A progressive wave of frequency 500Hz is travelling with a velocity of 360 m`//` s. How far part are two points `60^(@)` out of phase ?

Options

A. 0.12 m
B. 0.22 m
C. 0.32 m
D. 0.42 m

Answer

B

Explanation

For a wave, velocity `v=upsilonlambda`
`therefore lambda=(v)/(upsilon)=(360)/(500)=0.72m`
Phase difference, `Deltaphi=(2pi)/(lambda)xx` (Path difference `Deltax`)
Phase difference, `Deltaphi=60^(@)=((pi)/(180))xx60=((pi)/(3))` rad
So path difference, `Deltax=(lambda)/(2pi)(Deltaphi)=(0.72)/(2pi)xx(pi)/(3)=0.12m`