Physicshard · Past Paper
Find the heat produced in 1 minute by a heater of 20 Ohms resistance through which 5 A current flows.
A500 J
B30,000 J
C100 J
D6,000 J
✓ Correct Answer: B — 30,000 J
H = I^2 * R * t = 5^2 * 20 * 60 = 25 * 20 * 60 = 30,000 Joules.
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