A particle, held by a string whose other end is attached to a fixed point C, moves in a circle on a horizontal frictionless surface. If the string is cut, the angular momentum of the particle about the point: C.
Correct answer: C. Remains constant
- A. Increases
- B. Decreases
- C. Remains constant
- D. Changes direction but not magnitude
Explanation
Angular momentum is a conserved quantity in the absence of external torques. When the string is cut, the particle continues to move tangentially to its circular path. Since there is no external force or torque acting on the particle with respect to the fixed point C, the angular momentum remains constant.Option A is incorrect because without external torque, angular momentum cannot increase. Option B is incorrect for the same reason-it cannot decrease. Option C is correct because it reflects the principle of conservation of angular momentum. Option D is incorrect because while the particle's trajectory changes, the concept of angular momentum about a point doesn't involve changes in direction without external torque.
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