                          ]
                          #original: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "moskva"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1219
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1220
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1221
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1222
                      #items: array:1 [
                        0 => App\Models\Term {#1223
                          #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" => 6706
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "ФГОС (старый)"
                            "field_cases" => array:6 [ …6]
                            "field_color" => null
                            "field_end_year" => "2022"
                            "field_start_year" => "2019"
                            "field_translit" => "fgos-old"
                            "field_type" => null
                          ]
                          #original: array:10 [
                            "id" => 6706
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "ФГОС (старый)"
                            "field_cases" => array:6 [ …6]
                            "field_color" => null
                            "field_end_year" => "2022"
                            "field_start_year" => "2019"
                            "field_translit" => "fgos-old"
                            "field_type" => 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_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" => 33
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "stereotipnoe"
                          ]
                          #original: array:6 [
                            "id" => 33
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "стереотипное"
                            "field_cases" => array:6 [ …6]
                            "field_translit" => "stereotipnoe"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1226
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2021"
                    "field_publication_year_until" => null
                    "field_part" => "1, 2, 3"
                    "field_part_writing" => "Часть"
                    "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" => "594"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/grachev-rt/"
                    "field_isbn" => "978-5-09-098826-1 (ч.1) 978-5-09-098880-3 (ч.2) 978-5-09-098881-0 (ч.3)"
                    "field_cover" => array:3 [
                      0 => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
                      1 => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
                      2 => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                    ]
                    "field_cover_alts" => array:3 [
                      0 => ""
                      1 => ""
                      2 => ""
                    ]
                    "field_covers" => array:3 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2293"
                        "height" => "2989"
                      ]
                      1 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2265"
                        "height" => "3003"
                      ]
                      2 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2241"
                        "height" => "2999"
                      ]
                    ]
                    "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" => "/9-klass/fizika/grachev-rabochaya-tetrad"
                    "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" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
                  #original: array:50 [
                    "id" => 1203
                    "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 {#1202}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1203}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1205}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1207}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1212}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1213}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1215}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1217}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1219}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1220}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1221}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1222}
                    "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" => null
                    "field_publication_year" => "2021"
                    "field_publication_year_until" => null
                    "field_part" => "1, 2, 3"
                    "field_part_writing" => "Часть"
                    "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" => "594"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_09/grachev-rt/"
                    "field_isbn" => "978-5-09-098826-1 (ч.1) 978-5-09-098880-3 (ч.2) 978-5-09-098881-0 (ч.3)"
