Question
- Write the mathematical expression for Joule's law of heating.
- Compute the heat generated while transferring 96000 coulomb of charge in two hours through a potential difference of 40V.
✓
Answer
- The mathematical expression of the Joules Law of heating is:
H = I2 Rt
Here, H is a heating effect, I is the current flowing through the device, and t is the time taken
- Given,
Amount of charge transferred = 96000C
Time taken = 2hrs = 2 × 60 × 60sec
= 7200sec
Potential difference = 40V
Heat generated = V × i × t
And we know that;
$\text{i}=\frac{\text{Q}}{\text{t}}$
So, H = VQ
= 40 × 96000
= 3.84 × 106J.
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