If the equation of progressive wave is given by `y=4 sin pi[(t)/(5)-(x)/(9)+(pi)/(6)]` then, which of the following is correct `?` (Assume SI units )

Options

A. `upsilon=5cm//s`
B. `r=0.04cm`
C. `lambda=18m`
D. `v=50Hz`

Answer

C

Explanation

Given equation is `y=4sinpi[(t)/(5)-(x)/(9)+(pi)/(6)]`
`=4sin [(pi)/(5)-(pix)/(9)+(pi^(2))/(6)]`
Comparing the given equation with
`y=rsin[(2pi)/(T)t-(2pi)/(lambda)x+phi_(0)]`
we get `,l-(2pi)/(lambda)=(-pi)/(9)` or `lambda=18m`