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MHT CET20225 Aug 2022Morning ShiftPhysicsRotational MotionActual

A mass tied to a string is whirled in a horizontal circular path with a constant angular velocity and its angular momentum is L. if the string is now halved, keeping angular velocity same, then the angular momentum will be

Options

  1. AL
  2. BL 4
  3. C2 ~L
  4. DL 2

Correct answer

B. L 4

Step-by-step solution

The correct option is (B). Concept: Angular momentum is given by L = m r ^2 , where m is the mass, the angular velocity and r is the radius of the circular motion (length of the string). If the new length is half of the original string, then the new angular momentum would be, L _ n = m ( r 2 )^2 Or L _ n = ( M r ^2 )= 1 4 = L 4

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