Question

A travelling wave passes a point of observation. At this point, the time interval between successive crests is 0.2 seconds and

[MP PMT 1990]

• A. The wavelength is 5 m
• B. The frequency is 5 Hz
• C. The velocity of propagation is 5 m/s
• D. The wavelength is 0.2 m

Answer 1

The correct option is B

The frequency is 5 Hz

Phase difference between two successive crests is $2\pi$. Also, phase deifference $\left(△\varphi \right)=\frac{2\pi }{T}$ time interval $\left(△t\right)$

$\Rightarrow 2\pi =\frac{2\pi }{T}\times 0.2\Rightarrow \frac{1}{T}=5se{c}^{-1}\Rightarrow n=5Hz$