Номер 24, страница 104, 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

Часть 1. Механические явления. Глава II. Динамика. Параграф 11. Силы трения - номер 24, страница 104.

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                    "field_link_to_source" => null
                    "field_tasks_count" => "1111"
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                    "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 {#1104 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1105 …2}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1106 …2}
                    "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik"
                    "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]
                  ]
                  #changes: []
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                  #attributeCastCache: []
                  #dateFormat: null
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                  #dispatchesEvents: []
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                  #touches: []
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                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1109
              #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 {#1076}
            "field_page_start" => "6"
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            "field_h1" => null
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1077}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1109}
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          #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" => 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 {#1111
              #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
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            "field_metatags_description" => null
            "field_h1" => null
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            "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 [
                    "id" => 2980
                    "created_at" => "2026-04-10 13:58:26"
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                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1114 …2}
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1118 …2}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1120 …2}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1125 …2}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1126 …2}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1128 …2}
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                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1134 …2}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1135 …2}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1136 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1137 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
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                    "field_part" => "1, 2"
                    "field_part_writing" => "Часть"
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                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
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                    "field_tasks_count" => "1111"
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                    "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]
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                    "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1142 …2}
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                    "breadcrumbs" => array:3 [ …3]
                  ]
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                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1114 …2}
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                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1125 …2}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1126 …2}
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                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1135 …2}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1136 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1137 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
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                    "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]
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                    "breadcrumbs" => array:3 [ …3]
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                    0 => "*"
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                }
              ]
              #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: []
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                  #perPage: 15
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                  #escapeWhenCastingToString: false
                  #attributes: array:24 [
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                    "created_at" => "2026-04-10 13:58:26"
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                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1146 …2}
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                    "book" => Illuminate\Database\Eloquent\Collection {#1148 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1149 …2}
                  ]
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                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1146 …2}
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                    "book" => Illuminate\Database\Eloquent\Collection {#1148 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1149 …2}
                  ]
                  #changes: []
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                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
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                  #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 {#1111}
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            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1112}
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          #hidden: []
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          #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" => 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 {#1151
              #items: array:1 [
                0 => App\Models\Term {#1152
                  #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: []
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                  #attributeCastCache: []
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "59"
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            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1153
              #items: array:1 [
                0 => App\Models\Book {#1154
                  #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"
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                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1155 …2}
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                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1159 …2}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1161 …2}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1166 …2}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1167 …2}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1169 …2}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1171 …2}
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                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1175 …2}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1176 …2}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1177 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1178 …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 {#1180 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1181 …2}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1182 …2}
                    "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1183 …2}
                    "field_metatags_title" => null
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                    "breadcrumbs" => array:3 [ …3]
                  ]
                  #original: array:50 [
                    "id" => 2980
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                    "field_subject" => Illuminate\Database\Eloquent\Collection {#1155 …2}
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                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1166 …2}
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                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1174 …2}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1175 …2}
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                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1177 …2}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1178 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2016"
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                    "field_part" => "1, 2"
                    "field_part_writing" => "Часть"
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                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
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                    "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 {#1180 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1181 …2}
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                    "field_url" => "/9-klass/fizika/gendenshtejn-uchebnik"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1183 …2}
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                    0 => "*"
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            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1185
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                0 => App\Models\Branch {#1186
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                  #attributes: array:24 [
                    "id" => 1433207
                    "created_at" => "2026-04-10 13:58:26"
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                    "field_display_title" => "Механические явления"
                    "field_branch_order" => null
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1187 …2}
                    "field_page_start" => "6"
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                    "field_display_branch_page" => "1"
                    "field_branch_title_in_content" => "0"
                    "field_navigation_title" => null
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                    "field_h1" => null
