Question

An engine raises 100 kg of water through a height of 60m in 20 seconds. What is the power of the engine(take g as 10ms-2)

Answer 1

In order to raise $m = 100kg$ of water through the height $h = 60m$ the following amount of work is required:

$$W = mgh$$

By definition, the power is:

$$P = \dfrac{W}{t} = \dfrac{mgh}{t}$$

where $t= 20s$ is the time reqired to do the work.

Thus, obtain:

$$P = \dfrac{100kg\cdot 10m/s^2\cdot 60m}{20s} = 3000W$$

Answer. 3000 W.