Which of the following examples represent (nearly) simple harmonic motion and which represent periodic but not simple harmonic motion?

(a) the rotation of earth about its axis.

(b) motion of an oscillating mercury column in a U-tube.

(c) motion of a ball bearing inside a smooth curved bowl, when released from a point slightly above the lower most point.

(d) general vibrations of a polyatomic molecule about its equilibrium position.

Asked by Pragya Singh | 1 year ago |  114

1 Answer

Solution :-

(a) Rotation of the earth is not to and fro motion about a fixed point. Therefore, it is periodic but not S.H.M.

(b) Simple harmonic motion

(c) Simple harmonic motion

(d) General vibrations of a polyatomic molecule about its equilibrium position is periodic but not SHM. A polyatomic molecule has a number of natural frequencies. Therefore its vibration is a superposition of simple harmonic motions of a number of different frequencies.

Answered by Abhisek | 1 year ago

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