A sinusoidal progressive wave is generated in a string. It's equation is given by `y = (2mm) sin (2 pi x - 100 pi t + pi//3)` The time when particle at `x = 4 m` first passes through mean position, will be :-

Options

A. `(1)/(150)`s
B. `(1)/(12)` s
C. `(1)/(300)` s
D. `(1)/(100)` s

Answer

C

Explanation

`y=2mm sin(2pix-100pit+(pi)/(3))`
`rArr0=2sin(2pix-100pit+(pi)/(3))`
`rArr npi=8pi-100pit+(pi)/(3)(n=0,1,2,3....)`
`rArr t_(min)=((25pi)/(3)-npi)/(100pi)=(pi)/(3)//100pi=(1)/(300)s`