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JEE Main 26 August 2021, Shift 2, Physics Q30

Question 30 of 90 in this shift, Physics question 30 of 30, Section B.

Two waves are simultaneously passing through a string and their equations are :

y_1=\mathrm{A_1}\sin k(x-vt)

y_2=\mathrm{A_2}\sin k(x-vt+x_0)

. Given amplitudes

\mathrm{A_1}=12

mm and

\mathrm{A_2}=5

mm,

x_0=3.5

cm and wave number

k=6.28\ \mathrm{cm^{-1}}

. The amplitude of resulting wave will be __________ mm.

Official answer

NTA final key.

Chapter: Waves
Topic: Waves on Strings
Idea tested: Superposition of Traveling Waves

Same idea in other shifts

Asked 3× in all

8 Apr 2025, Shift 2 · Q40The amplitude and phase of a wave that is formed by the superposition of two harmonic travelling waves, $y_1(x, t) = 4\sin(kx - \omega t)$ …MediumSingle correct
9 Jan 2020, Shift 1 · Q9Three harmonic waves having equal frequency $\nu$ and same intensity $I_0$ , have phase angles $0, \frac{\pi}{4}$ and $-\frac{\pi}{4}$ …MediumSingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.