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MHT CET 2026 (15 May, Shift 2) · AC Basics: Peak, RMS & Average Values

AC Basics: Peak, RMS & Average Values question from MHT CET 2026 (15 May, Shift 2)

Q2MHT CET 2026 · 15 MAY · SHIFT 2Easy

AC Basics: Peak, RMS & Average Values

An AC source is 120120 V - 6060 Hz. The value of voltage after 1720\frac{1}{720} s from start will be (sin⁡30∘=12)\left(\sin 30^\circ = \frac{1}{2}\right)

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Answer: (c)

  1. Rated 120120 V is the rms value, so V0=1202≈169.7V_0 = 120\sqrt{2} \approx 169.7 V.
  2. ωt=2π×60×1720=π6\omega t = 2\pi \times 60 \times \frac{1}{720} = \frac{\pi}{6}
  3. V=V0sin⁡π6=169.7×12≈84.8V = V_0 \sin\frac{\pi}{6} = 169.7 \times \frac{1}{2} \approx 84.8 V
  4. So the answer is (c) 84.884.8 V.
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