Предмет: Физика, автор: mariykapitelMasha

ДОПОМОЖІТЬ. ДАЮ 35 БАЛІВ!!

За допомогою нерухомого блоку піднімають вантаж масою 70 кг на висоту 2 м прикладаючи до вільного кінця мотузки 800 Н. Яку роботу при цьому виконують? Який ККД блока?

Ответы

Автор ответа: DedStar

Ответ:

Объяснение:

Полезная работа:

A₁ = m·g·h = 70·10·2 = 1 400 Дж

Совершенная работа:

A₂ = F·h = 800·2 = 1 600 Дж

КПД = А₁·100%/А₂ = 1 400·100% / 1 600 =87,5 %

mariykapitelMasha: Велике дякую , допомогли)

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