Physics Circle home Student Login

Home›Chapters›Alternating Current PYQs›Resonance, Bandwidth & Q Factor›Question 56

JEE Main 2023 (25 Jan, Shift 1) · Resonance, Bandwidth & Q Factor

Resonance, Bandwidth & Q Factor question from JEE Main 2023 (25 Jan, Shift 1)

Q56JEE Main 2023 · 25 JAN · SHIFT 1Easy

Resonance, Bandwidth & Q Factor

An LCR series circuit of capacitance 62.5 nF and resistance of 50 Ω\Omega, is connected to an A.C. source of frequency 2.0 kHz. For maximum value of amplitude of current in circuit, the value of inductance is __________ mH.

(Take π2=10\pi^2 = 10)

Numerical answer type. Work it out, then open the answer.

Show answer and solution

Answer: 100

  1. Maximum current amplitude at resonance: L=14π2f2CL = \dfrac{1}{4\pi^2 f^2 C}
  2. 4π2f2C=40×(2×103)2×62.5×10−9=40×4×106×62.5×10−9=104\pi^2 f^2 C = 40 \times (2\times10^3)^2 \times 62.5\times10^{-9} = 40 \times 4\times10^6 \times 62.5\times10^{-9} = 10
  3. L=110=0.1 H=100 mHL = \dfrac{1}{10} = 0.1\text{ H} = 100\text{ mH}
  4. So the answer is 100 mH.
Report a mistake

More questions on Resonance, Bandwidth & Q Factor