Предмет: Физика, автор: ЖенёкПенёк

Какая работа совершается при подъёме мраморной плиты объёмом 2м3 на высоту 12 м ? какую мощность развивают при этом , если плиту поднимают за 2 мин ? Плотность мрамора 2,7 г / см3

Ответы

Автор ответа: kirills1

1) A = F * S

F - сила
S - путь ( 12 м )

F = m * g

m - масса
g - ускорение свободного падения ( 10 Н / кг )

m = p * V

p - плотность ( 2700 кг / м³ )
V - объём ( 2 м³ )

m = 2700 * 2 = 5400 кг

F = 5400 * 10 = 54000 H

A = 54000 * 12 = 648000 Дж = 648 кДж

2) N = $\frac{A}{t}$

A - работа ( 648000 Дж )
t - время ( 2 мин = 120 с )

N = $\frac{648000}{120}$ = 5400 Вт = 5,4 кВт

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