Question

Surface waves strike the rock with their crests $160m$ apart. The velocity of the wave is $40m{s}^{-1}$, The time interval between two crests striking the rock is

• A. $8s$
• B. $4s$
• C. $2s$
• D. $1s$

Answer 1

The correct option is B $4s$

Given,

The distance between crest is called wavelength.

$\lambda =160\text{m}$

$\text{velocity(v)}=40m{s}^{-1}$

so,

$\text{time(t)}=\frac{\lambda }{v}$

$\Rightarrow t=\frac{160}{40}$

$\Rightarrow t=4\text{s}$