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Question
Name the factors on which the heat produced in a wire depends when current is passed in it, and state how does it depend on the factors stated by you.
Solution
Factors on which heat produced depends:
- On the current of wire: The square of the current l flowing through the wire is directly proportional to the heat H produced by the wire, i.e. H ∝ I2.
- On the resistance of wire: The wire's resistance, R, is directly proportional to the heat, H, that it generates. i.e. H ∝ R.
- On time: The quantity of heat H generated in the wire is proportionate to the duration t. during which current flows through it. i.e. H ∝ t.
From the above, H ∝ I2Rt or H =0.24 I2Rt.
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