JEE PYQ: Oscillations Question 14
Question 14 - 2021 (25 Feb 2021 Shift 2)
$Y = A\sin(\omega t + \phi_0)$ is the time-displacement equation of a SHM. At $t = 0$ the displacement of the particle is $Y = \frac{A}{2}$ and it is moving along negative $x$-direction. Then the initial phase angle $\phi_0$ will be:
(1) $\frac{\pi}{6}$
(2) $\frac{\pi}{3}$
(3) $\frac{5\pi}{6}$
(4) $\frac{2\pi}{3}$
Show Answer
Answer: (4)
Solution
$\sin\phi_0 = 1/2$ gives $\phi_0 = \pi/6$ or $5\pi/6$. Since velocity is negative, $\cos\phi_0 < 0$. So $\phi_0 = 5\pi/6$.
BETA
