Номер 3, страница 63, часть 2 - гдз по физике 9 класс рабочая тетрадь Грачев, Погожев

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

Тип: рабочая тетрадь

Издательство: Просвещение

Год издания: 2021 - 2026

Часть: 2

Цвет обложки: синий

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

Часть 2. Глава 6. Механические колебания и волны. Параграф 35. Звук - номер 3, страница 63.

App\Models\Task {#1024 // resources/views/models/task/default.blade.php
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                    "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1097 …2}
                    "field_under_the_edition_degree" => null
                    "field_cover_description" => null
                    "field_publication_year" => "2021"
                    "field_publication_year_until" => null
                    "field_part" => "1, 2, 3"
                    "field_part_writing" => "Часть"
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                    "field_for_whom" => "Учебное издание"
                    "field_allowed" => null
                    "field_reserve_field" => null
                    "field_link_to_source" => null
                    "field_tasks_count" => "594"
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                    "field_default_folder" => "/fizika_09/grachev-rt/"
                    "field_isbn" => "978-5-09-098826-1 (ч.1) 978-5-09-098880-3 (ч.2) 978-5-09-098881-0 (ч.3)"
                    "field_cover" => array:3 [ …3]
                    "field_cover_alts" => array:3 [ …3]
                    "field_covers" => array:3 [ …3]
                    "field_popular_book" => "0"
                    "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1098 …2}
                    "field_new_book" => Illuminate\Database\Eloquent\Collection {#1099 …2}
                    "field_old_book" => Illuminate\Database\Eloquent\Collection {#1100 …2}
                    "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad"
                    "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1101 …2}
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                    "field_metatags_description" => null
                    "field_h1" => null
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                    "field_description_bottom" => null
                    "breadcrumbs" => array:3 [ …3]
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                    0 => "*"
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              ]
              #escapeWhenCastingToString: false
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            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1103
              #items: array:1 [
                0 => App\Models\Branch {#1104
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
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                  #with: []
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                    "created_at" => "2026-04-10 13:58:26"
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                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1105 …2}
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                    "book" => Illuminate\Database\Eloquent\Collection {#1107 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1108 …2}
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                  #original: array:24 [
                    "id" => 1434829
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                    "updated_at" => null
                    "field_display_title" => null
                    "field_branch_order" => "2"
                    "field_url" => null
                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1105 …2}
                    "field_page_start" => "3"
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                    "book" => Illuminate\Database\Eloquent\Collection {#1107 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1108 …2}
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                  #attributeCastCache: []
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                  #touches: []
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                  #hidden: []
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
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            "id" => 1434841
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
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            "field_branch_order" => "6"
            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1068}
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            "book" => Illuminate\Database\Eloquent\Collection {#1070}
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            0 => "*"
          ]
        }
        2 => App\Models\Branch {#1109
          #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" => 1434846
            "created_at" => "2026-04-10 13:58:26"
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            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1110
              #items: array:1 [
                0 => App\Models\Term {#1111
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
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                  #attributes: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #original: array:7 [
                    "id" => 32
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Параграф"
                    "field_cases" => array:6 [ …6]
                    "field_page_check_not_needed" => null
                    "field_short_name" => "§"
                  ]
                  #changes: []
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                  #attributeCastCache: []
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                    0 => "*"
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              ]
              #escapeWhenCastingToString: false
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            "field_page_start" => "62"
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            "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
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                  #attributes: array:50 [
                    "id" => 1203
                    "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_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}
                    "field_city" => Illuminate\Database\Eloquent\Collection {#1130 …2}
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                    "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1135 …2}
