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


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