Work and Energy — Question 14

Given,

Power of the heater = 1500 W

Converting W to kW

1000 W = 1 kW

So, 1500 W = $\dfrac{1500}{1000}$ = 1.5 kW

Time taken = 10 h

We know,

Power = $\dfrac{\text{Energy consumed}}{\text{Time taken}}$

Or

Energy consumed = Power x Time taken

Substituting we get,

Energy consumed = 1.5 x 10 = 15 kWh

Converting kWh to J

1 kWh = 3.6 x 10⁶ J

So, 15 kWh = 3.6 x 10⁶ x 15 = 5.4 x 10⁷ J

Hence, the energy consumed = 5.4 x 10⁷ J