Question
How much energy is consumed when a current of 5 amperes flows through the filament (or element) of a heater having resistance of 100 ohms for two hours? Express it in joules.
✓
Answer
I = 5 amp, R = 100 ohms, t = 2h
We know that
Electric energy consumed = P x t = I * I * Rt
= 25 × 100 × 2
= 5000Wh
= 5kwh
We know that 1kwh = 3.6 × 106J
Therefore, 5kwh = 5 × 3.6 × 106J = 18 × 106J.
We know that
Electric energy consumed = P x t = I * I * Rt
= 25 × 100 × 2
= 5000Wh
= 5kwh
We know that 1kwh = 3.6 × 106J
Therefore, 5kwh = 5 × 3.6 × 106J = 18 × 106J.
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