The pattern of standing waves formed on a stretched string at two in -stants of time are shown of time are shown in figure. The velocity of two waves superim-posing to form stationary waves is `360 ms^(-1)` and their frequencies are 256 Hz.

(a) Calculate the time at which the second curve is plotted.
(b) Mark nodes and antinodes on the curve.
(c) Calculate the distance between A' and C'

Explanation

Given , frequency of the wave v=256 Hz
Time period `" " T=(1)/(v)=(1)/(256)s=3.9xx10^(-3)=s`
(a) Time taken to pass through mean position is
`" " t=(T)/(4)=(1)/(40)=(3.9xx10^(-3))/(4)s=9.8xx10^(-4)s`
(b) Nodes are A,B,C,D,E (i.e., zero displacment )
Antinodes are A',C' ( i.e., maximum displacement )
(c) It is clear from the diagram A' and C' are consecutive hence seperation =wavelength `(lambda)`
`" " =(v)/(v)=(360)/(256)=1.41m`