                    "field_cover" => array:3 [
                      0 => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
                      1 => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
                      2 => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                    ]
                    "field_cover_alts" => array:3 [
                      0 => ""
                      1 => ""
                      2 => ""
                    ]
                    "field_covers" => array:3 [
                      0 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2293"
                        "height" => "2989"
                      ]
                      1 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2265"
                        "height" => "3003"
                      ]
                      2 => array:4 [
                        "path" => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                        "alt" => ""
                        "width" => "2241"
                        "height" => "2999"
                      ]
                    ]
                    "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" => "/9-klass/fizika/grachev-rabochaya-tetrad"
                    "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" => 380
                      "subject" => 556
                      "class_subject" => 493
                    ]
                  ]
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                  #attributeCastCache: []
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1232
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1434806
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => null
            "field_branch_order" => "1"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1201}
            "field_page_start" => "4"
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            "field_branch_covers" => []
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            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1232}
          ]
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          #dateFormat: null
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          #hidden: []
          #visible: []
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            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
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          #attributes: array:24 [
            "id" => 1434820
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Динамика"
            "field_branch_order" => "2"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1238
              #items: array:1 [
                0 => App\Models\Term {#1235
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
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                  +exists: true
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                  #escapeWhenCastingToString: false
                  #attributes: array:7 [
                    "id" => 29
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Глава"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
                    "field_short_name" => null
                  ]
                  #original: array:7 [
                    "id" => 29
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Глава"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
                    "field_short_name" => null
                  ]
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                  #attributeCastCache: []
                  #dateFormat: null
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                  #touches: []
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                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "53"
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            "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 {#1237
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                0 => App\Models\Book {#1200}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1236
              #items: array:1 [
                0 => App\Models\Branch {#1034}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1434820
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Динамика"
            "field_branch_order" => "2"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1238}
            "field_page_start" => "53"
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            "field_branch_covers" => []
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          #dateFormat: null
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          #hidden: []
          #visible: []
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          #guarded: array:1 [
            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1239
          #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" => 1434827
