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Question
How much heat will an instrument of 12 W produce in one minute if it is connected to the heat produced by it?
Solution
Given: Power rating (P) = 12 W
Time interval (t) = 1 minute = 60 s (1 minute = 60 seconds)
Potential difference (V) = 12 V
Heat = I2Rt
But, we know that P = I2R
Therefore, H = P x t = 12 W x 60 s = 720 joules
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