gdz.top
Номер 48, страница 11, часть 1 - гдз по физике 10-11 класс сборник задач Парфентьева
Авторы: Парфентьева Н. А.
Тип: Сборник задач
Серия: классический курс
Издательство: Просвещение
Год издания: 2007 - 2026
Часть: 1
Цвет обложки: фиолетовый
ISBN: 978-5-09-092936-3
Популярные ГДЗ в 10 классе
Часть 1. 10 класс. Механика. Кинематика. Кинематика точки. Сложение скоростей - номер 48, страница 11.
App\Models\Task {#1030 // 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" => 1320051 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "11" "field_page_end" => null "field_url" => "/10-klass/fizika/parfenteva-sbornik-zadach/1-48" "field_display_title" => "48" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1037 #items: array:1 [ 0 => App\Models\Term {#1036 #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 {#1035 #items: [] #escapeWhenCastingToString: false } "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1075 #items: array:1 [ 0 => App\Models\Branch {#1034 #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" => 1319883 "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 {#1039 #items: array:1 [ 0 => App\Models\Term {#1038 #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" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1040 #items: array:1 [ 0 => App\Models\Book {#1041 #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" => 3751 "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 {#1042 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1044 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1047 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1049 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1051 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1052 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1054 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1056 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1058 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1060 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1061 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1062 …2} "field_publication_number" => "13" "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1064 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1066 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2007" "field_publication_year_until" => null "field_part" => "" "field_part_writing" => "" "field_second_foreign_language" => null "field_for_whom" => "Учебное пособие" "field_allowed" => null "field_reserve_field" => null "field_link_to_source" => null "field_tasks_count" => "1110" "field_priority" => null "field_default_folder" => "/fizika_10/parfenteva-sz/" "field_isbn" => "978-5-09-092936-3" "field_cover" => array:1 [ …1] "field_cover_alts" => array:1 [ …1] "field_covers" => array:1 [ …1] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1067 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1068 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1069 …2} "field_url" => "/10-klass/fizika/parfenteva-sbornik-zadach" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1070 …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" => 3751 "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 {#1042 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1044 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1047 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1049 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1051 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1052 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1054 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1056 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1058 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1060 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1061 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1062 …2} "field_publication_number" => "13" "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1064 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1066 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2007" "field_publication_year_until" => null "field_part" => "" "field_part_writing" => "" "field_second_foreign_language" => null "field_for_whom" => "Учебное пособие" "field_allowed" => null "field_reserve_field" => null "field_link_to_source" => null "field_tasks_count" => "1110" "field_priority" => null "field_default_folder" => "/fizika_10/parfenteva-sz/" "field_isbn" => "978-5-09-092936-3" "field_cover" => array:1 [ …1] "field_cover_alts" => array:1 [ …1] "field_covers" => array:1 [ …1] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1067 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1068 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1069 …2} "field_url" => "/10-klass/fizika/parfenteva-sbornik-zadach" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1070 …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 {#1072 #items: [] #escapeWhenCastingToString: false } ] #original: array:24 [ "id" => 1319883 "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 {#1039} "field_page_start" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1040} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1072} ] #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 {#1412 #items: array:6 [ 0 => App\Models\Branch {#1073 #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" => 1319883 "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 {#1076 #items: array:1 [ 0 => App\Models\Term {#1074 #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" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1077 #items: array:1 [ 0 => App\Models\Book {#1078 #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" => 3751 "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 {#1079 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1081 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1084 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1086 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1088 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1089 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1091 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1093 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1095 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1097 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1098 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1099 …2} "field_publication_number" => "13" "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1101 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1103 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2007" "field_publication_year_until" => null "field_part" => "" "field_part_writing" => "" "field_second_foreign_language" => null "field_for_whom" => "Учебное пособие" "field_allowed" => null "field_reserve_field" => null "field_link_to_source" => null "field_tasks_count" => "1110" "field_priority" => null "field_default_folder" => "/fizika_10/parfenteva-sz/" "field_isbn" => "978-5-09-092936-3" "field_cover" => array:1 [ …1] "field_cover_alts" => array:1 [ …1] "field_covers" => array:1 [ …1] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1104 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1105 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1106 …2} "field_url" => "/10-klass/fizika/parfenteva-sbornik-zadach" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1107 …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" => 3751 "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 {#1079 …2} "field_class" => Illuminate\Database\Eloquent\Collection {#1081 …2} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1084 …2} "field_author" => Illuminate\Database\Eloquent\Collection {#1086 …2} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1088 …2} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1089 …2} "field_country" => Illuminate\Database\Eloquent\Collection {#1091 …2} "field_city" => Illuminate\Database\Eloquent\Collection {#1093 …2} "field_series" => Illuminate\Database\Eloquent\Collection {#1095 …2} "field_umk" => Illuminate\Database\Eloquent\Collection {#1097 …2} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1098 …2} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1099 …2} "field_publication_number" => "13" "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1101 …2} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1103 …2} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2007" "field_publication_year_until" => null "field_part" => "" "field_part_writing" => "" "field_second_foreign_language" => null "field_for_whom" => "Учебное пособие" "field_allowed" => null "field_reserve_field" => null "field_link_to_source" => null "field_tasks_count" => "1110" "field_priority" => null "field_default_folder" => "/fizika_10/parfenteva-sz/" "field_isbn" => "978-5-09-092936-3" "field_cover" => array:1 [ …1] "field_cover_alts" => array:1 [ …1] "field_covers" => array:1 [ …1] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1104 …2} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1105 …2} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1106 …2} "field_url" => "/10-klass/fizika/parfenteva-sbornik-zadach" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1107 …2} "field_metatags_title" => null "field_metatags_description" => null …4 ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1109 #items: [] #escapeWhenCastingToString: false } ] #original: array:24 [ "id" => 1319883 "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 {#1076} "field_page_start" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1077} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1109} ] #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\Branch {#1110 #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" => 1319884 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "10 класс" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1111 #items: [] #escapeWhenCastingToString: false } "field_page_start" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1112 #items: array:1 [ 0 => App\Models\Book {#1113 #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 [ …50] #original: array:50 [ …50] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1144 #items: array:1 [ 0 => App\Models\Branch {#1145 #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 [ …24] #original: array:24 [ …24] #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" => 1319884 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "10 класс" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1111} "field_page_start" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1112} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1144} ] #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 {#1150 #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" => 1319885 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Механика" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1151 #items: [] #escapeWhenCastingToString: false } "field_page_start" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1152 #items: array:1 [ 0 => App\Models\Book {#1153 #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 [ …50] #original: array:50 [ …50] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1184 #items: array:1 [ 0 => App\Models\Branch {#1185 #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 [ …24] #original: array:24 [ …24] #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" => 1319885 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Механика" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1151} "field_page_start" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1152} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1184} ] #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 {#1194 #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" => 1319886 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Кинематика" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1195 #items: [] #escapeWhenCastingToString: false } "field_page_start" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1196 #items: array:1 [ 0 => App\Models\Book {#1197 #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 [ …50] #original: array:50 [ …50] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1228 #items: array:1 [ 0 => App\Models\Branch {#1229 #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 [ …24] #original: array:24 [ …24] #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" => 1319886 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Кинематика" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1195} "field_page_start" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1196} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1228} ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } 4 => App\Models\Branch {#1242 #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" => 1319887 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Кинематика точки" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1243 #items: [] #escapeWhenCastingToString: false } "field_page_start" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1244 #items: array:1 [ 0 => App\Models\Book {#1245 #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 [ …50] #original: array:50 [ …50] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1276 #items: array:1 [ 0 => App\Models\Branch {#1277 #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 [ …24] #original: array:24 [ …24] #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" => 1319887 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Кинематика точки" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1243} "field_page_start" => "5" "field_branch_display" => "0" "field_branch_expanded" => "0" "field_display_branch_in_title" => "1" "field_display_task_interval" => "0" "field_display_branch_page" => "1" "field_branch_title_in_content" => "0" "field_navigation_title" => null "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "field_branch_cover" => [] "field_branch_covers" => [] "book" => Illuminate\Database\Eloquent\Collection {#1244} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1276} ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } 5 => App\Models\Branch {#1325 #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" => 1319891 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Сложение скоростей" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1326 #items: [] #escapeWhenCastingToString: false } "field_page_start" => "9" "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 {#1327 #items: array:1 [ 0 => App\Models\Book {#1328 #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 [ …50] #original: array:50 [ …50] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } ] #escapeWhenCastingToString: false } "branch_parent" => Illuminate\Database\Eloquent\Collection {#1359 #items: array:1 [ 0 => App\Models\Branch {#1360 #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 [ …24] #original: array:24 [ …24] #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" => 1319891 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_display_title" => "Сложение скоростей" "field_branch_order" => null "field_url" => null "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1326} "field_page_start" => "9" "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 {#1327} "branch_parent" => Illuminate\Database\Eloquent\Collection {#1359} ] #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 {#1413 #items: array:2 [ 0 => App\Models\Element {#1423 #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" => 1496209 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1432 #items: array:1 [ 0 => App\Models\Edition {#1424 #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" => "1320051" "type" => "task" ] "text" => "<p><strong>48.</strong> По шоссе со скоростью 10 м/с едет автобус. Человек находится на расстоянии 100 м от шоссе и 300 м от автобуса. В каком направлении должен идти человек, чтобы выйти на шоссе раньше автобуса или одновременно с ним? Скорость человека 5 м/с.</p>" "img" => array:1 [ 0 => array:5 [ "name" => "48-1.jpg" "alt" => null "width" => "1377" "height" => 305 "path" => "/media/fizika_10/parfenteva-sz/0-1/48-1.webp?ts=1756373041" ] ] ] #original: array:7 [ "id" => 1496209 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1432} "task" => array:2 [ "refs" => "1320051" "type" => "task" ] "text" => "<p><strong>48.</strong> По шоссе со скоростью 10 м/с едет автобус. Человек находится на расстоянии 100 м от шоссе и 300 м от автобуса. В каком направлении должен идти человек, чтобы выйти на шоссе раньше автобуса или одновременно с ним? Скорость человека 5 м/с.