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                    "field_cover" => array:3 [ …3]
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                    "field_tasks_count" => "594"
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                    "field_cover" => array:3 [ …3]
                    "field_cover_alts" => array:3 [ …3]
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                    0 => "*"
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              #escapeWhenCastingToString: false
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            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1145
              #items: array:1 [
                0 => App\Models\Branch {#1146
                  #connection: "mysql"
                  #table: "branches"
                  #primaryKey: "id"
                  #keyType: "int"
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                    "book" => Illuminate\Database\Eloquent\Collection {#1149 …2}
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                    "field_branch_order" => "6"
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                    "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1147 …2}
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                    "book" => Illuminate\Database\Eloquent\Collection {#1149 …2}
                    "branch_parent" => Illuminate\Database\Eloquent\Collection {#1182 …2}
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                  +timestamps: true
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                  #visible: []
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                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
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          ]
          #original: array:24 [
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            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_display_title" => "Звук"
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            "field_url" => null
            "field_branch_type" => Illuminate\Database\Eloquent\Collection {#1110}
            "field_page_start" => "62"
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            "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_branch_cover" => []
            "field_branch_covers" => []
            "book" => Illuminate\Database\Eloquent\Collection {#1112}
            "branch_parent" => Illuminate\Database\Eloquent\Collection {#1145}
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          +timestamps: true
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            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "content" => Illuminate\Database\Eloquent\Collection {#1188
      #items: array:2 [
        0 => App\Models\Element {#1189
          #connection: "mysql"
          #table: "elements"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
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          #escapeWhenCastingToString: false
          #attributes: array:7 [
            "id" => 1698556
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1190
              #items: array:1 [
                0 => App\Models\Edition {#1191
                  #connection: "mysql"
                  #table: "editions"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
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                  #perPage: 15
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                  #attributes: array:21 [
                    "id" => 6173
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1192 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1194 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1195 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1196 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6173
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Условие"
                    "field_order" => "1"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1192 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text, image"
                    "field_page_content_mode" => "image"
                    "field_content_text_checked" => null
                    "field_page_content_text_checked" => "0"
                    "field_solution_author" => "Автор"
                    "field_moderator" => "stas"
                    "field_edition_type" => "statement"
                    "field_root_dir" => "0-"
                    "field_responsible" => Illuminate\Database\Eloquent\Collection {#1194 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1195 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1196 …2}
                    "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" => "1435168"
              "type" => "task"
            ]
            "text" => "<p><strong>3.</strong> Частота звучания чистого музыкального звука ноты «ля» равна 440 Гц. Какой частоты должен быть чистый музыкальный звук, у которого длина волны в воздухе будет равна длине звуковой волны ноты «ля» в воде?</p><p><em>Решение.</em></p><p><em>Ответ:</em> ___________.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "3-1.jpg"
                "alt" => null
                "width" => "1926"
                "height" => 574
                "path" => "/media/fizika_09/grachev-rt/0-35/3-1.webp?ts=1759402796"
              ]
            ]
          ]
          #original: array:7 [
            "id" => 1698556
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1190}
            "task" => array:2 [
              "refs" => "1435168"
              "type" => "task"
            ]
            "text" => "<p><strong>3.</strong> Частота звучания чистого музыкального звука ноты «ля» равна 440 Гц. Какой частоты должен быть чистый музыкальный звук, у которого длина волны в воздухе будет равна длине звуковой волны ноты «ля» в воде?</p><p><em>Решение.</em></p><p><em>Ответ:</em> ___________.</p>"
            "img" => array:1 [
              0 => array:5 [
                "name" => "3-1.jpg"
                "alt" => null
                "width" => "1926"
                "height" => 574
                "path" => "/media/fizika_09/grachev-rt/0-35/3-1.webp?ts=1759402796"
              ]
            ]
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
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          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
        1 => App\Models\Element {#1197
          #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" => 1734542
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1198
              #items: array:1 [
                0 => App\Models\Edition {#1199