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                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1188 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1220 …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 {#1187 …2}
                    "field_page_start" => "6"
                    "field_branch_display" => "0"
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                    "field_display_branch_in_title" => "1"
                    "field_display_task_interval" => "0"
                    "field_display_branch_page" => "1"
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                    "field_navigation_title" => null
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                    "field_branch_cover" => []
                    "field_branch_covers" => []
                    "book" => Illuminate\Database\Eloquent\Collection {#1188 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1220 …2}
                  ]
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                    0 => "*"
                  ]
                }
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          ]
          #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 {#1151}
            "field_page_start" => "59"
            "field_branch_display" => "0"
            "field_branch_expanded" => "0"
            "field_display_branch_in_title" => "1"
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            "field_display_branch_page" => "1"
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            "field_navigation_title" => null
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            "field_description_top" => null
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            "field_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1153}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1185}
          ]
          #changes: []
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          #attributeCastCache: []
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          #hidden: []
          #visible: []
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          #guarded: array:1 [
            0 => "*"
          ]
        }
        3 => App\Models\Branch {#1257
          #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 {#1258
              #items: array:1 [
                0 => App\Models\Term {#1259
                  #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: []
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                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
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                  #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 {#1260
              #items: array:1 [
                0 => App\Models\Book {#1261
                  #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 {#1262 …2}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1264 …2}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1266 …2}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1268 …2}
                     …41
                  ]
                  #original: array:50 [ …50]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
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                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [ …1]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1292
              #items: array:1 [
                0 => App\Models\Branch {#1293
                  #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" => 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 {#1258}
            "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 {#1260}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1292}
          ]
          #changes: []
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          #classCastCache: []
          #attributeCastCache: []
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            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1339
      #items: array:2 [
        0 => App\Models\Element {#1349
          #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" => 1696380
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1358
              #items: array:1 [
                0 => App\Models\Edition {#1350
                  #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" => "1433639"
              "type" => "task"
            ]
            "text" => "<p><strong>24.</strong> Когда с помощью горизонтальной пружины по столу равномерно перемещают брусок массой 600 г, удлинение пружины равно 5 мм. Коэффициент трения между бруском и столом равен 0,3. Чему равна жёсткость пружины?</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "24-1.jpg"
                "alt" => null
                "width" => "1578"
                "height" => 294
                "path" => "/media/fizika_09/gendenshtejn-u/0-11/24-1.webp?ts=1759348238"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1696380
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1358}
            "task" => array:2 [
              "refs" => "1433639"
              "type" => "task"
            ]
            "text" => "<p><strong>24.</strong> Когда с помощью горизонтальной пружины по столу равномерно перемещают брусок массой 600 г, удлинение пружины равно 5 мм. Коэффициент трения между бруском и столом равен 0,3. Чему равна жёсткость пружины?</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "24-1.jpg"
                "alt" => null
                "width" => "1578"
                "height" => 294
                "path" => "/media/fizika_09/gendenshtejn-u/0-11/24-1.webp?ts=1759348238"
              ]
            ]
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
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          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Element {#1356
          #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" => 1780450
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1366
              #items: array:1 [
                0 => App\Models\Edition {#1357
                  #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: []
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                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [ …1]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1433639"
              "type" => "task"
            ]
            "text" => "<p><strong>Дано:</strong></p><p>$m = 600 \text{ г} = 0,6 \text{ кг}$</p><p>$x = 5 \text{ мм} = 0,005 \text{ м}$</p><p>$\mu = 0,3$</p><p>$g \approx 10 \text{ Н/кг}$ (ускорение свободного падения)</p><p><strong>Найти:</strong></p><p>$\text{k}$</p><p><strong>Решение:</strong></p><p>Поскольку брусок движется по столу равномерно, его ускорение равно нулю. Согласно первому закону Ньютона, это означает, что равнодействующая всех сил, приложенных к бруску, равна нулю. Это условие выполняется как для горизонтальных, так и для вертикальных сил.</p><p>В горизонтальном направлении на брусок действуют две силы: сила упругости со стороны пружины $F_{упр}$, направленная в сторону движения, и сила трения скольжения $F_{тр}$, направленная в противоположную сторону. Так как движение равномерное, эти силы уравновешивают друг друга:</p><p>$F_{упр} = F_{тр}$</p><p>Сила упругости определяется законом Гука:</p><p>$F_{упр} = k \cdot x$</p><p>где $\text{k}$ – искомая жёсткость пружины, а $\text{x}$ – её удлинение.</p><p>Сила трения скольжения вычисляется по формуле:</p><p>$F_{тр} = \mu \cdot N$</p><p>где $\mu$ – коэффициент трения, а $\text{N}$ – сила нормальной реакции опоры.</p><p>В вертикальном направлении на брусок действуют сила тяжести $F_т = m \cdot g$ и сила нормальной реакции опоры $\text{N}$. Так как в вертикальном направлении движения нет, эти силы также уравновешены:</p><p>$N = F_т = m \cdot g$</p><p>Теперь подставим выражение для силы нормальной реакции в формулу для силы трения:</p><p>$F_{тр} = \mu \cdot m \cdot g$</p><p>Приравняем выражения для силы упругости и силы трения:</p><p>$k \cdot x = \mu \cdot m \cdot g$</p><p>Из этого уравнения выразим жёсткость пружины $\text{k}$:</p><p>$k = \frac{\mu \cdot m \cdot g}{x}$</p><p>Подставим числовые значения в полученную формулу:</p><p>$k = \frac{0,3 \cdot 0,6 \text{ кг} \cdot 10 \text{ Н/кг}}{0,005 \text{ м}} = \frac{1,8 \text{ Н}}{0,005 \text{ м}} = 360 \text{ Н/м}$</p><p><strong>Ответ:</strong> жёсткость пружины равна $360 \text{ Н/м}$.</p>"
          ]
          #original: array:6 [
            "id" => 1780450
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1366}
            "task" => array:2 [
              "refs" => "1433639"
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            "text" => "<p><strong>Дано:</strong></p><p>$m = 600 \text{ г} = 0,6 \text{ кг}$</p><p>$x = 5 \text{ мм} = 0,005 \text{ м}$</p><p>$\mu = 0,3$</p><p>$g \approx 10 \text{ Н/кг}$ (ускорение свободного падения)</p><p><strong>Найти:</strong></p><p>$\text{k}$</p><p><strong>Решение:</strong></p><p>Поскольку брусок движется по столу равномерно, его ускорение равно нулю. Согласно первому закону Ньютона, это означает, что равнодействующая всех сил, приложенных к бруску, равна нулю. Это условие выполняется как для горизонтальных, так и для вертикальных сил.</p><p>В горизонтальном направлении на брусок действуют две силы: сила упругости со стороны пружины $F_{упр}$, направленная в сторону движения, и сила трения скольжения $F_{тр}$, направленная в противоположную сторону. Так как движение равномерное, эти силы уравновешивают друг друга:</p><p>$F_{упр} = F_{тр}$</p><p>Сила упругости определяется законом Гука:</p><p>$F_{упр} = k \cdot x$</p><p>где $\text{k}$ – искомая жёсткость пружины, а $\text{x}$ – её удлинение.</p><p>Сила трения скольжения вычисляется по формуле:</p><p>$F_{тр} = \mu \cdot N$</p><p>где $\mu$ – коэффициент трения, а $\text{N}$ – сила нормальной реакции опоры.</p><p>В вертикальном направлении на брусок действуют сила тяжести $F_т = m \cdot g$ и сила нормальной реакции опоры $\text{N}$. Так как в вертикальном направлении движения нет, эти силы также уравновешены:</p><p>$N = F_т = m \cdot g$</p><p>Теперь подставим выражение для силы нормальной реакции в формулу для силы трения:</p><p>$F_{тр} = \mu \cdot m \cdot g$</p><p>Приравняем выражения для силы упругости и силы трения:</p><p>$k \cdot x = \mu \cdot m \cdot g$</p><p>Из этого уравнения выразим жёсткость пружины $\text{k}$:</p><p>$k = \frac{\mu \cdot m \cdot g}{x}$</p><p>Подставим числовые значения в полученную формулу:</p><p>$k = \frac{0,3 \cdot 0,6 \text{ кг} \cdot 10 \text{ Н/кг}}{0,005 \text{ м}} = \frac{1,8 \text{ Н}}{0,005 \text{ м}} = 360 \text{ Н/м}$</p><p><strong>Ответ:</strong> жёсткость пружины равна $360 \text{ Н/м}$.</p>"
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№24 (с. 104)
Условие. №24 (с. 104)
скриншот условия
Физика, 9 класс Учебник, авторы: Генденштейн Лев Элевич, Булатова Альбина Александрова, Корнильев Игорь Николаевич, Кошкина Анжелика Васильевна, издательство Бином, Москва, 2016, бирюзового цвета, Часть 1, страница 104, номер 24, Условие

