Part of SHM is graphed in the figure. Here, `y` is displacement from mean position. The correct equation describing the SHM is

Options

A. `y = 4 cos (0.6t)`
B. `y = 2 sin ((10)/(3)t - (pi)/(2))`
C. `y = 2sin ((pi)/(2) - (10)/(3) t)`
D. `y = 2 cos (0.6 t + (pi)/(2))`

Answer

B

Explanation

`T = 0.6pi`
`:. omega = (2pi)/(T) = (2pi)/(0.6pi)`
`= (10)/(3) rad//s`
Particle starts from `y = - A = - 2 cm`
`:. y = - Acos omega t`
`= A sin (omega t - pi//2)`
` = 2sin ((10)/(3)t - pi//2)`.