Q 11-14-070JEE MainJEE Main 2022 (24 Jun, Shift 2)Easy
Two travelling waves of equal amplitudes and equal frequencies move in opposite directions along a string. They interfere to produce a stationary wave whose equation is given by $y = \left(10\cos\pi x\sin\dfrac{2\pi t}{T}\right)\ \text{cm}$. The amplitude of the particle at $x = \dfrac43\ \text{cm}$ will be ______ cm.
Numerical value type. Enter your answer.
Answer: 5
The amplitude at position $x$ is $|10\cos\pi x|$:
$$A = \left|10\cos\frac{4\pi}{3}\right| = 10\times\frac12 = 5\ \text{cm}$$
Solution by Sreeraj P, M.Sc Physics