</p>" "img" => array:1 [ 0 => array:5 [ "name" => "48-1.jpg" "alt" => null "width" => "1377" "height" => 305 "path" => "/media/fizika_10/parfenteva-sz/0-1/48-1.webp?ts=1756373041" ] ] ] #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 {#1430 #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" => 1724136 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1440 #items: array:1 [ 0 => App\Models\Edition {#1431 #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" => "1320051" "type" => "task" ] "text" => "<p><strong>Дано:</strong></p><p>Скорость автобуса $v_а = 10$ м/с<br>Скорость человека $v_ч = 5$ м/с<br>Расстояние от человека до шоссе $h = 100$ м<br>Расстояние от человека до автобуса $D = 300$ м</p><p>Все данные представлены в системе СИ.</p><p><strong>Найти:</strong></p><p>Направление, в котором должен идти человек.</p><p><strong>Решение:</strong></p><p>Введем систему координат. Пусть шоссе совпадает с осью Ox, а перпендикуляр, опущенный из точки нахождения человека на шоссе, совпадает с осью Oy. Тогда человек находится в точке P с координатами $(0, h)$, то есть P(0, 100 м).</p><p>Автобус B находится на шоссе (ось Ox). Расстояние от человека до автобуса $D=PB=300$ м. Точка O(0,0) — это проекция положения человека на шоссе. Рассмотрим прямоугольный треугольник POB. По теореме Пифагора найдем расстояние OB — начальное расстояние по шоссе от автобуса до ближайшей к человеку точки на шоссе:</p><p>$OB = \sqrt{PB^2 - PO^2} = \sqrt{D^2 - h^2} = \sqrt{300^2 - 100^2} = \sqrt{90000 - 10000} = \sqrt{80000} = 200\sqrt{2}$ м.</p><p>Скорость автобуса ($10$ м/с) больше скорости человека ($\text{5}$ м/с). Человек сможет выйти на шоссе раньше автобуса или одновременно с ним только в том случае, если автобус движется ему навстречу (в сторону точки O). Таким образом, начальная координата автобуса B будет $(-200\sqrt{2}, 0)$, и он движется в положительном направлении оси Ox.</p><p>Пусть человек и автобус встречаются в точке M на шоссе с координатой $(x, 0)$. Человек должен выбрать такое $\text{x}$, чтобы его время в пути $t_ч$ было меньше или равно времени в пути автобуса $t_а$.</p><p>Время движения человека до точки M:</p><p>$t_ч = \frac{\text{расстояние PM}}{v_ч} = \frac{\sqrt{(x-0)^2 + (100-0)^2}}{5} = \frac{\sqrt{x^2 + 10000}}{5}$</p><p>Время движения автобуса до точки M:</p><p>$t_а = \frac{\text{расстояние BM}}{v_а} = \frac{x - (-200\sqrt{2})}{10} = \frac{x + 200\sqrt{2}}{10}$</p><p>Условие задачи: $t_ч \le t_а$.</p><p>$\frac{\sqrt{x^2 + 10000}}{5} \le \frac{x + 200\sqrt{2}}{10}$</p><p>Умножим обе части на 10:</p><p>$2\sqrt{x^2 + 10000} \le x + 200\sqrt{2}$</p><p>Левая часть неравенства всегда неотрицательна, значит и правая должна быть такой же. Возведем обе части в квадрат:</p><p>$4(x^2 + 10000) \le (x + 200\sqrt{2})^2$</p><p>$4x^2 + 40000 \le x^2 + 400\sqrt{2}x + 80000$</p><p>$3x^2 - 400\sqrt{2}x - 40000 \le 0$</p><p>Для решения этого квадратного неравенства найдем корни соответствующего уравнения $3x^2 - 400\sqrt{2}x - 40000 = 0$:</p><p>Дискриминант $D_k = (b/2)^2 - ac = (-200\sqrt{2})^2 - 3(-40000) = 80000 + 120000 = 200000$.</p><p>Корни уравнения:</p><p>$x_{1,2} = \frac{-b/2 \pm \sqrt{D_k}}{a} = \frac{200\sqrt{2} \pm \sqrt{200000}}{3} = \frac{200\sqrt{2} \pm 200\sqrt{5}}{3} = \frac{200}{3}(\sqrt{2} \pm \sqrt{5})$</p><p>Парабола $y=3x^2 - 400\sqrt{2}x - 40000$ имеет ветви, направленные вверх, поэтому неравенство выполняется между корнями:</p><p>$\frac{200}{3}(\sqrt{2} - \sqrt{5}) \le x \le \frac{200}{3}(\sqrt{2} + \sqrt{5})$</p><p>Это диапазон координат на шоссе, в которые должен целиться человек. Направление его движения можно охарактеризовать углом $\alpha$ между его траекторией (отрезок PM) и перпендикуляром к шоссе (отрезок PO).</p><p>Из прямоугольного треугольника POM имеем: $\tan(\alpha) = \frac{OM}{PO} = \frac{x}{100}$.</p><p>Найдем диапазон для $\tan(\alpha)$:</p><p>$\frac{1}{100} \cdot \frac{200}{3}(\sqrt{2} - \sqrt{5}) \le \tan(\alpha) \le \frac{1}{100} \cdot \frac{200}{3}(\sqrt{2} + \sqrt{5})$</p><p>$\frac{2}{3}(\sqrt{2} - \sqrt{5}) \le \tan(\alpha) \le \frac{2}{3}(\sqrt{2} + \sqrt{5})$</p><p>Приближенные значения: $\sqrt{2} \approx 1.414$, $\sqrt{5} \approx 2.236$.</p><p>$\tan(\alpha_{min}) \approx \frac{2}{3}(1.414 - 2.236) \approx -0.548 \implies \alpha_{min} \approx -28.7^\circ$</p><p>$\tan(\alpha_{max}) \approx \frac{2}{3}(1.414 + 2.236) \approx 2.433 \implies \alpha_{max} \approx 67.7^\circ$</p><p>Угол $\alpha$ отсчитывается от перпендикуляра к шоссе. Положительные значения угла соответствуют направлению в сторону движения автобуса, а отрицательные — в противоположную.</p><p><strong>Ответ:</strong></p><p>Человек должен идти в направлении, составляющем с перпендикуляром к шоссе угол $\alpha$ в диапазоне от $\arctan\left(\frac{2}{3}(\sqrt{2} - \sqrt{5})\right)$ до $\arctan\left(\frac{2}{3}(\sqrt{2} + \sqrt{5})\right)$. Приблизительно это составляет сектор от $-28.7^\circ$ до $67.7^\circ$, где положительный угол отсчитывается от перпендикуляра к шоссе в сторону движения автобуса.</p>" ] #original: array:6 [ "id" => 1724136 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "edition" => Illuminate\Database\Eloquent\Collection {#1440} "task" => array:2 [ "refs" => "1320051" "type" => "task" ] "text" => "<p><strong>Дано:</strong></p><p>Скорость автобуса $v_а = 10$ м/с<br>Скорость человека $v_ч = 5$ м/с<br>Расстояние от человека до шоссе $h = 100$ м<br>Расстояние от человека до автобуса $D = 300$ м</p><p>Все данные представлены в системе СИ.</p><p><strong>Найти:</strong></p><p>Направление, в котором должен идти человек.