A plane progressive wave of frequency 25 Hz, amplitude `2.5 xx 10^(-5) m` and initial phase zero moves along the negative x-direction with a velocity of 300 m/s. A and B are two points 6 m apart on the line of propagation of the wave. At any instant the phase different between A and B is `phi`. The maximum difference in the displacements of particle at A and B is `Delta`

Options

A. `(pi)/(2) " rad" 0.5 xx 10^(-5) m`
B. `(pi)/(3) " rad" 10^(-5) m`
C. `(pi)/(4)` rad and zero
D. `pi` rad and zero

Answer

D

Explanation

`v = 300 m//s and r = 25 Hz`
`:. lamda = (v)/(f) = (300)/(25) = 12 m`
(i) Phase difference `= (2pi)/(lamda)` (path difference)
`= (2pi)/(12) xx (6)/(1) = pi`
(ii) In a plane progressive wave, the amplitude remains constant.
`:.` Change in amplitude is zero