Question 18.

**Solve the example.Who will spend more electrical energy? 500 W TV Set in 30 mins, or 600 W heater in 20 mins?**

Answer:

We know Energy spent = P x t

Where P = power

t = time

in case of tv set

P = 500 W

t = 30 minutes = 1/2 hour

so, energy spent = 500 x 1/2

= 250 Wh

In case of heater

P = 600 W

t = 20 minutes = 0.33 hour

so, energy spent = 600 x 0.33

= 198 Wh

Hence TV set spent more electrical energy.