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JEE Advanced2007PhysicsRotational MotionActual

Paragraph: P _ 17 - 19 : Paragraph for Questions Nos. 17 to 19 Two discs A and B are mounted coaxially on a vertical axle. The discs have moments of inertia I and 2I, respectively about the common axis. Disc A is imparted an initial angular velocity 2 using the entire potential energy of a spring compressed by a distance x₁ . Disc B is imparted an angular velocity by a spring having the same spring constant and compr

Options

  1. A2 I 3 t
  2. B9 I 2 t
  3. C91 4 t
  4. D3 I 2 t

Correct answer

A. 2 I 3 t

Step-by-step solution

Let ^ be the common velocity. Then from conservation of angular momentum, we have aligned (i+2 I) ^ & =I(2 )+2 I( ) ^ & = 4 3 aligned From the equation, Angular impulse = change in angular momentum for any of the disc, we have aligned t & =I(2 )-I ( 4 3 )= 2 I 3 & = 2 I 3 t aligned Option (a) is correct.

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