Номер 111, страница 124 - гдз по физике 7-9 класс сборник задач Московкина, Волков

Физика, 7-9 класс Сборник задач, авторы: Московкина Елена Геннадьевна, Волков Владимир Анатольевич, издательство ВАКО, Москва, 2011

Авторы: Московкина Е. Г., Волков В. А.

Тип: Сборник задач

Издательство: ВАКО

Год издания: 2011 - 2026

Цвет обложки: синий

ISBN: 978-5-408-00459-1

9 класс. Вес тела. Сила упругости. Сила трения - номер 111, страница 124.

App\Models\Task {#1030 // resources/views/models/task/default.blade.php
  #connection: "mysql"
  #table: "tasks"
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  #attributes: array:24 [
    "id" => 1425785
    "created_at" => "2026-04-10 13:58:26"
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    "field_display_title" => "111"
    "field_outside_task" => null
    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1037
      #items: array:1 [
        0 => App\Models\Term {#1036
          #connection: "mysql"
          #table: "terms"
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          #attributes: array:6 [
            "id" => 26
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        0 => App\Models\Branch {#1045
          #connection: "mysql"
          #table: "branches"
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          #keyType: "int"
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              #items: array:1 [
                0 => App\Models\Book {#1056
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
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                    "field_class" => Illuminate\Database\Eloquent\Collection {#1064
                      #items: array:3 [
                        0 => App\Models\Term {#1060
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
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                          #attributes: array:6 [
                            "id" => 5456
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_cases" => array:6 [
                              "field_accusative_case" => "седьмой"
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                          #original: array:6 [
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                        1 => App\Models\Term {#1062
                          #connection: "mysql"
                          #table: "terms"
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                              "field_prepositional_case" => "восьмом"
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                        2 => App\Models\Term {#1059
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
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                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
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                            "field_plural_form" => null
                            "field_short_name" => null
                            "field_short_name_foreign" => null
                            "field_translit" => "sbornik zadach"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1068
                      #items: array:1 [
                        0 => App\Models\Term {#1076
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "rossiya"
                          ]
                          #original: array:6 [
                            "id" => 9
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Россия"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "rossiya"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1079
                      #items: array:1 [
                        0 => App\Models\Term {#1069
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "moskva"
                          ]
                          #original: array:6 [
                            "id" => 15
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "Москва"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "moskva"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1067
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1063
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1080
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1081
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1082
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1083
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2011"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => null
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1291"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_07/moskovkina-sz/"
                    "field_isbn" => "978-5-408-00459-1"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_07/moskovkina-sz/covers/cover1.webp?ts=1758729953"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_07/moskovkina-sz/covers/cover1.webp?ts=1758729953"
                        "alt" => ""
                        "width" => "1466"
                        "height" => "2407"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1084
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1085
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1086
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1090
                      #items: array:1 [
                        0 => App\Models\Term {#1087
                          #connection: "mysql"
                          #table: "terms"
                          #primaryKey: "id"
                          #keyType: "int"
                          +incrementing: false
                          #with: []
                          #withCount: []
                          +preventsLazyLoading: false
                          #perPage: 15
                          +exists: true
                          +wasRecentlyCreated: false
                          #escapeWhenCastingToString: false
                          #attributes: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "siniy"
                          ]
                          #original: array:6 [
                            "id" => 49
                            "created_at" => "2026-04-10 13:58:26"
                            "updated_at" => null
                            "name" => "синий"
                            "field_cases" => array:6 [
                              "field_accusative_case" => null
                              "field_creative_case" => null
                              "field_dative_case" => null
                              "field_genitive_case" => null
                              "field_nominative_case" => null
                              "field_prepositional_case" => null
                            ]
                            "field_translit" => "siniy"
                          ]
                          #changes: []
                          #casts: []
                          #classCastCache: []
                          #attributeCastCache: []
                          #dateFormat: null
                          #appends: []
                          #dispatchesEvents: []
                          #observables: []
                          #relations: []
                          #touches: []
                          +timestamps: true
                          +usesUniqueIds: false
                          #hidden: []
                          #visible: []
                          #fillable: []
                          #guarded: array:1 [
                            0 => "*"
                          ]
                        }
                      ]
                      #escapeWhenCastingToString: false
                    }
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 378
                      "subject" => 556
                      "class_subject" => 491
                    ]
                  ]
                  #original: array:50 [
                    "id" => 4994
                    "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 {#1061}
                    "field_class" => Illuminate\Database\Eloquent\Collection {#1064}
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1073}
