Two waves are approaching each other with a velocity of `20m//s` and frequency `n`. The distance between two consecutive nudes is

Options

A. `20/n`
B. `10/n`
C. `5/n`
D. `n/10`

Answer

B

Explanation

The two waves of the same frequency and travelling with the same velocity in opposite directions, form a standing wave, in which nodes and antinodes are formed .The distance between two consecutive nodes ` = lambda/2`
But `lambda = v/n = 20/n :. lambda/2 = 20/(2n) = 10/n`