                  #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" => 6327
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1200 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => null
                    "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 {#1202 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1203 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1204 …2}
                    "field_content_source" => null
                  ]
                  #original: array:21 [
                    "id" => 6327
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "title" => "Решение"
                    "field_order" => "2"
                    "field_publisher" => Illuminate\Database\Eloquent\Collection {#1200 …2}
                    "field_content_type" => "free"
                    "field_content_mode" => "text"
                    "field_page_content_mode" => ""
                    "field_content_text_checked" => null
                    "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 {#1202 …2}
                    "field_comment" => null
                    "field_similar_book" => Illuminate\Database\Eloquent\Collection {#1203 …2}
                    "field_process_formula" => "katex"
                    "field_edition_group" => Illuminate\Database\Eloquent\Collection {#1204 …2}
                    "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" => "1435168"
              "type" => "task"
            ]
            "text" => "<p><strong>Дано:</strong></p><p>Частота звука ноты «ля», $f_1 = 440$ Гц</p><p>Скорость звука в воде, $v_{вода} \approx 1500$ м/с (справочное значение)</p><p>Скорость звука в воздухе, $v_{воздух} \approx 340$ м/с (справочное значение)</p><p>Длина волны искомого звука в воздухе $\lambda_2$ равна длине волны ноты «ля» в воде $\lambda_1$.</p><p><strong>Найти:</strong></p><p>Частоту искомого звука, $f_2$.</p><p><strong>Решение:</strong></p><p>Длина волны $\lambda$ связана со скоростью ее распространения $v$ и частотой $f$ следующей формулой:</p><p>$\lambda = \frac{v}{f}$</p><p>1. Сначала найдем длину звуковой волны ноты «ля» ($f_1 = 440$ Гц) при ее распространении в воде. Скорость звука в воде $v_{вода}$.</p><p>$\lambda_1 = \frac{v_{вода}}{f_1}$</p><p>2. Длина волны второго, искомого, звука с частотой $f_2$ в воздухе (скорость звука $v_{воздух}$) равна:</p><p>$\lambda_2 = \frac{v_{воздух}}{f_2}$</p><p>3. По условию задачи, эти длины волн равны: $\lambda_1 = \lambda_2$.</p><p>Приравняем правые части выражений для длин волн:</p><p>$\frac{v_{вода}}{f_1} = \frac{v_{воздух}}{f_2}$</p><p>4. Из этого равенства выразим искомую частоту $f_2$:</p><p>$f_2 = f_1 \cdot \frac{v_{воздух}}{v_{вода}}$</p><p>5. Подставим числовые значения и выполним расчет:</p><p>$f_2 = 440 \text{ Гц} \cdot \frac{340 \text{ м/с}}{1500 \text{ м/с}} = 440 \cdot \frac{34}{150} = \frac{14960}{150} \approx 99,73$ Гц.</p><p>Округлим полученное значение до десятых.</p><p><strong>Ответ:</strong> $99,7$ Гц.</p>"
          ]
          #original: array:6 [
            "id" => 1734542
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "edition" => Illuminate\Database\Eloquent\Collection {#1198}
            "task" => array:2 [
              "refs" => "1435168"
              "type" => "task"
            ]
            "text" => "<p><strong>Дано:</strong></p><p>Частота звука ноты «ля», $f_1 = 440$ Гц</p><p>Скорость звука в воде, $v_{вода} \approx 1500$ м/с (справочное значение)</p><p>Скорость звука в воздухе, $v_{воздух} \approx 340$ м/с (справочное значение)</p><p>Длина волны искомого звука в воздухе $\lambda_2$ равна длине волны ноты «ля» в воде $\lambda_1$.</p><p><strong>Найти:</strong></p><p>Частоту искомого звука, $f_2$.</p><p><strong>Решение:</strong></p><p>Длина волны $\lambda$ связана со скоростью ее распространения $v$ и частотой $f$ следующей формулой:</p><p>$\lambda = \frac{v}{f}$</p><p>1. Сначала найдем длину звуковой волны ноты «ля» ($f_1 = 440$ Гц) при ее распространении в воде. Скорость звука в воде $v_{вода}$.</p><p>$\lambda_1 = \frac{v_{вода}}{f_1}$</p><p>2. Длина волны второго, искомого, звука с частотой $f_2$ в воздухе (скорость звука $v_{воздух}$) равна:</p><p>$\lambda_2 = \frac{v_{воздух}}{f_2}$</p><p>3. По условию задачи, эти длины волн равны: $\lambda_1 = \lambda_2$.</p><p>Приравняем правые части выражений для длин волн:</p><p>$\frac{v_{вода}}{f_1} = \frac{v_{воздух}}{f_2}$</p><p>4. Из этого равенства выразим искомую частоту $f_2$:</p><p>$f_2 = f_1 \cdot \frac{v_{воздух}}{v_{вода}}$</p><p>5. Подставим числовые значения и выполним расчет:</p><p>$f_2 = 440 \text{ Гц} \cdot \frac{340 \text{ м/с}}{1500 \text{ м/с}} = 440 \cdot \frac{34}{150} = \frac{14960}{150} \approx 99,73$ Гц.</p><p>Округлим полученное значение до десятых.</p><p><strong>Ответ:</strong> $99,7$ Гц.</p>"
          ]
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    "book" => Illuminate\Database\Eloquent\Collection {#1205
      #items: array:1 [
        0 => App\Models\Book {#1206
          #connection: "mysql"
          #table: "books"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: false
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
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          #escapeWhenCastingToString: false
          #attributes: array:50 [
            "id" => 1203
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_tree_default_status" => "tasks"
            "field_pages_status" => null
            "field_subject" => Illuminate\Database\Eloquent\Collection {#1207
              #items: array:1 [
                0 => App\Models\Term {#1208
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
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                  #perPage: 15
                  +exists: true
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                  #escapeWhenCastingToString: false
                  #attributes: array:10 [
                    "id" => 6493
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Физика"
                    "field_abbreviated_name" => null
                    "field_cases" => array:6 [ …6]
                    "field_foreign_lang_name" => null
                    "field_short_name" => null
                    "field_subject_type" => "technical_subject"
                    "field_translit" => "fizika"
                  ]
                  #original: array:10 [
                    "id" => 6493
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Физика"
                    "field_abbreviated_name" => null
                    "field_cases" => array:6 [ …6]
                    "field_foreign_lang_name" => null
                    "field_short_name" => null
                    "field_subject_type" => "technical_subject"
                    "field_translit" => "fizika"
                  ]
