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30 БАЛЛОВ!
Мотор экскаватора имеет мощность 14,7 кВт. За час экскаватор поднял 500 т земли на высоту 1 м. Каков коэффициент полезного действия экскаватора?
Принять g=9.8[tex]\frac{H}{kg}[/tex].
Ответ (округлить до целого числа): η≈ [ответ] %.
Ответы 1
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Ответ:
Объяснение:
кпд=m*g*h/N*t=500*10^3*9,8*1*100%/14,7*10^3*3600=9%
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Автор:
harleyrm8i - 5 лет назад
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Предмет:
Английский язык -
Автор:
luna62 - 5 лет назад
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