An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s

Question

An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s.

Answer 1

The amount of heat (H) produced is given by the joule's law of heating asH= Vlt
Where,
Current, I = 5 A
Time, t = 30 s
Voltage, V = Current x Resistance = 5 x 20 = 100 V

H= 100 x 5 x 30 = 1.5 x 10⁴ J.

 

Therefore, the amount of heat developed in the electric iron is 1.5 x 10⁴ J.