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                  +timestamps: true
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                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_class" => Illuminate\Database\Eloquent\Collection {#1209
              #items: array:1 [
                0 => App\Models\Term {#1210
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:6 [
                    "id" => 5458
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "9"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "devjatyj"
                  ]
                  #original: array:6 [
                    "id" => 5458
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "9"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "devjatyj"
                  ]
                  #changes: []
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                  #attributeCastCache: []
                  #dateFormat: null
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                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_publisher" => Illuminate\Database\Eloquent\Collection {#1211
              #items: array:1 [
                0 => App\Models\Term {#1212
                  #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" => 5153
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Просвещение"
                    "field_cases" => null
                    "field_translit" => "prosveschenie"
                  ]
                  #original: array:6 [
                    "id" => 5153
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Просвещение"
                    "field_cases" => null
                    "field_translit" => "prosveschenie"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
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                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_author" => Illuminate\Database\Eloquent\Collection {#1213
              #items: array:4 [
                0 => App\Models\Term {#1214
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:12 [
                    "id" => 4180
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Грачев"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Александр"
                    "field_patronymic" => "Васильевич"
                    "field_surname_rp" => null
                  ]
                  #original: array:12 [
                    "id" => 4180
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Грачев"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Александр"
                    "field_patronymic" => "Васильевич"
                    "field_surname_rp" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
                1 => App\Models\Term {#1215
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:12 [
                    "id" => 5484
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Погожев"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Владимир"
                    "field_patronymic" => "Александрович"
                    "field_surname_rp" => null
                  ]
                  #original: array:12 [
                    "id" => 5484
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Погожев"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Владимир"
                    "field_patronymic" => "Александрович"
                    "field_surname_rp" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
                2 => App\Models\Term {#1216
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:12 [
                    "id" => 3888
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Боков"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Павел"
                    "field_patronymic" => "Юрьевич"
                    "field_surname_rp" => null
                  ]
                  #original: array:12 [
                    "id" => 3888
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Боков"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Павел"
                    "field_patronymic" => "Юрьевич"
                    "field_surname_rp" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
                3 => App\Models\Term {#1217
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:12 [
                    "id" => 4007
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Вишнякова"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Екатерина"
                    "field_patronymic" => "Анатольевна"
                    "field_surname_rp" => null
                  ]
                  #original: array:12 [
                    "id" => 4007
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Вишнякова"
                    "field_bio" => null
                    "field_degree_rp" => null
                    "field_foreign_lang_name" => null
                    "field_foreign_lang_patronymic" => null
                    "field_foreign_lang_surname" => null
                    "field_name" => "Екатерина"
                    "field_patronymic" => "Анатольевна"
                    "field_surname_rp" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1218
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_book_type" => Illuminate\Database\Eloquent\Collection {#1219
              #items: array:1 [
                0 => App\Models\Term {#1220
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:10 [
                    "id" => 6736
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "рабочая тетрадь"
                    "field_book_type_foreign" => null
                    "field_cases" => array:6 [ …6]
                    "field_plural_form" => "рабочие тетради"
                    "field_short_name" => "рт"
                    "field_short_name_foreign" => null
                    "field_translit" => "rabochaya tetrad"
                  ]
                  #original: array:10 [
                    "id" => 6736
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "рабочая тетрадь"
                    "field_book_type_foreign" => null
                    "field_cases" => array:6 [ …6]
                    "field_plural_form" => "рабочие тетради"
                    "field_short_name" => "рт"
                    "field_short_name_foreign" => null
                    "field_translit" => "rabochaya tetrad"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_country" => Illuminate\Database\Eloquent\Collection {#1221
              #items: array:1 [
                0 => App\Models\Term {#1222
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:6 [
                    "id" => 9
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Россия"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "rossiya"
                  ]
                  #original: array:6 [