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Силы всемирного тяготения. Закон всемирного тяготения"
            "field_branch_order" => "18"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1243
              #items: array:1 [
                0 => App\Models\Term {#1240
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #original: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #changes: []
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                  #attributeCastCache: []
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
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            "field_page_start" => "87"
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                0 => App\Models\Book {#1200}
              ]
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            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1319
              #items: array:1 [
                0 => App\Models\Branch {#1241
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
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                    "book" => Illuminate\Database\Eloquent\Collection {#1246 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1279 …2}
                  ]
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                    "updated_at" => null
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            "id" => 1434827
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
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      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1112
      #items: array:2 [
        0 => App\Models\Element {#1181
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
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          #escapeWhenCastingToString: false
          #attributes: array:7 [
            "id" => 1698405
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1172
              #items: array:1 [
                0 => App\Models\Edition {#1180
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
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                  #perPage: 15
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                  #attributes: array:21 [
                    "id" => 6173
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1177 …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 {#1178 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1175 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1176 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6173
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1177 …2}
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                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1178 …2}
                    "field_comment" => null
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                  ]
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                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1435017"
              "type" => "task"
            ]
            "text" => "<p><strong>9*.</strong> На экваторе некоторой планеты, лишённой атмосферы, вес тела в 2 раза меньше, чем на полюсе. Считая планету однородным шаром с плотностью вещества $\rho = 3 \text{ т/м}^3$, оцените длительность суток на этой планете. (Объём шара вычисляют по формуле $V = \frac{4\pi R^3}{3}$.)</p><p><em>Решение.</em></p><p><em>Ответ:</em> ___________.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "9-1.jpg"
                "alt" => null
                "width" => "1939"
                "height" => 868
                "path" => "/media/fizika_09/grachev-rt/0-18/9-1.webp?ts=1759402700"
              ]
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            "text" => "<p><strong>Дано:</strong></p><p>Вес тела на экваторе в 2 раза меньше, чем на полюсе: $P_{пол} = 2 P_{экв}$.<br>Плотность планеты: $\rho = 3$ т/м$^3$.</p><p>Перевод в систему СИ:<br>$\rho = 3 \text{ т/м}^3 = 3 \cdot 1000 \text{ кг/м}^3 = 3000 \text{ кг/м}^3$.</p><p><strong>Найти:</strong></p><p>Длительность суток на планете $T$.</p><p><strong>Решение:</strong></p><p>Вес тела на полюсе $P_{пол}$ определяется только силой гравитационного притяжения, так как на полюсе тело не испытывает действия центробежной силы из-за вращения планеты.</p><p>$P_{пол} = F_g = mg$</p><p>где $m$ — масса тела, $g$ — ускорение свободного падения на поверхности планеты.</p><p>На экваторе вес тела $P_{экв}$ уменьшается за счет центробежной силы инерции, направленной против силы тяжести. Согласно второму закону Ньютона, сила тяжести сообщает телу центростремительное ускорение $a_ц$:</p><p>$F_g - P_{экв} = m a_ц$</p><p>Отсюда вес на экваторе:</p><p>$P_{экв} = F_g - m a_ц = mg - m\omega^2 R$</p><p>где $\omega$ — угловая скорость вращения планеты, а $R$ — её радиус.