The equation of a plane progressive wave travelling along positive direction of `x-`axis is `y=r sin [(2pit)/(T)-(2pix)/(lambda)]` where `y=` displacement of particle at `(x,t),r=` amplitude of vibratio of particle, `T=` time period of wave motion, `lambda=` wavelength of wave ,` x=` starting distance of wave from the origin. Velocity of wave,
`upsilon=vlambda=(lambda)/(T)=` constant.
Acceleration of wave, `a=0`.
Velocity of particle at time `t=(dy)/(dt)`
Acceleration of particle at time `t=(d^(2)y)/(dt^(2))`
Velocity of wave is

Options

A. `2xx10^(3)m//s`
B. `2xx10^(3)cm//s`
C. `2xx10^(4)m//s`
D. `2xx10^(4)cm//s`

Answer

C

Explanation

Velocity of wave, `upsilon=vlambda=(1)/(T)lambda`
`=(80pi)/(pi//250)=80xx250m//s=2xx10^(4)m//s`