Question

The diagram below shows an instantaneous position of a string as a transverse progressive wave travels along it from left to right.
Which one of the following correctly shows the direction of the velocity of the points $1,2$ and $3$ on the string?

• A. Diagram
• B. Diagram
• C. Diagram
• D. Diagram

Answer 1

The correct option is B Diagram

As we know,
particle velocity $\left(v_P\right)=-v\times$ slope of the graph at that point
Hence, as per the question,
At point $1:$ Slope of the curve is positive; hence particle velocity is negative or downward $(\downarrow )$.
At point $2:$ Slope is negative; hence particle velocity is positive or upward $(\uparrow )$.
At point $3:$ Again, slope of the curve is positive, hence particle velocity is negative or downward $(\downarrow )$.

Final answer: (d)