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MHT CET 2026 (17 Apr, Shift 2) · Power, Power Factor & Wattless Current

Power, Power Factor & Wattless Current question from MHT CET 2026 (17 Apr, Shift 2)

Q1MHT CET 2026 · 17 APR · SHIFT 2Easy

Power, Power Factor & Wattless Current

In a series LCR circuit alternating e.m.f. and current are given by the equations V=V0sin⁡(ωt)V = V_0\sin(\omega t) and I=I0sin⁡(ωt+π3)I = I_0\sin\left(\omega t + \frac{\pi}{3}\right) respectively. The average power dissipated in the circuit over one cycle of a.c. is (cos⁡60∘=0.5)(\cos 60^\circ = 0.5)

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Answer: (d)

  1. P=VrmsIrmscos⁡ϕ=V0I02cos⁡ϕP = V_{rms}I_{rms}\cos\phi = \frac{V_0I_0}{2}\cos\phi
  2. Phase difference ϕ=π3\phi = \frac{\pi}{3}, cos⁡60∘=0.5\cos 60^\circ = 0.5
  3. P=V0I02×12=V0I04P = \frac{V_0I_0}{2}\times\frac{1}{2} = \frac{V_0I_0}{4}
  4. So the answer is (d) V0I04\frac{V_0I_0}{4}.
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