Question

The wavelength of a wave in medium is $0.5m$. Due to this wave the phase difference between two particles of the medium is $\pi /5$. The minimum distance between these points is

• A. $5km$
• B. $5m$
• C. $5mm$
• D. $5cm$

Answer 1

The correct option is D $5cm$

Given that phase difference is $\frac{\pi }{5}$
For minimum difference in length of the point, assume they lie within the same wavelength.
For a length difference of $\lambda$ phase difference was $2\pi$
For a length difference of $x$ phase difference was $\frac{\pi }{5}$
We find '$x$' to be $\frac{\lambda }{10}$.
Given that wavelength is $0.5m$.
In other words, $x$ is $5cm$.