                    "field_author" => Illuminate\Database\Eloquent\Collection {#1066}
                    "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1074}
                    "field_book_type" => Illuminate\Database\Eloquent\Collection {#1070}
                    "field_country" => Illuminate\Database\Eloquent\Collection {#1068}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1079}
                    "field_series" => Illuminate\Database\Eloquent\Collection {#1067}
                    "field_umk" => Illuminate\Database\Eloquent\Collection {#1063}
                    "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1080}
                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1081}
                    "field_publication_number" => null
                    "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1082}
                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1083}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2011"
                    "field_publication_year_until" => null
                    "field_part" => ""
                    "field_part_writing" => ""
                    "field_second_foreign_language" => null
                    "field_for_whom" => null
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "1291"
                    "field_priority" => null
                    "field_default_folder" => "/fizika_07/moskovkina-sz/"
                    "field_isbn" => "978-5-408-00459-1"
                    "field_cover" => array:1 [
                      0 => "/media/fizika_07/moskovkina-sz/covers/cover1.webp?ts=1758729953"
                    ]
                    "field_cover_alts" => array:1 [
                      0 => ""
                    ]
                    "field_covers" => array:1 [
                      0 => array:4 [
                        "path" => "/media/fizika_07/moskovkina-sz/covers/cover1.webp?ts=1758729953"
                        "alt" => ""
                        "width" => "1466"
                        "height" => "2407"
                      ]
                    ]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1084}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1085}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1086}
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1090}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [
                      "class" => 378
                      "subject" => 556
                      "class_subject" => 491
                    ]
                  ]
                  #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 {#1049
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1424795
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "9 класс"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1047}
            "field_page_start" => "111"
            "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 {#1057}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1049}
          ]
          #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 {#1112
      #items: array:2 [
        0 => App\Models\Branch {#1120
          #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" => 1424795
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "9 класс"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1121
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "111"
            "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 {#1122
              #items: array:1 [
                0 => App\Models\Book {#1056}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1123
              #items: []
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1424795
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "9 класс"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1121}
            "field_page_start" => "111"
            "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 {#1122}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1123}
          ]
          #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 {#1124
          #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" => 1424799
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Вес тела. Сила упругости. Сила трения"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1125
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_page_start" => "124"
            "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 {#1126
              #items: array:1 [
                0 => App\Models\Book {#1056}
              ]
              #escapeWhenCastingToString: false
            }
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1127
              #items: array:1 [
                0 => App\Models\Branch {#1045}
              ]
              #escapeWhenCastingToString: false
            }
          ]
          #original: array:24 [
            "id" => 1424799
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Вес тела. Сила упругости. Сила трения"
            "field_branch_order" => null
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1125}
            "field_page_start" => "124"
            "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 {#1126}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1127}
          ]
          #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 {#1038
      #items: array:2 [
        0 => App\Models\Element {#1103
          #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" => 1678318
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1092
              #items: array:1 [
                0 => App\Models\Edition {#1095
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 6044
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1093
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1054
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1052
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1088
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6044
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1093}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1054}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1052}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1088}
                    "field_content_source" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1425785"
              "type" => "task"
            ]
            "text" => "<p><strong>111.</strong> Тело массой 2 кг движется по горизонтальной поверхности с ускорением $2 \text{ м/с}^2$ под действием горизонтальной силы. Найдите величину этой силы, если коэффициент трения между телом и поверхностью 0,2.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "111-1.jpg"
                "alt" => null
                "width" => "2571"
                "height" => 561
                "path" => "/media/fizika_07/moskovkina-sz/0-9/111-1.webp?ts=1758885861"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1678318
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1092}
            "task" => array:2 [
              "refs" => "1425785"
              "type" => "task"
            ]
            "text" => "<p><strong>111.</strong> Тело массой 2 кг движется по горизонтальной поверхности с ускорением $2 \text{ м/с}^2$ под действием горизонтальной силы. Найдите величину этой силы, если коэффициент трения между телом и поверхностью 0,2.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "111-1.jpg"
                "alt" => null
                "width" => "2571"
                "height" => 561
                "path" => "/media/fizika_07/moskovkina-sz/0-9/111-1.webp?ts=1758885861"
              ]
            ]
          ]
          #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 {#1101
          #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" => 1782166
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1051
              #items: array:1 [
                0 => App\Models\Edition {#1041
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:21 [
                    "id" => 6518
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1043
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1119
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1048
