Question

An electric device draws an energy of 500 KJ in 1 minute. If the resistance of heating device is 20 ohm, calculate the current flowing through the device.

Answer 1

we know that heat energy dissipated will be

H = I²Rt

or

current will be

I = [H/Rt]^1/2

here,

H = 500 kJ = 500 x 10³ J

R = 20 ohm

t = 1 min = 60s

so,

I = [500 x 10³ / (20 x 60)]^1/2

thus, we get

I = 20.41 amps