Question

How many seconds would it take for a 4.50kw motor to raise a 175.kg boiler to a height of 15.0m?

Answer 1

Given:

$P=4.50\:\rm kW$

$m=175\:\rm kg$

$h=15.0\:\rm m$

The required time

$$t=\frac{W}{P}=\frac{mgh}{P}=\frac{175*9.8*15.0}{4500}=5.72\:\rm s$$