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1034
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6518
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1043}
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => "0"
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Gemini 2.5 Pro"
                    "field_moderator" => "tolik"
                    "field_edition_type" => "solution"
                    "field_root_dir" => "1-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1119}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1048}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1034}
                    "field_content_source" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
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                  #touches: []
                  +timestamps: true
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                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "task" => array:2 [
              "refs" => "1425785"
              "type" => "task"
            ]
            "text" => "<p><strong>Дано:</strong></p><p>$m = 2$ кг</p><p>$a = 2$ м/с²</p><p>$\mu = 0,2$</p><p>Примем ускорение свободного падения $g = 10$ м/с².</p><p><strong>Найти:</strong></p><p>$\text{F}$</p><p><strong>Решение:</strong></p><p>На тело, движущееся по горизонтальной поверхности, действуют четыре силы: приложенная горизонтальная сила $\text{F}$, сила трения скольжения $F_{тр}$, сила тяжести $mg$ и сила нормальной реакции опоры $\text{N}$.</p><p>Согласно второму закону Ньютона, векторная сумма всех сил, действующих на тело, равна произведению массы тела на сообщаемое этой силой ускорение:</p><p>$\vec{F} + \vec{F}_{тр} + m\vec{g} + \vec{N} = m\vec{a}$</p><p>Для решения задачи выберем систему координат. Направим ось OX горизонтально, по направлению движения тела, а ось OY — вертикально вверх, перпендикулярно поверхности.</p><p>Запишем второй закон Ньютона в проекциях на эти оси.</p><p>Проекция на ось OY:</p><p>$N - mg = 0$</p><p>Поскольку тело не движется в вертикальном направлении, его ускорение вдоль оси OY равно нулю. Из этого уравнения следует, что сила нормальной реакции опоры уравновешивает силу тяжести:</p><p>$N = mg$</p><p>Проекция на ось OX:</p><p>$F - F_{тр} = ma$</p><p>Приложенная сила $\text{F}$ сонаправлена с осью OX, а сила трения $F_{тр}$ направлена в противоположную сторону.</p><p>Сила трения скольжения связана с силой нормальной реакции опоры через коэффициент трения $\mu$:</p><p>$F_{тр} = \mu N$</p><p>Подставим в эту формулу ранее найденное выражение для $\text{N}$:</p><p>$F_{тр} = \mu mg$</p><p>Теперь подставим полученное выражение для силы трения в уравнение для оси OX:</p><p>$F - \mu mg = ma$</p><p>Выразим из этого уравнения искомую величину силы $\text{F}$:</p><p>$F = ma + \mu mg = m(a + \mu g)$</p><p>Подставим числовые значения из условия задачи и выполним вычисления:</p><p>$F = 2 \cdot (2 + 0,2 \cdot 10) = 2 \cdot (2 + 2) = 2 \cdot 4 = 8$ Н.</p><p><strong>Ответ:</strong> величина силы равна 8 Н.</p>"
          ]
          #original: array:6 [
            "id" => 1782166
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1051}
            "task" => array:2 [
              "refs" => "1425785"
              "type" => "task"
            ]
            "text" => "<p><strong>Дано:</strong></p><p>$m = 2$ кг</p><p>$a = 2$ м/с²</p><p>$\mu = 0,2$</p><p>Примем ускорение свободного падения $g = 10$ м/с².</p><p><strong>Найти:</strong></p><p>$\text{F}$</p><p><strong>Решение:</strong></p><p>На тело, движущееся по горизонтальной поверхности, действуют четыре силы: приложенная горизонтальная сила $\text{F}$, сила трения скольжения $F_{тр}$, сила тяжести $mg$ и сила нормальной реакции опоры $\text{N}$.</p><p>Согласно второму закону Ньютона, векторная сумма всех сил, действующих на тело, равна произведению массы тела на сообщаемое этой силой ускорение:</p><p>$\vec{F} + \vec{F}_{тр} + m\vec{g} + \vec{N} = m\vec{a}$</p><p>Для решения задачи выберем систему координат. Направим ось OX горизонтально, по направлению движения тела, а ось OY — вертикально вверх, перпендикулярно поверхности.</p><p>Запишем второй закон Ньютона в проекциях на эти оси.</p><p>Проекция на ось OY:</p><p>$N - mg = 0$</p><p>Поскольку тело не движется в вертикальном направлении, его ускорение вдоль оси OY равно нулю. Из этого уравнения следует, что сила нормальной реакции опоры уравновешивает силу тяжести:</p><p>$N = mg$</p><p>Проекция на ось OX:</p><p>$F - F_{тр} = ma$</p><p>Приложенная сила $\text{F}$ сонаправлена с осью OX, а сила трения $F_{тр}$ направлена в противоположную сторону.</p><p>Сила трения скольжения связана с силой нормальной реакции опоры через коэффициент трения $\mu$:</p><p>$F_{тр} = \mu N$</p><p>Подставим в эту формулу ранее найденное выражение для $\text{N}$:</p><p>$F_{тр} = \mu mg$</p><p>Теперь подставим полученное выражение для силы трения в уравнение для оси OX:</p><p>$F - \mu mg = ma$</p><p>Выразим из этого уравнения искомую величину силы $\text{F}$:</p><p>$F = ma + \mu mg = m(a + \mu g)$</p><p>Подставим числовые значения из условия задачи и выполним вычисления:</p><p>$F = 2 \cdot (2 + 0,2 \cdot 10) = 2 \cdot (2 + 2) = 2 \cdot 4 = 8$ Н.</p><p><strong>Ответ:</strong> величина силы равна 8 Н.</p>"
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    "book" => Illuminate\Database\Eloquent\Collection {#1106
      #items: array:1 [
        0 => App\Models\Book {#1056}
      ]
      #escapeWhenCastingToString: false
    }
    "page" => Illuminate\Database\Eloquent\Collection {#1042
      #items: array:1 [
        0 => App\Models\BookPage {#1108
          #connection: "mysql"
          #table: "book_pages"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
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          #perPage: 15
          +exists: true
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          #escapeWhenCastingToString: false
          #attributes: array:21 [
            "id" => 1426227
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_page_start" => "124"
            "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/page-124"
            "field_display_title" => "124"
            "field_folder" => "1"
            "field_image_name" => "124"
            "field_branch_parent" => Illuminate\Database\Eloquent\Collection {#1102
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_weight" => "0"
            "field_book_parent" => Illuminate\Database\Eloquent\Collection {#1096
              #items: array:1 [
                0 => App\Models\Book {#1056}
              ]
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            "edition_groups" => Illuminate\Database\Eloquent\Collection {#1100
              #items: []
              #escapeWhenCastingToString: false
            }
            "content" => Illuminate\Database\Eloquent\Collection {#1116
              #items: array:1 [
                0 => App\Models\Element {#1113
                  #connection: "mysql"
                  #table: "elements"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: true
                  #with: []
                  #withCount: []
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                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:6 [
                    "id" => 1678759
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "edition" => Illuminate\Database\Eloquent\Collection {#1128
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "book_page" => array:2 [
                      "refs" => "1426227"
                      "type" => "book_page"
                    ]
                    "img" => array:1 [
                      0 => array:5 [ …5]
                    ]
                  ]
                  #original: array:6 [
                    "id" => 1678759
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "edition" => Illuminate\Database\Eloquent\Collection {#1128}
                    "book_page" => array:2 [
                      "refs" => "1426227"
                      "type" => "book_page"
                    ]
                    "img" => array:1 [
