Question

A transverse pulse is shown in the figure, on which $4$ points are shown at any instant. Which of the following points are in a state to move upwards in subsequent time?

• A. A, B
• B. A, D
• C. B, C
• D. B, D

Answer 1

Answer: (C)

$y=A_{0} \sin (\omega t-k x) $
$\frac{d y}{d t}=V_{P}=A_{0} \omega \cos (\omega t-k x)$
Values for $V_{p}$ at $B$ and $C$ are positive force they are in a state to move upwards.