How much heat will an instrument of 12 W produce in one minute if it is connected to a battery of 12 V?
Here, it is given that P = 12W, V = 12V, t = 60sec
We know that
P = VI
I = P/V = 12/12 = 1A
Again, we know that
V = IR
R = V/I = 12/1 = 12ohm
So according to the Joule’s heating law, we know that
H = I2Rt
H = 12x12x60
H = 720J