Question

v = nd
d id wavelength​

Answer 1

as we know,

$speed = \frac{ditance}{time}$

or

$v = \frac{s}{t} - - - (1)$

where, s=distance. v=speed. t=time

and,

$frequency = \frac{1}{time}$

or

$n = \frac{1}{t}$

or

$t = \frac{1}{n} - - - (2)$

where, n=frequency t=time

and,

wavelength is the distance covere by wave in one oscillation=d=s---------(3)

by using eq. 1,2 and 3,

$v = nd$

hence proved