Question

The angle between wave velocity and particle velocity in a travelling wave may be

• A. Zero
• B. $\frac{\pi }{2}$
• C. $\pi$
• D. All of these

Answer 1

The correct option is D All of these

For longitudinal travelling wave, angle between wave velocity and particle velocity is either zero or $\pi$.
For transverse travelling wave, angle between wave velocity and particle velocity is $\frac{\pi }{2}$.
Thus, option (d) is the correct answer.