Question

5. How many kilowatt-hours of energy would be used by a 40 W bulb that runs for 10 hours every

day during the course of one year?

Answer 1

Answer: 146,000 Wh or 146 kWh

Step-by-step explanation:

65 days × 10 hours × 40 W = 146,000 Wh or 146 kWh

Answer 2

E = 0.4 kWh

Step-by-step explanation:

Given that,

The power of a bulb, P = 40 W

Time, t = 10 hours

We need to find the energy used by the bulb. Let it is equal to E. So,

`E=P* t\\\\E=40* 10\\\\E=400\ W-h\\\\or\\\\E=0.4\ kWh`

So, 0.4 kWh of energy would be needed.