Предмет: Физика, автор: annav9469

Непрозорий круглий диск освітлюється точковим джерелом світла так, що на екрані утворюється кругла тінь, площа якої у 4 рази перевищує площу непрозорого диску Відстань від джерела світла до непрозорого диска 20 см. Яка відстань від диска до екрана?

555ai555: отношение радиусов 1:2, тогда расстояние от источника до экрана 20*2 = 40 см. тогда от диска до экрана 20 см

Ответы

Автор ответа: lvv9136

Ответ:

20 см

Объяснение:

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