JEE Main 2019PhysicsWaves and SoundEasyMCQ

JEE Main 2019Waves and Sound Question with Solution

JEE Main 2019 (09 Apr Shift 1)

Question

A string is clamped at both the ends and it is vibrating in its 4th harmonic. The equation of the stationary wave is y=0.3sin0.157x cos(200πt). The length of the string is
(All quantities are in SI units.)

Choose an option

Show full solutionCorrect option: D
Correct answer
D80 m

Step-by-step explanation

From the equation, k=0.157
2πλ=0.157
λ=40 m
But, length of the wire in 4th harmonic, l=4×λ2=2λ=80 m.

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About this question

This is a previous-year question from JEE Main 2019, covering the Waves and Sound chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.