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Paragraph: A smooth circular wire track of radius R and mass m is lying in gravity free space. Two small conduting rings each of charge +q and mass m which can slide freely on circular track are released from rest when shortest distance between them is ' R ' as shown in figure. At the instant when the two rings come to diametrically opposite points Question: Velocity of wire track is

Options

  1. Aq^2 6 ₀ m R
  2. Bq 24 ₀ mR
  3. Cq 8 ₀ mR
  4. Dq 16 ₀ mR

Correct answer

A. q^2 6 ₀ m R

Step-by-step solution

From conservation of momentum along y-direction 0= mV -2 mv ~V =2 v Now using energy conservation aligned & q^2 4 ₀ R = 1 2 m 4 v^2+ 1 2 mv ^2 2+ q ^2 4 ₀(2 R ) v = q ^2 24 ₀ mR & ~V =2 v aligned

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