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MHT CET 2025 (19 Apr, Shift 2) · Power, Power Factor & Wattless Current

Power, Power Factor & Wattless Current question from MHT CET 2025 (19 Apr, Shift 2)

Q24MHT CET 2025 · 19 APR · SHIFT 2Medium

Power, Power Factor & Wattless Current

In an L−RL - R circuit, the inductive reactance is equal to 3\sqrt{3} times the resistance ' RR ' of the circuit. An e.m.f. E=E0sin⁡(ωt)E = E_0 \sin(\omega t) is applied to the circuit. The power consumed in the circuit is

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Answer: (c)

  1. XL=3RX_L = \sqrt{3}R, so Z2=R2+3R2=4R2Z^2 = R^2 + 3R^2 = 4R^2.
  2. P=Erms2RZ2=E022⋅R4R2P = \frac{E_{rms}^2R}{Z^2} = \frac{E_0^2}{2} \cdot \frac{R}{4R^2}.
  3. P=E028RP = \frac{E_0^2}{8R}.
  4. So the answer is (c) E028R\frac{E_0^2}{8R}.
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