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Номер 28, страница 105, часть 1 - гдз по физике 9 класс учебник Генденштейн, Булатова
Авторы: Генденштейн Л. Э., Булатова А. А., Корнильев И. Н., Кошкина А. В.
Тип: Учебник
Издательство: Бином
Год издания: 2016 - 2026
Часть: 1
Цвет обложки: бирюзовый
ISBN: 978-5-9963-3062-1
Популярные ГДЗ в 9 классе
Часть 1. Механические явления. Глава II. Динамика. Параграф 11. Силы трения - номер 28, страница 105.
App\Models\Task {#1024 // resources/views/models/task/default.blade.php #connection: "mysql" #table: "tasks" #primaryKey: "id" #keyType: "int" +incrementing: true #with: [] #withCount: [] +preventsLazyLoading: false #perPage: 15 +exists: true +wasRecentlyCreated: false #escapeWhenCastingToString: false #attributes: array:24 [ "id" => 1433643 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "105" "field_page_end" => null "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik/11-28" "field_display_title" => "28" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#331 #items: array:1 [ 0 => App\Models\Term {#1029 #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" => 26 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "name" => "номер" "field_cases" => array:6 [ "field_accusative_case" => "номер" "field_creative_case" => "номером" "field_dative_case" => "номеру" "field_genitive_case" => "номера" "field_nominative_case" => "номер" "field_prepositional_case" => "номере" ] "field_short_name" => "№" ] #original: array:6 [ "id" => 26 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "name" => "номер" "field_cases" => array:6 [ "field_accusative_case" => "номер" "field_creative_case" => "номером" "field_dative_case" => "номеру" "field_genitive_case" => "номера" "field_nominative_case" => "номер" "field_prepositional_case" => "номере" ] "field_short_name" => "№" ] #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 "field_match" => null "breadcrumbs" => [] "edition_groups" => Illuminate\Database\Eloquent\Collection {#1026 #items: [] #escapeWhenCastingToString: false } "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#342 #items: array:1 [ 0 => App\Models\Branch {#1023 #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" => 1433206 "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 {#333 #items: array:1 [ 0 => App\Models\Term {#1033 #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" => 31 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "name" => "Часть" "field_cases" => array:6 [ …6] "field_page_check_not_needed" => "1" "field_short_name" => "ч." ] #original: array:7 [ "id" => 31 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "name" => "Часть" "field_cases" => array:6 [ …6] "field_page_check_not_needed" => "1" "field_short_name" => "ч." ] #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_page_start" => "6" "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 {#1030 #items: array:1 [ 0 => App\Models\Book {#1032 #connection: "mysql" #table: "books" #primaryKey: "id" #keyType: "int" +incrementing: false #with: [] #withCount: [] +preventsLazyLoading: false #perPage: 15 +exists: true +wasRecentlyCreated: false #escapeWhenCastingToString: false #attributes: array:50 [ "id" => 2980 "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 {#1034 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1036 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1038 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1040 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1045 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1046 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1048 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1050 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1052 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1053 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1054 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1055 …2} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1056 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1057 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2016" "field_publication_year_until" => null "field_part" => "1, 2" "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" => "1111" "field_priority" => null "field_default_folder" => "/fizika_09/gendenshtejn-u/" "field_isbn" => "978-5-9963-3062-1" "field_cover" => array:2 [ …2] "field_cover_alts" => array:2 [ …2] "field_covers" => array:2 [ …2] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1059 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1060 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1061 …2} "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1062 …2} "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "breadcrumbs" => array:3 [ …3] ] #original: array:50 [ "id" => 2980 "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 {#1034 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1036 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1038 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1040 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1045 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1046 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1048 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1050 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1052 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1053 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1054 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1055 …2} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1056 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1057 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2016" "field_publication_year_until" => null "field_part" => "1, 2" "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" => "1111" "field_priority" => null "field_default_folder" => "/fizika_09/gendenshtejn-u/" "field_isbn" => "978-5-9963-3062-1" "field_cover" => array:2 [ …2] "field_cover_alts" => array:2 [ …2] "field_covers" => array:2 [ …2] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1059 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1060 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1061 …2} "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1062 …2} "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "breadcrumbs" => array:3 [ …3] ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } ] #escapeWhenCastingToString: false } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1064 #items: [] #escapeWhenCastingToString: false } ] #original: array:24 [ "id" => 1433206 "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 {#333} "field_page_start" => "6" "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 {#1030} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1064} ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } ] #escapeWhenCastingToString: false } "parent_branches" => Illuminate\Database\Eloquent\Collection {#1065 #items: array:4 [ 0 => App\Models\Branch {#1023} 1 => App\Models\Branch {#1066 #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" => 1433207 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Механические явления" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1067 #items: [] #escapeWhenCastingToString: false } "field_page_start" => "6" "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 {#1068 #items: array:1 [ 0 => App\Models\Book {#1069 #connection: "mysql" #table: "books" #primaryKey: "id" #keyType: "int" +incrementing: false #with: [] #withCount: [] +preventsLazyLoading: false #perPage: 15 +exists: true +wasRecentlyCreated: false #escapeWhenCastingToString: false #attributes: array:50 [ "id" => 2980 "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 {#1070 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1072 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1074 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1076 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1081 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1082 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1084 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1086 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1088 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1089 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1090 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1091 …2} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1092 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1093 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2016" "field_publication_year_until" => null "field_part" => "1, 2" "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" => "1111" "field_priority" => null "field_default_folder" => "/fizika_09/gendenshtejn-u/" "field_isbn" => "978-5-9963-3062-1" "field_cover" => array:2 [ …2] "field_cover_alts" => array:2 [ …2] "field_covers" => array:2 [ …2] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1095 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1096 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1097 …2} "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1098 …2} "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "breadcrumbs" => array:3 [ …3] ] #original: array:50 [ "id" => 2980 "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 {#1070 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1072 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1074 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1076 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1081 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1082 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1084 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1086 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1088 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1089 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1090 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1091 …2} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1092 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1093 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2016" "field_publication_year_until" => null "field_part" => "1, 2" "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" => "1111" "field_priority" => null "field_default_folder" => "/fizika_09/gendenshtejn-u/" "field_isbn" => "978-5-9963-3062-1" "field_cover" => array:2 [ …2] "field_cover_alts" => array:2 [ …2] "field_covers" => array:2 [ …2] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1095 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1096 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1097 …2} "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1098 …2} "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "breadcrumbs" => array:3 [ …3] ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } ] #escapeWhenCastingToString: false } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1100 #items: array:1 [ 0 => App\Models\Branch {#1101 #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" => 1433206 "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 {#1102 …2} "field_page_start" => "6" "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 {#1104 …2} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1105 …2} ] #original: array:24 [ "id" => 1433206 "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 {#1102 …2} "field_page_start" => "6" "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 {#1104 …2} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1105 …2} ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } ] #escapeWhenCastingToString: false } ] #original: array:24 [ "id" => 1433207 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Механические явления" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1067} "field_page_start" => "6" "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 {#1068} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1100} ] #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\Branch {#1106 #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" => 1433214 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Динамика" "field_branch_order" => "II" "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1107 #items: array:1 [ 0 => App\Models\Term {#1108 #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" => 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 ] #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_page_start" => "59" "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 {#1109 #items: array:1 [ 0 => App\Models\Book {#1110 #connection: "mysql" #table: "books" #primaryKey: "id" #keyType: "int" +incrementing: false #with: [] #withCount: [] +preventsLazyLoading: false #perPage: 15 +exists: true +wasRecentlyCreated: false #escapeWhenCastingToString: false #attributes: array:50 [ "id" => 2980 "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 {#1111 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1113 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1115 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1117 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1122 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1123 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1125 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1127 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1129 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1130 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1131 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1132 …2} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1133 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1134 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2016" "field_publication_year_until" => null "field_part" => "1, 2" "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" => "1111" "field_priority" => null "field_default_folder" => "/fizika_09/gendenshtejn-u/" "field_isbn" => "978-5-9963-3062-1" "field_cover" => array:2 [ …2] "field_cover_alts" => array:2 [ …2] "field_covers" => array:2 [ …2] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1136 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1137 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1138 …2} "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1139 …2} "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "breadcrumbs" => array:3 [ …3] ] #original: array:50 [ "id" => 2980 "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 {#1111 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1113 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1115 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1117 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1122 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1123 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1125 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1127 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1129 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1130 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1131 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1132 …2} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1133 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1134 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2016" "field_publication_year_until" => null "field_part" => "1, 2" "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" => "1111" "field_priority" => null "field_default_folder" => "/fizika_09/gendenshtejn-u/" "field_isbn" => "978-5-9963-3062-1" "field_cover" => array:2 [ …2] "field_cover_alts" => array:2 [ …2] "field_covers" => array:2 [ …2] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1136 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1137 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1138 …2} "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1139 …2} "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "breadcrumbs" => array:3 [ …3] ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } ] #escapeWhenCastingToString: false } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1141 #items: array:1 [ 0 => App\Models\Branch {#1142 #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" => 1433207 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Механические явления" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1143 …2} "field_page_start" => "6" "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 {#1144 …2} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1176 …2} ] #original: array:24 [ "id" => 1433207 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Механические явления" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1143 …2} "field_page_start" => "6" "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 {#1144 …2} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1176 …2} ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } ] #escapeWhenCastingToString: false } ] #original: array:24 [ "id" => 1433214 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Динамика" "field_branch_order" => "II" "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1107} "field_page_start" => "59" "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 {#1109} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1141} ] #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\Branch {#1213 #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" => 1433220 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Силы трения" "field_branch_order" => "11" "field_url" => null "field_branch_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: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: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } ] #escapeWhenCastingToString: false } "field_page_start" => "96" "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 {#1216 #items: array:1 [ 0 => App\Models\Book {#1217 #connection: "mysql" #table: "books" #primaryKey: "id" #keyType: "int" +incrementing: false #with: [] #withCount: [] +preventsLazyLoading: false #perPage: 15 +exists: true +wasRecentlyCreated: false #escapeWhenCastingToString: false #attributes: array:50 [ "id" => 2980 "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 {#1218 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1220 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1222 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1224 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1229 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1230 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1232 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1234 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1236 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1237 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1238 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1239 …2} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1240 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1241 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2016" "field_publication_year_until" => null "field_part" => "1, 2" "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" => "1111" "field_priority" => null "field_default_folder" => "/fizika_09/gendenshtejn-u/" "field_isbn" => "978-5-9963-3062-1" "field_cover" => array:2 [ …2] "field_cover_alts" => array:2 [ …2] "field_covers" => array:2 [ …2] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1243 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1244 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1245 …2} "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1246 …2} "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "breadcrumbs" => array:3 [ …3] ] #original: array:50 [ "id" => 2980 "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 {#1218 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1220 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1222 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1224 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1229 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1230 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1232 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1234 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1236 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1237 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1238 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1239 …2} "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1240 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1241 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2016" "field_publication_year_until" => null "field_part" => "1, 2" "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" => "1111" "field_priority" => null "field_default_folder" => "/fizika_09/gendenshtejn-u/" "field_isbn" => "978-5-9963-3062-1" "field_cover" => array:2 [ …2] "field_cover_alts" => array:2 [ …2] "field_covers" => array:2 [ …2] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1243 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1244 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1245 …2} "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1246 …2} "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "breadcrumbs" => array:3 [ …3] ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } ] #escapeWhenCastingToString: false } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1248 #items: array:1 [ 0 => App\Models\Branch {#1249 #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" => 1433214 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Динамика" "field_branch_order" => "II" "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1250 …2} "field_page_start" => "59" "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 {#1252 …2} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1284 …2} ] #original: array:24 [ "id" => 1433214 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Динамика" "field_branch_order" => "II" "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1250 …2} "field_page_start" => "59" "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 {#1252 …2} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1284 …2} ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } ] #original: array:24 [ "id" => 1433220 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Силы трения" "field_branch_order" => "11" "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1214} "field_page_start" => "96" "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 {#1216} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1248} ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } ] #escapeWhenCastingToString: false } "content" => Illuminate\Database\Eloquent\Collection {#1294 #items: array:2 [ 0 => App\Models\Element {#1295 #connection: "mysql" #table: "elements" #primaryKey: "id" #keyType: "int" +incrementing: true #with: [] #withCount: [] +preventsLazyLoading: false #perPage: 15 +exists: true +wasRecentlyCreated: false #escapeWhenCastingToString: false #attributes: array:7 [ "id" => 1696384 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1296 #items: array:1 [ 0 => App\Models\Edition {#1297 #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 [ …21] #original: array:21 [ …21] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "task" => array:2 [ "refs" => "1433643" "type" => "task" ] "text" => "<p><strong>28.