                    "id" => 9
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Россия"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "rossiya"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_city" => Illuminate\Database\Eloquent\Collection {#1223
              #items: array:1 [
                0 => App\Models\Term {#1224
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:6 [
                    "id" => 15
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Москва"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "moskva"
                  ]
                  #original: array:6 [
                    "id" => 15
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "Москва"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "moskva"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_series" => Illuminate\Database\Eloquent\Collection {#1225
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_umk" => Illuminate\Database\Eloquent\Collection {#1226
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1227
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1228
              #items: array:1 [
                0 => App\Models\Term {#1229
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:10 [
                    "id" => 6706
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "ФГОС (старый)"
                    "field_cases" => array:6 [ …6]
                    "field_color" => null
                    "field_end_year" => "2022"
                    "field_start_year" => "2019"
                    "field_translit" => "fgos-old"
                    "field_type" => null
                  ]
                  #original: array:10 [
                    "id" => 6706
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "ФГОС (старый)"
                    "field_cases" => array:6 [ …6]
                    "field_color" => null
                    "field_end_year" => "2022"
                    "field_start_year" => "2019"
                    "field_translit" => "fgos-old"
                    "field_type" => null
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_publication_number" => "6"
            "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1230
              #items: array:1 [
                0 => App\Models\Term {#1231
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:6 [
                    "id" => 33
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "стереотипное"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "stereotipnoe"
                  ]
                  #original: array:6 [
                    "id" => 33
                    "created_at" => "2026-04-10 13:58:26"
                    "updated_at" => null
                    "name" => "стереотипное"
                    "field_cases" => array:6 [ …6]
                    "field_translit" => "stereotipnoe"
                  ]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [
                    0 => "*"
                  ]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1232
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_under_the_edition_degree" => null
            "field_cover_description" => null
            "field_publication_year" => "2021"
            "field_publication_year_until" => null
            "field_part" => "1, 2, 3"
            "field_part_writing" => "Часть"
            "field_second_foreign_language" => null
            "field_for_whom" => "Учебное издание"
            "field_allowed" => null
            "field_reserve_field" => null
            "field_link_to_source" => null
            "field_tasks_count" => "594"
            "field_priority" => null
            "field_default_folder" => "/fizika_09/grachev-rt/"
            "field_isbn" => "978-5-09-098826-1 (ч.1) 978-5-09-098880-3 (ч.2) 978-5-09-098881-0 (ч.3)"
            "field_cover" => array:3 [
              0 => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
              1 => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
              2 => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
            ]
            "field_cover_alts" => array:3 [
              0 => ""
              1 => ""
              2 => ""
            ]
            "field_covers" => array:3 [
              0 => array:4 [
                "path" => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
                "alt" => ""
                "width" => "2293"
                "height" => "2989"
              ]
              1 => array:4 [
                "path" => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
                "alt" => ""
                "width" => "2265"
                "height" => "3003"
              ]
              2 => array:4 [
                "path" => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                "alt" => ""
                "width" => "2241"
                "height" => "2999"
              ]
            ]
            "field_popular_book" => "0"
            "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1233
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_new_book" => Illuminate\Database\Eloquent\Collection {#1234
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_old_book" => Illuminate\Database\Eloquent\Collection {#1235
              #items: []
              #escapeWhenCastingToString: false
            }
            "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad"
            "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1236
              #items: array:1 [
                0 => App\Models\Term {#1237
                  #connection: "mysql"
                  #table: "terms"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:6 [ …6]
                  #original: array:6 [ …6]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [ …1]
                }
              ]
              #escapeWhenCastingToString: false
            }
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "breadcrumbs" => array:3 [
              "class" => 380
              "subject" => 556
              "class_subject" => 493
            ]
          ]
          #original: array:50 [
            "id" => 1203
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_tree_default_status" => "tasks"
            "field_pages_status" => null
            "field_subject" => Illuminate\Database\Eloquent\Collection {#1207}
            "field_class" => Illuminate\Database\Eloquent\Collection {#1209}
            "field_publisher" => Illuminate\Database\Eloquent\Collection {#1211}
            "field_author" => Illuminate\Database\Eloquent\Collection {#1213}
            "field_author_foreign" => Illuminate\Database\Eloquent\Collection {#1218}
            "field_book_type" => Illuminate\Database\Eloquent\Collection {#1219}
