NEET-XII-Physics
12: Simple Harmonic Motion
- #1A student says that he had applied a force
F=-kxon a particle and the particle moved in simple harmonic motion. He refuses to tell whether k is a constant or not. Assume that he was worked only with positive x and no other force acted on the particle.
(a) As x increases k increases.
(b) As x increases k decreases.
(c) As x increases k remains constant.
(d) The motion cannot be simple harmonic.digAnsr: aAns : (a) As x increases k increases.
A body is said to be in simple harmonic motion only when,
F = `` -`` kx ...(1)
where F is force,
k is force constant, and
x is displacement of the body from the mean position.
Given:
F = -k`` \sqrt{x}`` ...(2)
On comparing the equations (1) and (2), it can be said that in order to execute simple harmonic motion, k should be proportional to `` \sqrt{x}`` . Thus, as x increases k increases.
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