</strong> С какой скоростью можно ехать в густом тумане, когда видимость равна 20 м? Коэффициент трения между шинами и мокрым асфальтом примите равным 0,25.</p>" "img" => array:1 [ 0 => array:5 [ "name" => "28-1.jpg" "alt" => null "width" => "1593" "height" => 250 "path" => "/media/fizika_09/gendenshtejn-u/0-11/28-1.webp?ts=1759348238" ] ] ] #original: array:7 [ "id" => 1696384 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1296} "task" => array:2 [ "refs" => "1433643" "type" => "task" ] "text" => "<p><strong>28.</strong> С какой скоростью можно ехать в густом тумане, когда видимость равна 20 м? Коэффициент трения между шинами и мокрым асфальтом примите равным 0,25.</p>" "img" => array:1 [ 0 => array:5 [ "name" => "28-1.jpg" "alt" => null "width" => "1593" "height" => 250 "path" => "/media/fizika_09/gendenshtejn-u/0-11/28-1.webp?ts=1759348238" ] ] ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } 1 => App\Models\Element {#1303 #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" => 1780454 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1304 #items: array:1 [ 0 => App\Models\Edition {#1305 #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 [ …21] #original: array:21 [ …21] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "task" => array:2 [ "refs" => "1433643" "type" => "task" ] "text" => "<p><strong>Дано:</strong></p><p>Дальность видимости, $S = 20$ м</p><p>Коэффициент трения, $\mu = 0.25$</p><p>Ускорение свободного падения, $g \approx 10$ м/с² (принимаем для удобства расчетов)</p><p>Все величины представлены в системе СИ.</p><p><strong>Найти:</strong></p><p>Максимально допустимую скорость, $\text{v}$ - ?</p><p><strong>Решение:</strong></p><p>Для безопасного движения в условиях ограниченной видимости необходимо, чтобы тормозной путь автомобиля $S_{торм}$ не превышал дальность видимости $\text{S}$. В предельном случае, чтобы найти максимальную скорость, мы приравниваем тормозной путь к дальности видимости:</p><p>$S_{торм} = S$</p><p>При торможении на автомобиль действует сила трения, которая сообщает ему отрицательное ускорение (замедление). Согласно второму закону Ньютона:</p><p>$F_{тр} = m \cdot a$</p><p>где $\text{m}$ – масса автомобиля, $\text{a}$ – его ускорение.</p><p>Сила трения скольжения определяется как:</p><p>$F_{тр} = \mu \cdot N$</p><p>где $\text{N}$ – сила нормальной реакции опоры. На горизонтальной дороге $\text{N}$ равна силе тяжести $mg$.</p><p>$N = mg$</p><p>Следовательно, $F_{тр} = \mu mg$.</p><p>Приравнивая выражения для силы трения, находим ускорение:</p><p>$\mu mg = ma$</p><p>$a = \mu g$</p><p>Тормозной путь можно найти из формулы для равноускоренного движения без времени:</p><p>$S_{торм} = \frac{v_k^2 - v_0^2}{2a_{proj}}$</p><p>Здесь $v_0$ – начальная скорость (которую мы ищем, обозначим ее $\text{v}$), $v_k$ – конечная скорость ($v_k = 0$, так как автомобиль останавливается), $a_{proj}$ – проекция ускорения на ось движения. Так как ускорение направлено против движения, $a_{proj} = -a = -\mu g$.</p><p>$S = \frac{0^2 - v^2}{2(-\mu g)} = \frac{-v^2}{-2\mu g} = \frac{v^2}{2\mu g}$</p><p>Выразим из этой формулы искомую скорость $\text{v}$:</p><p>$v^2 = 2S\mu g$</p><p>$v = \sqrt{2S\mu g}$</p><p>Подставим числовые значения:</p><p>$v = \sqrt{2 \cdot 20 \text{ м} \cdot 0.25 \cdot 10 \frac{\text{м}}{\text{с}^2}} = \sqrt{100 \frac{\text{м}^2}{\text{с}^2}} = 10 \frac{\text{м}}{\text{с}}$</p><p>Для наглядности переведем скорость в километры в час:</p><p>$10 \frac{\text{м}}{\text{с}} \cdot 3.6 = 36 \frac{\text{км}}{\text{ч}}$</p><p><strong>Ответ:</strong> в густом тумане при данных условиях можно ехать со скоростью не более 10 м/с (или 36 км/ч).</p>" ] #original: array:6 [ "id" => 1780454 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1304} "task" => array:2 [ "refs" => "1433643" "type" => "task" ] "text" => "<p><strong>Дано:</strong></p><p>Дальность видимости, $S = 20$ м</p><p>Коэффициент трения, $\mu = 0.25$</p><p>Ускорение свободного падения, $g \approx 10$ м/с² (принимаем для удобства расчетов)</p><p>Все величины представлены в системе СИ.</p><p><strong>Найти:</strong></p><p>Максимально допустимую скорость, $\text{v}$ - ?</p><p><strong>Решение:</strong></p><p>Для безопасного движения в условиях ограниченной видимости необходимо, чтобы тормозной путь автомобиля $S_{торм}$ не превышал дальность видимости $\text{S}$. В предельном случае, чтобы найти максимальную скорость, мы приравниваем тормозной путь к дальности видимости:</p><p>$S_{торм} = S$</p><p>При торможении на автомобиль действует сила трения, которая сообщает ему отрицательное ускорение (замедление). Согласно второму закону Ньютона:</p><p>$F_{тр} = m \cdot a$</p><p>где $\text{m}$ – масса автомобиля, $\text{a}$ – его ускорение.</p><p>Сила трения скольжения определяется как:</p><p>$F_{тр} = \mu \cdot N$</p><p>где $\text{N}$ – сила нормальной реакции опоры. На горизонтальной дороге $\text{N}$ равна силе тяжести $mg$.</p><p>$N = mg$</p><p>Следовательно, $F_{тр} = \mu mg$.