Which one of the following is correct?
One unit of electric power is consumed when

Options

A. 1 A of current flows for 1 sec at 220 V
B. 1 A of current flows for 1 sec at 10 V
C. 100 A of current flows for 1 sec at 10 V
D. 10 A of current flows for 1 hour at 100 V

Answer

D

Explanation

One unit of electric power =kWh=1000 watt hour
`P=V.I.t=100vxx10Axx1" hour "=1000" W hour"`
Thus 10 A of current flowing for 1 hour at 100 V is equal to one unit of electric power.