            "field_country" => Illuminate\Database\Eloquent\Collection {#1221}
            "field_city" => Illuminate\Database\Eloquent\Collection {#1223}
            "field_series" => Illuminate\Database\Eloquent\Collection {#1225}
            "field_umk" => Illuminate\Database\Eloquent\Collection {#1226}
            "field_level_of_education" => Illuminate\Database\Eloquent\Collection {#1227}
            "field_standart_of_education" => Illuminate\Database\Eloquent\Collection {#1228}
            "field_publication_number" => "6"
            "field_publication_type" => Illuminate\Database\Eloquent\Collection {#1230}
            "field_under_the_edition" => Illuminate\Database\Eloquent\Collection {#1232}
            "field_under_the_edition_degree" => null
            "field_cover_description" => null
            "field_publication_year" => "2021"
            "field_publication_year_until" => null
            "field_part" => "1, 2, 3"
            "field_part_writing" => "Часть"
            "field_second_foreign_language" => null
            "field_for_whom" => "Учебное издание"
            "field_allowed" => null
            "field_reserve_field" => null
            "field_link_to_source" => null
            "field_tasks_count" => "594"
            "field_priority" => null
            "field_default_folder" => "/fizika_09/grachev-rt/"
            "field_isbn" => "978-5-09-098826-1 (ч.1) 978-5-09-098880-3 (ч.2) 978-5-09-098881-0 (ч.3)"
            "field_cover" => array:3 [
              0 => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
              1 => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
              2 => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
            ]
            "field_cover_alts" => array:3 [
              0 => ""
              1 => ""
              2 => ""
            ]
            "field_covers" => array:3 [
              0 => array:4 [
                "path" => "/media/fizika_09/grachev-rt/covers/cover1.webp?ts=1759003248"
                "alt" => ""
                "width" => "2293"
                "height" => "2989"
              ]
              1 => array:4 [
                "path" => "/media/fizika_09/grachev-rt/covers/cover2.webp?ts=1759003248"
                "alt" => ""
                "width" => "2265"
                "height" => "3003"
              ]
              2 => array:4 [
                "path" => "/media/fizika_09/grachev-rt/covers/cover3.webp?ts=1759003248"
                "alt" => ""
                "width" => "2241"
                "height" => "2999"
              ]
            ]
            "field_popular_book" => "0"
            "field_recommended_books" => Illuminate\Database\Eloquent\Collection {#1233}
            "field_new_book" => Illuminate\Database\Eloquent\Collection {#1234}
            "field_old_book" => Illuminate\Database\Eloquent\Collection {#1235}
            "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad"
            "field_cover_color" => Illuminate\Database\Eloquent\Collection {#1236}
            "field_metatags_title" => null
            "field_metatags_description" => null
            "field_h1" => null
            "field_description_top" => null
            "field_description_bottom" => null
            "breadcrumbs" => array:3 [
              "class" => 380
              "subject" => 556
              "class_subject" => 493
            ]
          ]
          #changes: []
          #casts: []
          #classCastCache: []
          #attributeCastCache: []
          #dateFormat: null
          #appends: []
          #dispatchesEvents: []
          #observables: []
          #relations: []
          #touches: []
          +timestamps: true
          +usesUniqueIds: false
          #hidden: []
          #visible: []
          #fillable: []
          #guarded: array:1 [
            0 => "*"
          ]
        }
      ]
      #escapeWhenCastingToString: false
    }
    "page" => Illuminate\Database\Eloquent\Collection {#1569
      #items: array:1 [
        0 => App\Models\BookPage {#1241
          #connection: "mysql"
          #table: "book_pages"
          #primaryKey: "id"
          #keyType: "int"
          +incrementing: true
          #with: []
          #withCount: []
          +preventsLazyLoading: false
          #perPage: 15
          +exists: true
          +wasRecentlyCreated: false
          #escapeWhenCastingToString: false
          #attributes: array:21 [
            "id" => 1435698
            "created_at" => "2026-04-10 13:58:26"
            "updated_at" => null
            "field_page_start" => "63"
            "field_url" => "/9-klass/fizika/grachev-rabochaya-tetrad/page-3-63"
            "field_display_title" => "63"
            "field_folder" => "3"
            "field_image_name" => "63"
            "field_branch_parent" => Illuminate\Database\Eloquent\Collection {#1245
              #items: array:1 [
                0 => App\Models\Branch {#1244
                  #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
            }
            "field_weight" => "0"
            "field_book_parent" => Illuminate\Database\Eloquent\Collection {#1282
              #items: array:1 [
                0 => App\Models\Book {#1283
                  #connection: "mysql"
                  #table: "books"
                  #primaryKey: "id"
                  #keyType: "int"
                  +incrementing: false
                  #with: []
                  #withCount: []
                  +preventsLazyLoading: false
                  #perPage: 15
                  +exists: true
                  +wasRecentlyCreated: false
                  #escapeWhenCastingToString: false
                  #attributes: array:50 [ …50]
                  #original: array:50 [ …50]
                  #changes: []
                  #casts: []
                  #classCastCache: []
                  #attributeCastCache: []
                  #dateFormat: null
                  #appends: []
                  #dispatchesEvents: []
                  #observables: []
                  #relations: []
                  #touches: []
                  +timestamps: true
                  +usesUniqueIds: false
                  #hidden: []
                  #visible: []
                  #fillable: []
                  #guarded: array:1 [ …1]
                }
              ]
              #escapeWhenCastingToString: false
            }
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№3 (с. 63)
Условие. №3 (с. 63)
скриншот условия
Физика, 9 класс рабочая тетрадь, авторы: Грачев Александр Васильевич, Погожев Владимир Александрович, Боков Павел Юрьевич, Вишнякова Екатерина Анатольевна, издательство Просвещение, Москва, 2021, Часть 2, страница 63, номер 3, Условие