</p><p>Приравнивая выражения для силы трения, находим ускорение:</p><p>$\mu mg = ma$</p><p>$a = \mu g$</p><p>Тормозной путь можно найти из формулы для равноускоренного движения без времени:</p><p>$S_{торм} = \frac{v_k^2 - v_0^2}{2a_{proj}}$</p><p>Здесь $v_0$ – начальная скорость (которую мы ищем, обозначим ее $\text{v}$), $v_k$ – конечная скорость ($v_k = 0$, так как автомобиль останавливается), $a_{proj}$ – проекция ускорения на ось движения. Так как ускорение направлено против движения, $a_{proj} = -a = -\mu g$.</p><p>$S = \frac{0^2 - v^2}{2(-\mu g)} = \frac{-v^2}{-2\mu g} = \frac{v^2}{2\mu g}$</p><p>Выразим из этой формулы искомую скорость $\text{v}$:</p><p>$v^2 = 2S\mu g$</p><p>$v = \sqrt{2S\mu g}$</p><p>Подставим числовые значения:</p><p>$v = \sqrt{2 \cdot 20 \text{ м} \cdot 0.25 \cdot 10 \frac{\text{м}}{\text{с}^2}} = \sqrt{100 \frac{\text{м}^2}{\text{с}^2}} = 10 \frac{\text{м}}{\text{с}}$</p><p>Для наглядности переведем скорость в километры в час:</p><p>$10 \frac{\text{м}}{\text{с}} \cdot 3.6 = 36 \frac{\text{км}}{\text{ч}}$</p><p><strong>Ответ:</strong> в густом тумане при данных условиях можно ехать со скоростью не более 10 м/с (или 36 км/ч).</p>" ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } ] #escapeWhenCastingToString: false } "next" => array:2 [ "refs" => "1433644" "type" => "task" ] "previous" => array:2 [ "refs" => "1433642" "type" => "task" ] "book" => Illuminate\Database\Eloquent\Collection {#1311 #items: array:1 [ 0 => App\Models\Book {#1312 #connection: "mysql" #table: "books" #primaryKey: "id" #keyType: "int" +incrementing: false #with: [] #withCount: [] +preventsLazyLoading: false #perPage: 15 +exists: true +wasRecentlyCreated: false #escapeWhenCastingToString: false #attributes: array:50 [ "id" => 2980 "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 {#1313 #items: array:1 [ 0 => App\Models\Term {#1314 #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 [ …10] #original: array:10 [ …10] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "field_class" => Illuminate\Database\Eloquent\Collection {#1315 #items: array:1 [ 0 => App\Models\Term {#1316 #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 [ …6] #original: array:6 [ …6] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "field_publisher" => Illuminate\Database\Eloquent\Collection {#1317 #items: array:1 [ 0 => App\Models\Term {#1318 #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 [ …6] #original: array:6 [ …6] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "field_author" => Illuminate\Database\Eloquent\Collection {#1319 #items: array:4 [ 0 => App\Models\Term {#1320 #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 [ …12] #original: array:12 [ …12] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } 1 => App\Models\Term {#1321 #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 [ …12] #original: array:12 [ …12] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } 2 => App\Models\Term {#1322 #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 [ …12] #original: array:12 [ …12] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } 3 => App\Models\Term {#1323 #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 [ …12] #original: array:12 [ …12] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1324 #items: [] #escapeWhenCastingToString: false } "field_book_type" => Illuminate\Database\Eloquent\Collection {#1325 #items: array:1 [ 0 => App\Models\Term {#1326 #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 [ …10] #original: array:10 [ …10] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "field_country" => Illuminate\Database\Eloquent\Collection {#1327 #items: array:1 [ 0 => App\Models\Term {#1328 #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 [ …6] #original: array:6 [ …6] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "field_city" => Illuminate\Database\Eloquent\Collection {#1329 #items: array:1 [ 0 => App\Models\Term {#1330 #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 [ …6] #original: array:6 [ …6] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "field_series" => Illuminate\Database\Eloquent\Collection {#1331 #items: [] #escapeWhenCastingToString: false } "field_umk" => Illuminate\Database\Eloquent\Collection {#1332 #items: [] #escapeWhenCastingToString: false } "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1333 #items: [] #escapeWhenCastingToString: false } "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1334 #items: [] #escapeWhenCastingToString: false } "field_publication_number" => null "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1335 #items: [] #escapeWhenCastingToString: false } "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1336 #items: array:1 [ 0 => App\Models\Term {#1337 #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 [ …12] #original: array:12 [ …12] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2016" "field_publication_year_until" => null "field_part" => "1, 2" "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" => "1111" "field_priority" => null "field_default_folder" => "/fizika_09/gendenshtejn-u/" "field_isbn" => "978-5-9963-3062-1" "field_cover" => array:2 [ 0 => "/media/fizika_09/gendenshtejn-u/covers/cover1.webp?ts=1759256052" 1 => "/media/fizika_09/gendenshtejn-u/covers/cover2.webp?ts=1759256052" ] "field_cover_alts" => array:2 [ 0 => "" 1 => "" ] "field_covers" => array:2 [ 0 => array:4 [ "path" => "/media/fizika_09/gendenshtejn-u/covers/cover1.webp?ts=1759256052" "alt" => "" "width" => "1863" "height" => "2813" ] 1 => array:4 [ "path" => "/media/fizika_09/gendenshtejn-u/covers/cover2.webp?ts=1759256052" "alt" => "" "width" => "1863" "height" => "2809" ] ] "field_popular_book" => 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№28 (с. 105)
Условие. №28 (с. 105)
скриншот условия
28. С какой скоростью можно ехать в густом тумане, когда видимость равна 20 м? Коэффициент трения между шинами и мокрым асфальтом примите равным 0,25.
