Question

An LED bulb of 5 W power is used for 1 hr. How much electrical energy is used by the bulb? *

Answer 1

To consume 1 unite electricity energy, 1000 watt energy consume required, in period of one hour.

And, any appliance with 5 watt rating means it consume 5 watt per hour.

So, your answer is

1000/5=200

Thus, 200 hour required by 5 watt LED bulb to consume 1 unite.