Classical Mechanics - Harmonic Oscillator

A particle of mass m undergoes harmonic oscillation with period T0. A force f proportional to the speed v of the particle, fbv, is introduced. If the particle continues to oscillate, the period with f acting is

A. Larger than T0
B. Smaller than T0
C. Independent of b
D. Dependent linearly on b
E. Constantly changing
(GR9677 #08)

Solution:

 f = bv → minus sign means f is restoring force (damped oscillation).
The oscillation is getting slower (larger period) before it finally comes to stop.

Answer: A

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