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Question
An electric iron of resistance 20 Ω draws a current of 5 A. The heat developed in the iron in 30 seconds is ______.
Options
15000 J
6000 J
1500 J
3000 J
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Solution
An electric iron of resistance 20 Ω draws a current of 5 A. The heat developed in the iron in 30 seconds is 15000 J.
Explanation:
I = 5 A, R = 20 Î and t = 30 s
H = I2Rt = 52 x 20 x 30 = 25 x 20 x 30 = 15000 J
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