The phase difference between displacement $x$ and velocity $v$ in SHM is:
- 0
- $\pi/4$
- $\pi/2$ (velocity leads displacement by $\pi/2$)
- $\pi$
Show answer and solution
Correct answer: C. $\pi/2$ (velocity leads displacement by $\pi/2$)
$x = A\sin\omega t$ ⇒ $v = A\omega\cos\omega t = A\omega\sin(\omega t + \pi/2)$.
So velocity leads displacement by $\pi/2$ (i.e., $v$ peaks 1/4 period earlier).
Acceleration leads velocity by another $\pi/2$, so $a$ is $\pi$ out of phase with $x$.