</p><p><strong>Решение:</strong></p><p>Введем систему координат. Пусть шоссе совпадает с осью Ox, а перпендикуляр, опущенный из точки нахождения человека на шоссе, совпадает с осью Oy. Тогда человек находится в точке P с координатами $(0, h)$, то есть P(0, 100 м).</p><p>Автобус B находится на шоссе (ось Ox). Расстояние от человека до автобуса $D=PB=300$ м. Точка O(0,0) — это проекция положения человека на шоссе. Рассмотрим прямоугольный треугольник POB. По теореме Пифагора найдем расстояние OB — начальное расстояние по шоссе от автобуса до ближайшей к человеку точки на шоссе:</p><p>$OB = \sqrt{PB^2 - PO^2} = \sqrt{D^2 - h^2} = \sqrt{300^2 - 100^2} = \sqrt{90000 - 10000} = \sqrt{80000} = 200\sqrt{2}$ м.</p><p>Скорость автобуса ($10$ м/с) больше скорости человека ($\text{5}$ м/с). Человек сможет выйти на шоссе раньше автобуса или одновременно с ним только в том случае, если автобус движется ему навстречу (в сторону точки O). Таким образом, начальная координата автобуса B будет $(-200\sqrt{2}, 0)$, и он движется в положительном направлении оси Ox.</p><p>Пусть человек и автобус встречаются в точке M на шоссе с координатой $(x, 0)$. Человек должен выбрать такое $\text{x}$, чтобы его время в пути $t_ч$ было меньше или равно времени в пути автобуса $t_а$.</p><p>Время движения человека до точки M:</p><p>$t_ч = \frac{\text{расстояние PM}}{v_ч} = \frac{\sqrt{(x-0)^2 + (100-0)^2}}{5} = \frac{\sqrt{x^2 + 10000}}{5}$</p><p>Время движения автобуса до точки M:</p><p>$t_а = \frac{\text{расстояние BM}}{v_а} = \frac{x - (-200\sqrt{2})}{10} = \frac{x + 200\sqrt{2}}{10}$</p><p>Условие задачи: $t_ч \le t_а$.</p><p>$\frac{\sqrt{x^2 + 10000}}{5} \le \frac{x + 200\sqrt{2}}{10}$</p><p>Умножим обе части на 10:</p><p>$2\sqrt{x^2 + 10000} \le x + 200\sqrt{2}$</p><p>Левая часть неравенства всегда неотрицательна, значит и правая должна быть такой же. Возведем обе части в квадрат:</p><p>$4(x^2 + 10000) \le (x + 200\sqrt{2})^2$</p><p>$4x^2 + 40000 \le x^2 + 400\sqrt{2}x + 80000$</p><p>$3x^2 - 400\sqrt{2}x - 40000 \le 0$</p><p>Для решения этого квадратного неравенства найдем корни соответствующего уравнения $3x^2 - 400\sqrt{2}x - 40000 = 0$:</p><p>Дискриминант $D_k = (b/2)^2 - ac = (-200\sqrt{2})^2 - 3(-40000) = 80000 + 120000 = 200000$.</p><p>Корни уравнения:</p><p>$x_{1,2} = \frac{-b/2 \pm \sqrt{D_k}}{a} = \frac{200\sqrt{2} \pm \sqrt{200000}}{3} = \frac{200\sqrt{2} \pm 200\sqrt{5}}{3} = \frac{200}{3}(\sqrt{2} \pm \sqrt{5})$</p><p>Парабола $y=3x^2 - 400\sqrt{2}x - 40000$ имеет ветви, направленные вверх, поэтому неравенство выполняется между корнями:</p><p>$\frac{200}{3}(\sqrt{2} - \sqrt{5}) \le x \le \frac{200}{3}(\sqrt{2} + \sqrt{5})$</p><p>Это диапазон координат на шоссе, в которые должен целиться человек. Направление его движения можно охарактеризовать углом $\alpha$ между его траекторией (отрезок PM) и перпендикуляром к шоссе (отрезок PO).</p><p>Из прямоугольного треугольника POM имеем: $\tan(\alpha) = \frac{OM}{PO} = \frac{x}{100}$.</p><p>Найдем диапазон для $\tan(\alpha)$:</p><p>$\frac{1}{100} \cdot \frac{200}{3}(\sqrt{2} - \sqrt{5}) \le \tan(\alpha) \le \frac{1}{100} \cdot \frac{200}{3}(\sqrt{2} + \sqrt{5})$</p><p>$\frac{2}{3}(\sqrt{2} - \sqrt{5}) \le \tan(\alpha) \le \frac{2}{3}(\sqrt{2} + \sqrt{5})$</p><p>Приближенные значения: $\sqrt{2} \approx 1.414$, $\sqrt{5} \approx 2.236$.</p><p>$\tan(\alpha_{min}) \approx \frac{2}{3}(1.414 - 2.236) \approx -0.548 \implies \alpha_{min} \approx -28.7^\circ$</p><p>$\tan(\alpha_{max}) \approx \frac{2}{3}(1.414 + 2.236) \approx 2.433 \implies \alpha_{max} \approx 67.7^\circ$</p><p>Угол $\alpha$ отсчитывается от перпендикуляра к шоссе. Положительные значения угла соответствуют направлению в сторону движения автобуса, а отрицательные — в противоположную.</p><p><strong>Ответ:</strong></p><p>Человек должен идти в направлении, составляющем с перпендикуляром к шоссе угол $\alpha$ в диапазоне от $\arctan\left(\frac{2}{3}(\sqrt{2} - \sqrt{5})\right)$ до $\arctan\left(\frac{2}{3}(\sqrt{2} + \sqrt{5})\right)$. Приблизительно это составляет сектор от $-28.7^\circ$ до $67.7^\circ$, где положительный угол отсчитывается от перпендикуляра к шоссе в сторону движения автобуса.</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" => "1320052" "type" => "task" ] "previous" => array:2 [ "refs" => "1320050" "type" => "task" ] "book" => Illuminate\Database\Eloquent\Collection {#1464 #items: array:1 [ 0 => App\Models\Book {#1420 #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" => 3751 "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 {#1414 #items: array:1 [ 0 => App\Models\Term {#1415 #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 {#1422 #items: array:2 [ 0 => App\Models\Term {#1418 #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] } 1 => App\Models\Term {#1416 #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 {#1419 #items: array:1 [ 0 => App\Models\Term {#1417 #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 {#1438 #items: array:1 [ 0 => App\Models\Term {#1439 #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 {#1441 #items: [] #escapeWhenCastingToString: false } "field_book_type" => Illuminate\Database\Eloquent\Collection {#1442 #items: array:1 [ 0 => App\Models\Term {#1443 #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 {#1444 #items: array:1 [ 0 => App\Models\Term {#1445 #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 {#1446 #items: array:1 [ 0 => App\Models\Term {#1447 #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 {#1448 #items: array:1 [ 0 => App\Models\Term {#1449 #connection: "mysql" #table: "terms" #primaryKey: "id" #keyType: "int" +incrementing: false #with: [] #withCount: [] +preventsLazyLoading: false #perPage: 15 +exists: true +wasRecentlyCreated: false #escapeWhenCastingToString: false #attributes: array:8 [ …8] #original: array:8 [ …8] #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_umk" => Illuminate\Database\Eloquent\Collection {#1450 #items: [] #escapeWhenCastingToString: false } "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1451 #items: [] #escapeWhenCastingToString: false } "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1452 #items: array:1 [ 0 => App\Models\Term {#1453 #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_publication_number" => "13" "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1454 #items: array:1 [ 0 => App\Models\Term {#1455 #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_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1456 #items: [] #escapeWhenCastingToString: false } "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2007" "field_publication_year_until" => null "field_part" => "" "field_part_writing" => "" "field_second_foreign_language" => null "field_for_whom" => "Учебное пособие" "field_allowed" => null "field_reserve_field" => null "field_link_to_source" => null "field_tasks_count" => "1110" "field_priority" => null "field_default_folder" => "/fizika_10/parfenteva-sz/" "field_isbn" => "978-5-09-092936-3" "field_cover" => array:1 [ 0 => "/media/fizika_10/parfenteva-sz/covers/cover1.webp?ts=1756251235" ] "field_cover_alts" => array:1 [ 0 => "" ] "field_covers" => array:1 [ 0 => array:4 [ "path" => "/media/fizika_10/parfenteva-sz/covers/cover1.webp?ts=1756251235" "alt" => "" "width" => "1588" "height" => "2426" ] ] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1457 #items: [] #escapeWhenCastingToString: false } "field_new_book" => Illuminate\Database\Eloquent\Collection {#1458 #items: [] #escapeWhenCastingToString: false } "field_old_book" => Illuminate\Database\Eloquent\Collection {#1459 #items: [] #escapeWhenCastingToString: false } "field_url" => "/10-klass/fizika/parfenteva-sbornik-zadach" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1460 #items: array:1 [ 0 => App\Models\Term {#1461 #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_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "breadcrumbs" => array:3 [ "class" => 381 "subject" => 556 "class_subject" => 494 ] ] #original: array:50 [ "id" => 3751 "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 {#1414} "field_class" => Illuminate\Database\Eloquent\Collection {#1422} "field_publisher" => Illuminate\Database\Eloquent\Collection {#1419} "field_author" => Illuminate\Database\Eloquent\Collection {#1438} "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1441} "field_book_type" => Illuminate\Database\Eloquent\Collection {#1442} "field_country" => Illuminate\Database\Eloquent\Collection {#1444} "field_city" => Illuminate\Database\Eloquent\Collection {#1446} "field_series" => Illuminate\Database\Eloquent\Collection {#1448} "field_umk" => Illuminate\Database\Eloquent\Collection {#1450} "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1451} "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1452} "field_publication_number" => "13" "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1454} "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1456} "field_under_the_edition_degree" => null "field_cover_description" => null "field_publication_year" => "2007" "field_publication_year_until" => null "field_part" => "" "field_part_writing" => "" "field_second_foreign_language" => null "field_for_whom" => "Учебное пособие" "field_allowed" => null "field_reserve_field" => null "field_link_to_source" => null "field_tasks_count" => "1110" "field_priority" => null "field_default_folder" => "/fizika_10/parfenteva-sz/" "field_isbn" => "978-5-09-092936-3" "field_cover" => array:1 [ 0 => "/media/fizika_10/parfenteva-sz/covers/cover1.webp?ts=1756251235" ] "field_cover_alts" => array:1 [ 0 => "" ] "field_covers" => array:1 [ 0 => array:4 [ "path" => "/media/fizika_10/parfenteva-sz/covers/cover1.webp?ts=1756251235" "alt" => "" "width" => "1588" "height" => "2426" ] ] "field_popular_book" => "0" "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1457} "field_new_book" => Illuminate\Database\Eloquent\Collection {#1458} "field_old_book" => Illuminate\Database\Eloquent\Collection {#1459} "field_url" => "/10-klass/fizika/parfenteva-sbornik-zadach" "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1460} "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "breadcrumbs" => array:3 [ "class" => 381 "subject" => 556 "class_subject" => 494 ] ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] } ] #escapeWhenCastingToString: false } "page" => Illuminate\Database\Eloquent\Collection {#1469 #items: array:1 [ 0 => App\Models\BookPage {#1468 #connection: "mysql" #table: "book_pages" #primaryKey: "id" #keyType: "int" +incrementing: true #with: [] #withCount: [] +preventsLazyLoading: false #perPage: 15 +exists: true +wasRecentlyCreated: false #escapeWhenCastingToString: false #attributes: array:21 [ "id" => 1341261 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "11" "field_url" => "/10-klass/fizika/parfenteva-sbornik-zadach/page-11" "field_display_title" => "11" "field_folder" => "1" "field_image_name" => "11" "field_branch_parent" => Illuminate\Database\Eloquent\Collection {#1470 #items: [] #escapeWhenCastingToString: false } "field_weight" => "0" "field_book_parent" => Illuminate\Database\Eloquent\Collection {#1471 #items: array:1 [ 0 => App\Models\Book {#1420} ] #escapeWhenCastingToString: false } "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "edition_groups" => Illuminate\Database\Eloquent\Collection {#1472 #items: [] #escapeWhenCastingToString: false } "content" => Illuminate\Database\Eloquent\Collection {#1483 #items: array:1 [ 0 => App\Models\Element {#1473 #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 [ …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 } "next" => array:2 [ "refs" => "1341262" "type" => "book_page" ] "previous" => array:2 [ "refs" => "1341260" "type" => "book_page" ] "tasks" => Illuminate\Database\Eloquent\Collection {#1913 #items: array:8 [ 0 => App\Models\Task {#1927 #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 [ …24] #original: array:24 [ …24] #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\Task {#1949 #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 [ …24] #original: array:24 [ …24] #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\Task {#1972 #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 [ …24] #original: array:24 [ …24] #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\Task {#1980 #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 [ …24] #original: array:24 [ …24] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } 4 => App\Models\Task {#2229 #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 [ …24] #original: array:24 [ …24] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } 5 => App\Models\Task {#2220 #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 [ …24] #original: array:24 [ …24] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } 6 => App\Models\Task {#2210 #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 [ …24] #original: array:24 [ …24] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ …1] } 7 => App\Models\Task {#2183 #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 [ …24] #original: array:24 [ …24] #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:21 [ "id" => 1341261 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "11" "field_url" => "/10-klass/fizika/parfenteva-sbornik-zadach/page-11" "field_display_title" => "11" "field_folder" => "1" "field_image_name" => "11" "field_branch_parent" => Illuminate\Database\Eloquent\Collection {#1470} "field_weight" => "0" "field_book_parent" => Illuminate\Database\Eloquent\Collection {#1471} "field_metatags_title" => null "field_metatags_description" => null "field_h1" => null "field_description_top" => null "field_description_bottom" => null "edition_groups" => Illuminate\Database\Eloquent\Collection {#1472} "content" => Illuminate\Database\Eloquent\Collection {#1483} "next" => array:2 [ "refs" => "1341262" "type" => "book_page" ] "previous" => array:2 [ "refs" => "1341260" "type" => "book_page" ] "tasks" => Illuminate\Database\Eloquent\Collection {#1913} ] #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" => 1320051 "created_at" => "2026-04-10 13:58:26" "updated_at" => null "field_page_start" => "11" "field_page_end" => null "field_url" => "/10-klass/fizika/parfenteva-sbornik-zadach/1-48" "field_display_title" => "48" "field_outside_task" => null "field_task_type" => Illuminate\Database\Eloquent\Collection {#1037} "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 {#1035} "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1075} "parent_branches" => Illuminate\Database\Eloquent\Collection {#1412} "content" => Illuminate\Database\Eloquent\Collection {#1413} "next" => array:2 [ "refs" => "1320052" "type" => "task" ] "previous" => array:2 [ "refs" => "1320050" "type" => "task" ] "book" => Illuminate\Database\Eloquent\Collection {#1464} "page" => array:2 [ "refs" => "1341261" "type" => "book_page" ] ] #changes: [] #casts: [] #classCastCache: [] #attributeCastCache: [] #dateFormat: null #appends: [] #dispatchesEvents: [] #observables: [] #relations: [] #touches: [] +timestamps: true +usesUniqueIds: false #hidden: [] #visible: [] #fillable: [] #guarded: array:1 [ 0 => "*" ] }
№48 (с. 11)
Условие. №48 (с. 11)
скриншот условия
48. По шоссе со скоростью 10 м/с едет автобус. Человек находится на расстоянии 100 м от шоссе и 300 м от автобуса. В каком направлении должен идти человек, чтобы выйти на шоссе раньше автобуса или одновременно с ним? Скорость человека 5 м/с.
Решение. №48 (с. 11)
Дано:
Скорость автобуса $v_а = 10$ м/с
Скорость человека $v_ч = 5$ м/с
Расстояние от человека до шоссе $h = 100$ м
Расстояние от человека до автобуса $D = 300$ м
Все данные представлены в системе СИ.
Найти:
Направление, в котором должен идти человек.
Решение:
Введем систему координат. Пусть шоссе совпадает с осью Ox, а перпендикуляр, опущенный из точки нахождения человека на шоссе, совпадает с осью Oy. Тогда человек находится в точке P с координатами $(0, h)$, то есть P(0, 100 м).
Автобус B находится на шоссе (ось Ox). Расстояние от человека до автобуса $D=PB=300$ м. Точка O(0,0) — это проекция положения человека на шоссе. Рассмотрим прямоугольный треугольник POB. По теореме Пифагора найдем расстояние OB — начальное расстояние по шоссе от автобуса до ближайшей к человеку точки на шоссе:
$OB = \sqrt{PB^2 - PO^2} = \sqrt{D^2 - h^2} = \sqrt{300^2 - 100^2} = \sqrt{90000 - 10000} = \sqrt{80000} = 200\sqrt{2}$ м.
Скорость автобуса ($10$ м/с) больше скорости человека ($\text{5}$ м/с). Человек сможет выйти на шоссе раньше автобуса или одновременно с ним только в том случае, если автобус движется ему навстречу (в сторону точки O). Таким образом, начальная координата автобуса B будет $(-200\sqrt{2}, 0)$, и он движется в положительном направлении оси Ox.
