Question

A man sitting on the beach watching water waves sees 4 waves pass by in 2 seconds, each with a wavelength of 0.5m. Find out the speed of the waves ?

• A. 0.25 m/s
• B. 0.5 m/s
• C. 1.0 m/s
• D. 2.0 m/s
• E. 4.0 m/s

Answer 1

Answer: (C)

1.0 m/s

Given : $t=2$ s $\lambda =0.5$ m

Number of waves passing in 2 s $N=4$

Thus frequency of wave $\nu =\frac{N}{t}=\frac{4}{2}=2$ Hz

Speed of the wave $v=\lambda \times \nu =0.5\times 2=1.0$ m/s