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In an a.c. circuit voltage and current are given by : V = 100 sin (100 t) V and I = 100 sin (100 t + \u03c0/3) mA respectively. The average power dissipated in one cycle is :
- 25 W
- 2.5 W
- 10 W
- 5 W
Correct answer: 2.5 W
Solution
The average power in an AC circuit can be calculated using the formula P = VI cos(φ), where φ is the phase difference between voltage and current. Here, the voltage is 100 V, the current is 0.1 A (100 mA), and the phase difference is π/3, leading to an average power of 2.5 W.
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