24. Когда с помощью горизонтальной пружины по столу равномерно перемещают брусок массой 600 г, удлинение пружины равно 5 мм. Коэффициент трения между бруском и столом равен 0,3. Чему равна жёсткость пружины?

Решение. №24 (с. 104)

Дано:

$m = 600 \text{ г} = 0,6 \text{ кг}$

$x = 5 \text{ мм} = 0,005 \text{ м}$

$\mu = 0,3$

$g \approx 10 \text{ Н/кг}$ (ускорение свободного падения)

Найти:

$\text{k}$

Решение:

Поскольку брусок движется по столу равномерно, его ускорение равно нулю. Согласно первому закону Ньютона, это означает, что равнодействующая всех сил, приложенных к бруску, равна нулю. Это условие выполняется как для горизонтальных, так и для вертикальных сил.

В горизонтальном направлении на брусок действуют две силы: сила упругости со стороны пружины $F_{упр}$, направленная в сторону движения, и сила трения скольжения $F_{тр}$, направленная в противоположную сторону. Так как движение равномерное, эти силы уравновешивают друг друга:

$F_{упр} = F_{тр}$

Сила упругости определяется законом Гука:

$F_{упр} = k \cdot x$

где $\text{k}$ – искомая жёсткость пружины, а $\text{x}$ – её удлинение.

Сила трения скольжения вычисляется по формуле:

$F_{тр} = \mu \cdot N$

где $\mu$ – коэффициент трения, а $\text{N}$ – сила нормальной реакции опоры.

В вертикальном направлении на брусок действуют сила тяжести $F_т = m \cdot g$ и сила нормальной реакции опоры $\text{N}$. Так как в вертикальном направлении движения нет, эти силы также уравновешены:

$N = F_т = m \cdot g$

Теперь подставим выражение для силы нормальной реакции в формулу для силы трения:

$F_{тр} = \mu \cdot m \cdot g$

Приравняем выражения для силы упругости и силы трения:

$k \cdot x = \mu \cdot m \cdot g$

Из этого уравнения выразим жёсткость пружины $\text{k}$:

$k = \frac{\mu \cdot m \cdot g}{x}$

Подставим числовые значения в полученную формулу:

$k = \frac{0,3 \cdot 0,6 \text{ кг} \cdot 10 \text{ Н/кг}}{0,005 \text{ м}} = \frac{1,8 \text{ Н}}{0,005 \text{ м}} = 360 \text{ Н/м}$

Ответ: жёсткость пружины равна $360 \text{ Н/м}$.

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