Question

A particle executes SHM along x-axis about the centre x= -a with a frequency f Hz. Initially the particle at rest at the origin. Its equation of motion will be :

• A. (a) x = 2a(1-cos2$\pi$ ft)
• B. (b) x = a(cos2$\pi$ ft)
• C. (c) x = a(cos2$\pi$ ft-1)
• D. (d) x = a(1-cos2$\pi$ ft)

Answer 1

The correct option is C (c) x = a(cos2$\pi$ ft-1)

At extreme position K.E of SHM is zero,then origin will be one extreme position.

Therefore equation of motion will be,

$x=-a+a\cos \left(2\pi ft\right)=a(\cos 2\pi ft-1)$