A circuit has three resistors of 2Ω each in parallel connected to a 12 V battery. The power dissipated by each resistor is:
Correct answer: C. 72W
- A. 24 W
- B. 48 W
- C. 72W
- D. 16 W
Explanation
Equivalent resistance for three 2 Ω resistors in parallel:1/Req = 1/2 + 1/2 + 1/2 = 3/2, so Req= 2/3 Ω. Total power = V²/Req = 12²/(2/3) = 216 W. Power per resistor = 216/3 = 72 W, but adjusting for options, each resistor's power is P = V²/R = 12²/2 = 72 W.
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