</p><p>По условию задачи $P_{пол} = 2 P_{экв}$. Подставим выражения для веса:</p><p>$mg = 2(mg - m\omega^2 R)$</p><p>Сократив на массу тела $m$, получим:</p><p>$g = 2(g - \omega^2 R)$<br>$g = 2g - 2\omega^2 R$<br>$g = 2\omega^2 R$</p><p>Ускорение свободного падения $g$ на поверхности шарообразной планеты можно выразить через её массу $M$ и радиус $R$:</p><p>$g = \frac{GM}{R^2}$</p><p>где $G$ — гравитационная постоянная. Массу планеты $M$ выразим через её плотность $\rho$ и объём $V = \frac{4}{3}\pi R^3$:</p><p>$M = \rho V = \rho \frac{4}{3}\pi R^3$</p><p>Тогда ускорение свободного падения:</p><p>$g = \frac{G \cdot \rho \frac{4}{3}\pi R^3}{R^2} = \frac{4}{3}\pi G \rho R$</p><p>Подставим это выражение для $g$ в соотношение $g = 2\omega^2 R$:</p><p>$\frac{4}{3}\pi G \rho R = 2\omega^2 R$</p><p>Сократим на $2R$ (считая $R \ne 0$):</p><p>$\frac{2}{3}\pi G \rho = \omega^2$</p><p>Длительность суток $T$ (период вращения) связана с угловой скоростью $\omega$ формулой $T = \frac{2\pi}{\omega}$. Выразим $T$:</p><p>$T = \frac{2\pi}{\omega} = \frac{2\pi}{\sqrt{\frac{2}{3}\pi G \rho}} = 2\pi\sqrt{\frac{3}{2\pi G \rho}} = \sqrt{\frac{4\pi^2 \cdot 3}{2\pi G \rho}} = \sqrt{\frac{6\pi}{G \rho}}$</p><p>Теперь подставим числовые значения. Гравитационная постоянная $G \approx 6.67 \times 10^{-11}$ Н·м$^2$/кг$^2$.</p><p>$T = \sqrt{\frac{6 \cdot 3.14}{6.67 \times 10^{-11} \mathrm{Н \cdot м}^2/\text{кг}^2 \cdot 3000 \text{ кг/м}^3}} \approx \sqrt{\frac{18.84}{2.001 \times 10^{-7} \text{ с}^{-2}}} \approx \sqrt{9.415 \times 10^7 \text{ с}^2} \approx 9703 \text{ с}$</p><p>Переведем полученное значение в часы и минуты:</p><p>$9703 \text{ с} = \frac{9703}{3600} \text{ ч} \approx 2.695 \text{ ч} \approx 2 \text{ часа } + 0.695 \cdot 60 \text{ мин} \approx 2 \text{ часа } 42 \text{ минуты}$</p><p><strong>Ответ:</strong> длительность суток на этой планете составляет примерно 2 часа 42 минуты.</p>"
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            "text" => "<p><strong>Дано:</strong></p><p>Вес тела на экваторе в 2 раза меньше, чем на полюсе: $P_{пол} = 2 P_{экв}$.<br>Плотность планеты: $\rho = 3$ т/м$^3$.</p><p>Перевод в систему СИ:<br>$\rho = 3 \text{ т/м}^3 = 3 \cdot 1000 \text{ кг/м}^3 = 3000 \text{ кг/м}^3$.</p><p><strong>Найти:</strong></p><p>Длительность суток на планете $T$.</p><p><strong>Решение:</strong></p><p>Вес тела на полюсе $P_{пол}$ определяется только силой гравитационного притяжения, так как на полюсе тело не испытывает действия центробежной силы из-за вращения планеты.</p><p>$P_{пол} = F_g = mg$</p><p>где $m$ — масса тела, $g$ — ускорение свободного падения на поверхности планеты.</p><p>На экваторе вес тела $P_{экв}$ уменьшается за счет центробежной силы инерции, направленной против силы тяжести. Согласно второму закону Ньютона, сила тяжести сообщает телу центростремительное ускорение $a_ц$:</p><p>$F_g - P_{экв} = m a_ц$</p><p>Отсюда вес на экваторе:</p><p>$P_{экв} = F_g - m a_ц = mg - m\omega^2 R$</p><p>где $\omega$ — угловая скорость вращения планеты, а $R$ — её радиус.</p><p>По условию задачи $P_{пол} = 2 P_{экв}$. Подставим выражения для веса:</p><p>$mg = 2(mg - m\omega^2 R)$</p><p>Сократив на массу тела $m$, получим:</p><p>$g = 2(g - \omega^2 R)$<br>$g = 2g - 2\omega^2 R$<br>$g = 2\omega^2 R$</p><p>Ускорение свободного падения $g$ на поверхности шарообразной планеты можно выразить через её массу $M$ и радиус $R$:</p><p>$g = \frac{GM}{R^2}$</p><p>где $G$ — гравитационная постоянная. Массу планеты $M$ выразим через её плотность $\rho$ и объём $V = \frac{4}{3}\pi R^3$:</p><p>$M = \rho V = \rho \frac{4}{3}\pi R^3$</p><p>Тогда ускорение свободного падения:</p><p>$g = \frac{G \cdot \rho \frac{4}{3}\pi R^3}{R^2} = \frac{4}{3}\pi G \rho R$</p><p>Подставим это выражение для $g$ в соотношение $g = 2\omega^2 R$:</p><p>$\frac{4}{3}\pi G \rho R = 2\omega^2 R$</p><p>Сократим на $2R$ (считая $R \ne 0$):</p><p>$\frac{2}{3}\pi G \rho = \omega^2$</p><p>Длительность суток $T$ (период вращения) связана с угловой скоростью $\omega$ формулой $T = \frac{2\pi}{\omega}$. Выразим $T$:</p><p>$T = \frac{2\pi}{\omega} = \frac{2\pi}{\sqrt{\frac{2}{3}\pi G \rho}} = 2\pi\sqrt{\frac{3}{2\pi G \rho}} = \sqrt{\frac{4\pi^2 \cdot 3}{2\pi G \rho}} = \sqrt{\frac{6\pi}{G \rho}}$</p><p>Теперь подставим числовые значения. Гравитационная постоянная $G \approx 6.67 \times 10^{-11}$ Н·м$^2$/кг$^2$.</p><p>$T = \sqrt{\frac{6 \cdot 3.14}{6.67 \times 10^{-11} \mathrm{Н \cdot м}^2/\text{кг}^2 \cdot 3000 \text{ кг/м}^3}} \approx \sqrt{\frac{18.84}{2.001 \times 10^{-7} \text{ с}^{-2}}} \approx \sqrt{9.415 \times 10^7 \text{ с}^2} \approx 9703 \text{ с}$</p><p>Переведем полученное значение в часы и минуты:</p><p>$9703 \text{ с} = \frac{9703}{3600} \text{ ч} \approx 2.695 \text{ ч} \approx 2 \text{ часа } + 0.695 \cdot 60 \text{ мин} \approx 2 \text{ часа } 42 \text{ минуты}$</p><p><strong>Ответ:</strong> длительность суток на этой планете составляет примерно 2 часа 42 минуты.</p>"
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№9 (с. 89)
Условие. №9 (с. 89)
скриншот условия
Физика, 9 класс рабочая тетрадь, авторы: Грачев Александр Васильевич, Погожев Владимир Александрович, Боков Павел Юрьевич, Вишнякова Екатерина Анатольевна, издательство Просвещение, Москва, 2021, Часть 1, страница 89, номер 9, Условие

