Physics · Simple Harmonic Motion

JEE Advanced 2024 — Paper 1 — Question 20

Two beads, each with charge qq and mass mm, are on a horizontal, frictionless, non-conducting, circular hoop of radius RR. One of the beads is glued to the hoop at some point, while the other one performs small oscillations about its equilibrium position along the hoop. The square of the angular frequency of the small oscillations is given by [ ε0\varepsilon_{0} is the permittivity of free space.]

  1. Option A:

    q2/(4πε0R3m)q^{2} /\left(4 \pi \varepsilon_{0} R^{3} m\right)

  2. Option B:

    q2/(32πε0R3m)q^{2} /\left(32 \pi \varepsilon_{0} R^{3} m\right)

    Correct
  3. Option C:

    q2/(8πε0R3m)q^{2} /\left(8 \pi \varepsilon_{0} R^{3} m\right)

  4. Option D:

    q2/(16πε0R3m)q^{2} /\left(16 \pi \varepsilon_{0} R^{3} m\right)

Answer: B

Step-by-step solution

So, at=a_{t}= tangential acceleration of bead =kqq2sin⁡(θ2)4mR2cos⁡2(θ2)=\frac{k q q^{2} \sin \left(\frac{\theta}{2}\right)}{4 m R^{2} \cos ^{2}\left(\frac{\theta}{2}\right)} So, at≈kq24mR2(θ2)=q2x32πε0R3 m\mathrm{a}_{\mathrm{t}} \approx \frac{\mathrm{kq}^{2}}{4 \mathrm{mR}^{2}}\left(\frac{\theta}{2}\right)=\frac{\mathrm{q}^{2} \mathrm{x}}{32 \pi \varepsilon_{0} \mathrm{R}^{3} \mathrm{~m}}

Solution figure

Answer key and solution verified before publishing.

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Exam
JEE Advanced 2024
Paper
Paper 1
Subject
Physics
Chapter
Simple Harmonic Motion
Topic
Forced and Damped Oscillations
Two beads, each with charge q and mass m , are on a horizontal… | JEE Advanced 2024 PYQ with Solution · DhiX AI