Question

Utility companies charge by the kilowatt-hour. The number of kilowatt-hours used equals the number of kilowatts multiplied by the number of hours an electrical device was used. How long would it take for a 50-watt fan to use 1 kilowatt-hour of electricity? (Hint: 50 watts = 0.05 kilowatts.)

Answer 1

Answer:

t = 3 minutes

Explanation:

Given that,

Power of fan, P = 50 W

Energy used, E = 1 kWh

We know that,

Energy = Power/time

As, 50 watts = 0.05 kilowatts

So,

$t=\dfrac{P}{E}\\\\t=\dfrac{0.05\ kW}{1\ kWh}\\\\t=0.05\ h$

or

t = 3 min

So, the required time is equal to 3 minutes.