The equation of the stationary wave is
`y = 2 A sin (( 2 pi c t)/( lambda)) cos (( 2 pi x)/( lambda))`
Which of the following statements is wrong?

Options

A. The unit of ct is same as that of `lambda`.
B. The unit of x is same as that of `lambda`.
C. The unit of `2pic//lambda` is same as that of `2pix//lambda t`.
D. The unit of `2pic//lambda` is same as that of `2pix//lambda t`.

Answer

D

Explanation

Here `(2 pict//lambda)` as well as. `(2 pi x// lambda)` are demensionless. So, unit of ct is same as that of `lambda`.
Since, `[(2pi ct)/(lambda)] = [(2pi x)/(lambda)] = [M^(0)L^(0)T^(0)]`
Hence , `(2pic)/(lambda) = (2pix)/(lambda t)`
In the option (d). `x/lambda` is unitless. it is not the case with `c/(lambda)`.