Пусть человек и автобус встречаются в точке M на шоссе с координатой $(x, 0)$. Человек должен выбрать такое $\text{x}$, чтобы его время в пути $t_ч$ было меньше или равно времени в пути автобуса $t_а$.
Время движения человека до точки M:
$t_ч = \frac{\text{расстояние PM}}{v_ч} = \frac{\sqrt{(x-0)^2 + (100-0)^2}}{5} = \frac{\sqrt{x^2 + 10000}}{5}$
Время движения автобуса до точки M:
$t_а = \frac{\text{расстояние BM}}{v_а} = \frac{x - (-200\sqrt{2})}{10} = \frac{x + 200\sqrt{2}}{10}$
Условие задачи: $t_ч \le t_а$.
$\frac{\sqrt{x^2 + 10000}}{5} \le \frac{x + 200\sqrt{2}}{10}$
Умножим обе части на 10:
$2\sqrt{x^2 + 10000} \le x + 200\sqrt{2}$
Левая часть неравенства всегда неотрицательна, значит и правая должна быть такой же. Возведем обе части в квадрат:
$4(x^2 + 10000) \le (x + 200\sqrt{2})^2$
$4x^2 + 40000 \le x^2 + 400\sqrt{2}x + 80000$
$3x^2 - 400\sqrt{2}x - 40000 \le 0$
Для решения этого квадратного неравенства найдем корни соответствующего уравнения $3x^2 - 400\sqrt{2}x - 40000 = 0$:
Дискриминант $D_k = (b/2)^2 - ac = (-200\sqrt{2})^2 - 3(-40000) = 80000 + 120000 = 200000$.
Корни уравнения:
$x_{1,2} = \frac{-b/2 \pm \sqrt{D_k}}{a} = \frac{200\sqrt{2} \pm \sqrt{200000}}{3} = \frac{200\sqrt{2} \pm 200\sqrt{5}}{3} = \frac{200}{3}(\sqrt{2} \pm \sqrt{5})$
Парабола $y=3x^2 - 400\sqrt{2}x - 40000$ имеет ветви, направленные вверх, поэтому неравенство выполняется между корнями:
$\frac{200}{3}(\sqrt{2} - \sqrt{5}) \le x \le \frac{200}{3}(\sqrt{2} + \sqrt{5})$
Это диапазон координат на шоссе, в которые должен целиться человек. Направление его движения можно охарактеризовать углом $\alpha$ между его траекторией (отрезок PM) и перпендикуляром к шоссе (отрезок PO).
Из прямоугольного треугольника POM имеем: $\tan(\alpha) = \frac{OM}{PO} = \frac{x}{100}$.
Найдем диапазон для $\tan(\alpha)$:
$\frac{1}{100} \cdot \frac{200}{3}(\sqrt{2} - \sqrt{5}) \le \tan(\alpha) \le \frac{1}{100} \cdot \frac{200}{3}(\sqrt{2} + \sqrt{5})$
$\frac{2}{3}(\sqrt{2} - \sqrt{5}) \le \tan(\alpha) \le \frac{2}{3}(\sqrt{2} + \sqrt{5})$
Приближенные значения: $\sqrt{2} \approx 1.414$, $\sqrt{5} \approx 2.236$.
$\tan(\alpha_{min}) \approx \frac{2}{3}(1.414 - 2.236) \approx -0.548 \implies \alpha_{min} \approx -28.7^\circ$
$\tan(\alpha_{max}) \approx \frac{2}{3}(1.414 + 2.236) \approx 2.433 \implies \alpha_{max} \approx 67.7^\circ$
Угол $\alpha$ отсчитывается от перпендикуляра к шоссе. Положительные значения угла соответствуют направлению в сторону движения автобуса, а отрицательные — в противоположную.
Ответ:
Человек должен идти в направлении, составляющем с перпендикуляром к шоссе угол $\alpha$ в диапазоне от $\arctan\left(\frac{2}{3}(\sqrt{2} - \sqrt{5})\right)$ до $\arctan\left(\frac{2}{3}(\sqrt{2} + \sqrt{5})\right)$. Приблизительно это составляет сектор от $-28.7^\circ$ до $67.7^\circ$, где положительный угол отсчитывается от перпендикуляра к шоссе в сторону движения автобуса.
Другие задания:
Помогло решение? Оставьте отзыв в комментариях ниже.
Присоединяйтесь к Телеграм-группе @top_gdz
ПрисоединитьсяМы подготовили для вас ответ c подробным объяснением домашего задания по физике за 10-11 класс, для упражнения номер 48 расположенного на странице 11 для 1-й части к сборнику задач серии классический курс 2007 года издания для учащихся школ и гимназий.
Теперь на нашем сайте ГДЗ.ТОП вы всегда легко и бесплатно найдёте условие с правильным ответом на вопрос «Как решить ДЗ» и «Как сделать» задание по физике к упражнению №48 (с. 11), автора: Парфентьева (Наталия Андреевна), 1-й части ФГОС (старый) учебного пособия издательства Просвещение.