Two waves of wavelength 2 m and 2.02 m , with the same speed, superimpose to produce 2 beats per second ,The speed of each wave is

Options

A. 400 m/s
B. 404 m/s
C. 402 m/s
D. 406 m/s

Answer

B

Explanation

As `lamda_(2) gt lamda_(1) " " :. n_(1) - n_(2) = 2`
`(v)/(lamda_(1)) - (v)/(lamda_(2)) = 2 " " :. v [(1)/(2) - (1)/(2.02)] =2`
`:. v [(2.02 -2)/(2 xx 2.02)] = 2`
`:. v = (2 xx 2 xx 2.02)/(0.02) = 404 m//s`