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A level physics SHM mcq help

A particle, whose equilibrium position is at Q, is set into oscillation by being displaced to P, 50 mm from Q, and then released from rest. Its subsequent motion is simple harmonic, but subject to damping. On the first swing, the particle comes to rest momentarily at R, 45 mm from Q.

During this first swing, the greatest value of the acceleration of the particle is when it is at
A) P.
B)Q.
C) R.
D) P and R.

Can someone please explain why the answer is A?
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Original post by 1234kelly
A particle, whose equilibrium position is at Q, is set into oscillation by being displaced to P, 50 mm from Q, and then released from rest. Its subsequent motion is simple harmonic, but subject to damping. On the first swing, the particle comes to rest momentarily at R, 45 mm from Q.

During this first swing, the greatest value of the acceleration of the particle is when it is at
A) P.
B)Q.
C) R.
D) P and R.

Can someone please explain why the answer is A?

The driving force/acceleration for shm is proportional to displacement so P. The damping term will have no affect as it depends on velocity which is zero at P (and R).

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