                      0 => array:5 [ …5]
                    ]
                  ]
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                  +timestamps: true
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "next" => array:2 [
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            "tasks" => Illuminate\Database\Eloquent\Collection {#1188
              #items: array:9 [
                0 => App\Models\Task {#1204
                  #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" => 1425782
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-108"
                    "field_display_title" => "108"
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                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1205
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
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                    "field_metatags_title" => null
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                    "field_h1" => null
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                    "field_match" => null
                    "breadcrumbs" => []
                    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1206
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1207
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1244
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "content" => Illuminate\Database\Eloquent\Collection {#1208
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "next" => array:2 [
                      "refs" => "1425783"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425781"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1238
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "page" => array:2 [
                      "refs" => "1426227"
                      "type" => "book_page"
                    ]
                  ]
                  #original: array:24 [
                    "id" => 1425782
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-108"
                    "field_display_title" => "108"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1205}
                    "field_metatags_title" => null
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                    "field_h1" => null
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                    "breadcrumbs" => []
                    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1206}
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1207}
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1244}
                    "content" => Illuminate\Database\Eloquent\Collection {#1208}
                    "next" => array:2 [
                      "refs" => "1425783"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425781"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1238}
                    "page" => array:2 [
                      "refs" => "1426227"
                      "type" => "book_page"
                    ]
                  ]
                  #changes: []
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                  +timestamps: true
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                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
                1 => App\Models\Task {#1241
                  #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" => 1425783
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-109"
                    "field_display_title" => "109"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1249
                      #items: array:1 [ …1]
                      #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 {#1236
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1239
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1209
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "content" => Illuminate\Database\Eloquent\Collection {#1211
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "next" => array:2 [
                      "refs" => "1425784"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425782"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1227
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "page" => array:2 [
                      "refs" => "1426227"
                      "type" => "book_page"
                    ]
                  ]
                  #original: array:24 [
                    "id" => 1425783
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-109"
                    "field_display_title" => "109"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1249}
                    "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 {#1236}
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1239}
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1209}
                    "content" => Illuminate\Database\Eloquent\Collection {#1211}
                    "next" => array:2 [
                      "refs" => "1425784"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425782"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1227}
                    "page" => array:2 [
                      "refs" => "1426227"
                      "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 => "*"
                  ]
                }
                2 => App\Models\Task {#1231
                  #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" => 1425784
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-110"
                    "field_display_title" => "110"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1240
                      #items: array:1 [ …1]
                      #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 {#1225
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1229
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1230
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "content" => Illuminate\Database\Eloquent\Collection {#1228
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "next" => array:2 [
                      "refs" => "1425785"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425783"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1215
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "page" => array:2 [
                      "refs" => "1426227"
                      "type" => "book_page"
                    ]
                  ]
                  #original: array:24 [
                    "id" => 1425784
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-110"
                    "field_display_title" => "110"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1240}
                    "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 {#1225}
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1229}
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1230}
                    "content" => Illuminate\Database\Eloquent\Collection {#1228}
                    "next" => array:2 [
                      "refs" => "1425785"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425783"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1215}
                    "page" => array:2 [
                      "refs" => "1426227"
                      "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 => "*"
                  ]
                }
                3 => App\Models\Task {#1218
                  #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" => 1425785
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-111"
                    "field_display_title" => "111"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1226
                      #items: array:1 [ …1]
                      #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 {#1213
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1217
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1219
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "content" => Illuminate\Database\Eloquent\Collection {#1216
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "next" => array:2 [
                      "refs" => "1425786"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425784"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1214
