Q19 of 330 Page 66

A resistance of 25 Ω is connected to a 12 V battery. Calculate the heat energy in joules generated per minute.

Here R = 25ohms, V = 12V, H = ?, t = 60sec

According to Ohm’s law


V = IR


12 = 25XI


I = 0.48amp


We know that according to Joule's law of heating


H = I2RT


H = 0.482X25X60


H = 345.6J


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