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NEET2019PhysicsRotational MotionActual

Assertion : For a system of particles under central force field, the total angular momentum is conserved. Reason : The torque acting on such a system is zero.

Options

  1. AIf both assertion and reason are true and reason is the correct explanation of assertion.
  2. BIf both assertion and reason are true but reason is not the correct explanation of assertion.
  3. CIf assertion is true but reason is false.
  4. DIf both assertion and reason are false.

Correct answer

B. If both assertion and reason are true but reason is not the correct explanation of assertion.

Step-by-step solution

When external torque acting on the system is zero then only the total angular momentum of system is considered to be conserved. = d L d t If =0, d L d t =0 L =I = constant

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