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "page" => array:2 [
                      "refs" => "1426227"
                      "type" => "book_page"
                    ]
                  ]
                  #original: array:24 [
                    "id" => 1425785
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-111"
                    "field_display_title" => "111"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1226}
                    "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 {#1213}
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1217}
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1219}
                    "content" => Illuminate\Database\Eloquent\Collection {#1216}
                    "next" => array:2 [
                      "refs" => "1425786"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425784"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1214}
                    "page" => array:2 [
                      "refs" => "1426227"
                      "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 => "*"
                  ]
                }
                4 => App\Models\Task {#1247
                  #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" => 1425786
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-112"
                    "field_display_title" => "112"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1245
                      #items: array:1 [ …1]
                      #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 {#1248
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1246
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1260
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "content" => Illuminate\Database\Eloquent\Collection {#1262
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "next" => array:2 [
                      "refs" => "1425787"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425785"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1268
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "page" => array:2 [
                      "refs" => "1426227"
                      "type" => "book_page"
                    ]
                  ]
                  #original: array:24 [
                    "id" => 1425786
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-112"
                    "field_display_title" => "112"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1245}
                    "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 {#1248}
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1246}
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1260}
                    "content" => Illuminate\Database\Eloquent\Collection {#1262}
                    "next" => array:2 [
                      "refs" => "1425787"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425785"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1268}
                    "page" => array:2 [
                      "refs" => "1426227"
                      "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 => "*"
                  ]
                }
                5 => App\Models\Task {#1263
                  #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" => 1425787
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-113"
                    "field_display_title" => "113"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1261
                      #items: array:1 [ …1]
                      #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 {#1270
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1266
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1264
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "content" => Illuminate\Database\Eloquent\Collection {#1265
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "next" => array:2 [
                      "refs" => "1425788"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425786"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1280
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "page" => array:2 [
                      "refs" => "1426227"
                      "type" => "book_page"
                    ]
                  ]
                  #original: array:24 [
                    "id" => 1425787
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-113"
                    "field_display_title" => "113"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1261}
                    "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 {#1270}
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1266}
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1264}
                    "content" => Illuminate\Database\Eloquent\Collection {#1265}
                    "next" => array:2 [
                      "refs" => "1425788"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425786"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1280}
                    "page" => array:2 [
                      "refs" => "1426227"
                      "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 => "*"
                  ]
                }
                6 => App\Models\Task {#1275
                  #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" => 1425788
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-114"
                    "field_display_title" => "114"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1267
                      #items: array:1 [ …1]
                      #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 {#1282
                      #items: []
                      #escapeWhenCastingToString: false
                    }
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1278
                      #items: array:1 [ …1]
                      #escapeWhenCastingToString: false
                    }
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1276
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "content" => Illuminate\Database\Eloquent\Collection {#1277
                      #items: array:2 [ …2]
                      #escapeWhenCastingToString: false
                    }
                    "next" => array:2 [
                      "refs" => "1425789"
                      "type" => "task"
                    ]
                    "previous" => array:2 [
                      "refs" => "1425787"
                      "type" => "task"
                    ]
                    "book" => Illuminate\Database\Eloquent\Collection {#1292 …2}
                    "page" => array:2 [ …2]
                  ]
                  #original: array:24 [
                    "id" => 1425788
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "field_page_start" => "124"
                    "field_page_end" => null
                    "field_url" => "/7-klass/fizika/moskovkina-sbornik-zadach/9-114"
                    "field_display_title" => "114"
                    "field_outside_task" => null
                    "field_task_type" => Illuminate\Database\Eloquent\Collection {#1267}
                    "field_metatags_title" => null
                    "field_metatags_description" => null
                    "field_h1" => null
                    "field_description_top" => null
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                    "breadcrumbs" => []
                    "edition_groups" => Illuminate\Database\Eloquent\Collection {#1282}
                    "top_parent_branch" => Illuminate\Database\Eloquent\Collection {#1278}
                    "parent_branches" => Illuminate\Database\Eloquent\Collection {#1276}
                    "content" => Illuminate\Database\Eloquent\Collection {#1277}
                    "next" => array:2 [ …2]
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№111 (с. 124)
Условие. №111 (с. 124)
скриншот условия
Физика, 7-9 класс Сборник задач, авторы: Московкина Елена Геннадьевна, Волков Владимир Анатольевич, издательство ВАКО, Москва, 2011, страница 124, номер 111, Условие

