Question

An electric iron resistance 20 ohm takes a current of 50 ampere ampere then the heat developed in 30 seconds will be

Answer 1

by joules law of heating

h=i^2×r×t

h=50×50×20×30

h=1500000 joules of energy is released

Answer 2

h=I2RT
(50)2×20×30
2500×20×30
50000×30
1500000joule