Question

A lawnmower engine running for 20 min does 4,560,000 J of work. What is the power output of the engine? (Power: P = W/t)

3800 W
228,000 W
91,200,000 W
547,200,000 W

Answer 1

The answer is 3800 watt

Answer 2

The correct answer to the question is 3800 watt. i.e the power of the engine is 3800 watt .

CALCULATION:

As per the question, the running time of the engine t = 20 min.

We know that 1 minute = 60 seconds.

Hence, 20 min = 20 × 60 seconds

= 1200 seconds.

The work done by the engine W = 4,560,000 J.

We are asked to calculate the power of the engine.

The power of the engine is defined as the work done by the engine per unit time.

Mathematically power P =
`(W)/(t)`

=
`(4,560,000)/(1200) Js^(-1)`

=
`3800\ watt.`

= 3800 W [ANS]

Here, watt (W) is the unit of power and 1 watt =
`1\ Js^(-1)`

Hence, the power of the engine is 3800 watt.