111. Тело массой 2 кг движется по горизонтальной поверхности с ускорением $2 \text{ м/с}^2$ под действием горизонтальной силы. Найдите величину этой силы, если коэффициент трения между телом и поверхностью 0,2.

Решение. №111 (с. 124)

Дано:

$m = 2$ кг

$a = 2$ м/с²

$\mu = 0,2$

Примем ускорение свободного падения $g = 10$ м/с².

Найти:

$\text{F}$

Решение:

На тело, движущееся по горизонтальной поверхности, действуют четыре силы: приложенная горизонтальная сила $\text{F}$, сила трения скольжения $F_{тр}$, сила тяжести $mg$ и сила нормальной реакции опоры $\text{N}$.

Согласно второму закону Ньютона, векторная сумма всех сил, действующих на тело, равна произведению массы тела на сообщаемое этой силой ускорение:

$\vec{F} + \vec{F}_{тр} + m\vec{g} + \vec{N} = m\vec{a}$

Для решения задачи выберем систему координат. Направим ось OX горизонтально, по направлению движения тела, а ось OY — вертикально вверх, перпендикулярно поверхности.

Запишем второй закон Ньютона в проекциях на эти оси.

Проекция на ось OY:

$N - mg = 0$

Поскольку тело не движется в вертикальном направлении, его ускорение вдоль оси OY равно нулю. Из этого уравнения следует, что сила нормальной реакции опоры уравновешивает силу тяжести:

$N = mg$

Проекция на ось OX:

$F - F_{тр} = ma$

Приложенная сила $\text{F}$ сонаправлена с осью OX, а сила трения $F_{тр}$ направлена в противоположную сторону.

Сила трения скольжения связана с силой нормальной реакции опоры через коэффициент трения $\mu$:

$F_{тр} = \mu N$

Подставим в эту формулу ранее найденное выражение для $\text{N}$:

$F_{тр} = \mu mg$

Теперь подставим полученное выражение для силы трения в уравнение для оси OX:

$F - \mu mg = ma$

Выразим из этого уравнения искомую величину силы $\text{F}$:

$F = ma + \mu mg = m(a + \mu g)$

Подставим числовые значения из условия задачи и выполним вычисления:

$F = 2 \cdot (2 + 0,2 \cdot 10) = 2 \cdot (2 + 2) = 2 \cdot 4 = 8$ Н.

Ответ: величина силы равна 8 Н.

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