Предмет: Физика, автор: sopham

СРОЧНО ПОМОГИТЕ
с помощью недвижимого блока поднимают груз массой 15 кг. найдите силу которую прикладывают чтобы поднять груз, если КПД блока равен 85%

Ответы

Автор ответа: vlad5748
0

Ответ:

F=176,47 Н

Объяснение:

η=85%

m=15 кг

F=?

η=(Ап/Аз)*100=[m*g*h/(F*S)]*100, т.к. блок неподвижный, то h=S ⇒ η=[m*g*/F]*100 ⇒ F=100*m*g/η=100*15*10/85≈176,47 Н

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