9*. На экваторе некоторой планеты, лишённой атмосферы, вес тела в 2 раза меньше, чем на полюсе. Считая планету однородным шаром с плотностью вещества $\rho = 3 \text{ т/м}^3$, оцените длительность суток на этой планете. (Объём шара вычисляют по формуле $V = \frac{4\pi R^3}{3}$.)

Решение.

Ответ: ___________.

Решение. №9 (с. 89)

Дано:

Вес тела на экваторе в 2 раза меньше, чем на полюсе: $P_{пол} = 2 P_{экв}$.
Плотность планеты: $\rho = 3$ т/м$^3$.

Перевод в систему СИ:
$\rho = 3 \text{ т/м}^3 = 3 \cdot 1000 \text{ кг/м}^3 = 3000 \text{ кг/м}^3$.

Найти:

Длительность суток на планете $T$.

Решение:

Вес тела на полюсе $P_{пол}$ определяется только силой гравитационного притяжения, так как на полюсе тело не испытывает действия центробежной силы из-за вращения планеты.

$P_{пол} = F_g = mg$

где $m$ — масса тела, $g$ — ускорение свободного падения на поверхности планеты.

На экваторе вес тела $P_{экв}$ уменьшается за счет центробежной силы инерции, направленной против силы тяжести. Согласно второму закону Ньютона, сила тяжести сообщает телу центростремительное ускорение $a_ц$:

$F_g - P_{экв} = m a_ц$

Отсюда вес на экваторе:

$P_{экв} = F_g - m a_ц = mg - m\omega^2 R$

где $\omega$ — угловая скорость вращения планеты, а $R$ — её радиус.

По условию задачи $P_{пол} = 2 P_{экв}$. Подставим выражения для веса:

$mg = 2(mg - m\omega^2 R)$

Сократив на массу тела $m$, получим:

$g = 2(g - \omega^2 R)$
$g = 2g - 2\omega^2 R$
$g = 2\omega^2 R$

Ускорение свободного падения $g$ на поверхности шарообразной планеты можно выразить через её массу $M$ и радиус $R$:

$g = \frac{GM}{R^2}$

где $G$ — гравитационная постоянная. Массу планеты $M$ выразим через её плотность $\rho$ и объём $V = \frac{4}{3}\pi R^3$:

$M = \rho V = \rho \frac{4}{3}\pi R^3$

Тогда ускорение свободного падения:

$g = \frac{G \cdot \rho \frac{4}{3}\pi R^3}{R^2} = \frac{4}{3}\pi G \rho R$

Подставим это выражение для $g$ в соотношение $g = 2\omega^2 R$:

$\frac{4}{3}\pi G \rho R = 2\omega^2 R$

Сократим на $2R$ (считая $R \ne 0$):

$\frac{2}{3}\pi G \rho = \omega^2$

Длительность суток $T$ (период вращения) связана с угловой скоростью $\omega$ формулой $T = \frac{2\pi}{\omega}$. Выразим $T$:

$T = \frac{2\pi}{\omega} = \frac{2\pi}{\sqrt{\frac{2}{3}\pi G \rho}} = 2\pi\sqrt{\frac{3}{2\pi G \rho}} = \sqrt{\frac{4\pi^2 \cdot 3}{2\pi G \rho}} = \sqrt{\frac{6\pi}{G \rho}}$

Теперь подставим числовые значения. Гравитационная постоянная $G \approx 6.67 \times 10^{-11}$ Н·м$^2$/кг$^2$.

$T = \sqrt{\frac{6 \cdot 3.14}{6.67 \times 10^{-11} \mathrm{Н \cdot м}^2/\text{кг}^2 \cdot 3000 \text{ кг/м}^3}} \approx \sqrt{\frac{18.84}{2.001 \times 10^{-7} \text{ с}^{-2}}} \approx \sqrt{9.415 \times 10^7 \text{ с}^2} \approx 9703 \text{ с}$

Переведем полученное значение в часы и минуты:

$9703 \text{ с} = \frac{9703}{3600} \text{ ч} \approx 2.695 \text{ ч} \approx 2 \text{ часа } + 0.695 \cdot 60 \text{ мин} \approx 2 \text{ часа } 42 \text{ минуты}$

Ответ: длительность суток на этой планете составляет примерно 2 часа 42 минуты.

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