JEE Main 2021 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 26 August 2021, Shift 1, Physics Q24

Question 24 of 90 in this shift, Physics question 24 of 30, Section B.

Two travelling waves produces a standing wave represented by equation.

y=1.0\ \mathrm{mm}\ \cos(1.57\ \mathrm{cm^{-1}})\ x\ \sin(78.5\ \mathrm{s^{-1}})t

. The node closest to the origin in the region

x>0

will be at

x=

__________ cm.

Official answer

NTA final key.

Chapter: Waves
Topic: Waves on Strings
Idea tested: Nodes and Antinodes

Same topic in other shifts

All Waves on Strings questions

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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.