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MHT CET20226 Aug 2022Evening ShiftPhysicsRotational MotionActual

Two circular loops P and Q of radii r and n r respectively are made from a uniform wire. Moment of inertia of Q about its axis is four times that of P about its axis. The value of n is

Options

  1. A(2)^ 2 3
  2. B(2)^ 1 3
  3. C2
  4. D2

Correct answer

A. (2)^ 2 3

Step-by-step solution

Given, I_Q=4 I_P . Let m be the mass per unit length of wire. m 2 n r(n r)^2=4 [(m 2 r) r^2 ] Implies n^3=4 n=4^ 1 / 3

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