3. Частота звучания чистого музыкального звука ноты «ля» равна 440 Гц. Какой частоты должен быть чистый музыкальный звук, у которого длина волны в воздухе будет равна длине звуковой волны ноты «ля» в воде?

Решение.

Ответ: ___________.

Решение. №3 (с. 63)

Дано:

Частота звука ноты «ля», $f_1 = 440$ Гц

Скорость звука в воде, $v_{вода} \approx 1500$ м/с (справочное значение)

Скорость звука в воздухе, $v_{воздух} \approx 340$ м/с (справочное значение)

Длина волны искомого звука в воздухе $\lambda_2$ равна длине волны ноты «ля» в воде $\lambda_1$.

Найти:

Частоту искомого звука, $f_2$.

Решение:

Длина волны $\lambda$ связана со скоростью ее распространения $v$ и частотой $f$ следующей формулой:

$\lambda = \frac{v}{f}$

1. Сначала найдем длину звуковой волны ноты «ля» ($f_1 = 440$ Гц) при ее распространении в воде. Скорость звука в воде $v_{вода}$.

$\lambda_1 = \frac{v_{вода}}{f_1}$

2. Длина волны второго, искомого, звука с частотой $f_2$ в воздухе (скорость звука $v_{воздух}$) равна:

$\lambda_2 = \frac{v_{воздух}}{f_2}$

3. По условию задачи, эти длины волн равны: $\lambda_1 = \lambda_2$.

Приравняем правые части выражений для длин волн:

$\frac{v_{вода}}{f_1} = \frac{v_{воздух}}{f_2}$

4. Из этого равенства выразим искомую частоту $f_2$:

$f_2 = f_1 \cdot \frac{v_{воздух}}{v_{вода}}$

5. Подставим числовые значения и выполним расчет:

$f_2 = 440 \text{ Гц} \cdot \frac{340 \text{ м/с}}{1500 \text{ м/с}} = 440 \cdot \frac{34}{150} = \frac{14960}{150} \approx 99,73$ Гц.

Округлим полученное значение до десятых.

Ответ: $99,7$ Гц.

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