How much energy is consumed when a current of 5 amperes flows through the filament (or element) of a heater having resistance of 100 ohms for two hours? Express it in joules.
Here, current (I) = 5amp, Resistance(R) = 100 ohms and time = 2h
As we know that
Electric energy consumed = P x t = I2Rt
= 52 x 100 x 2
= 5000 Wh
= 5 kwh
We know that
1kwh = 3.6 x 106 J
Therefore, 5kwh = 5 x 3.6 x 106 J = 18 x 106 J