Решение. №28 (с. 105)
Дано:
Дальность видимости, $S = 20$ м
Коэффициент трения, $\mu = 0.25$
Ускорение свободного падения, $g \approx 10$ м/с² (принимаем для удобства расчетов)
Все величины представлены в системе СИ.
Найти:
Максимально допустимую скорость, $\text{v}$ - ?
Решение:
Для безопасного движения в условиях ограниченной видимости необходимо, чтобы тормозной путь автомобиля $S_{торм}$ не превышал дальность видимости $\text{S}$. В предельном случае, чтобы найти максимальную скорость, мы приравниваем тормозной путь к дальности видимости:
$S_{торм} = S$
При торможении на автомобиль действует сила трения, которая сообщает ему отрицательное ускорение (замедление). Согласно второму закону Ньютона:
$F_{тр} = m \cdot a$
где $\text{m}$ – масса автомобиля, $\text{a}$ – его ускорение.
Сила трения скольжения определяется как:
$F_{тр} = \mu \cdot N$
где $\text{N}$ – сила нормальной реакции опоры. На горизонтальной дороге $\text{N}$ равна силе тяжести $mg$.
$N = mg$
Следовательно, $F_{тр} = \mu mg$.
Приравнивая выражения для силы трения, находим ускорение:
$\mu mg = ma$
$a = \mu g$
Тормозной путь можно найти из формулы для равноускоренного движения без времени:
$S_{торм} = \frac{v_k^2 - v_0^2}{2a_{proj}}$
Здесь $v_0$ – начальная скорость (которую мы ищем, обозначим ее $\text{v}$), $v_k$ – конечная скорость ($v_k = 0$, так как автомобиль останавливается), $a_{proj}$ – проекция ускорения на ось движения. Так как ускорение направлено против движения, $a_{proj} = -a = -\mu g$.
$S = \frac{0^2 - v^2}{2(-\mu g)} = \frac{-v^2}{-2\mu g} = \frac{v^2}{2\mu g}$
Выразим из этой формулы искомую скорость $\text{v}$:
$v^2 = 2S\mu g$
$v = \sqrt{2S\mu g}$
Подставим числовые значения:
$v = \sqrt{2 \cdot 20 \text{ м} \cdot 0.25 \cdot 10 \frac{\text{м}}{\text{с}^2}} = \sqrt{100 \frac{\text{м}^2}{\text{с}^2}} = 10 \frac{\text{м}}{\text{с}}$
Для наглядности переведем скорость в километры в час:
$10 \frac{\text{м}}{\text{с}} \cdot 3.6 = 36 \frac{\text{км}}{\text{ч}}$
Ответ: в густом тумане при данных условиях можно ехать со скоростью не более 10 м/с (или 36 км/ч).
Другие задания:
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