Question

In the above question, if both are in opposite direction, then the velocity of the pulse with respect to ground will be:

• A.
• B.
• C.
• D.

Answer 1

The correct option is D

Velocity of rope w.r.t. ground will be $V_{RG}=\omega R=\frac{-\omega L}{2\pi }$ ( Negative sign indicates that pulse velocity and rope velocity are in opposite direction)
As obtained in the previous question, the velocity of pulse w.r..t. rope is given by,
$V_{PR}=\frac{\omega L}{2\pi }{V}_{PR}=V_{PG}-V_{RG}=\frac{\omega L}{2\pi }\Rightarrow V_{PG}-\frac{-\omega L}{2\pi }=\frac{\omega L}{2\pi }\therefore V_{PG}=0$