JEE Main 2013PhysicsWaves and SoundHardMCQ

JEE Main 2013 — Waves and Sound Question with Solution

JEE Main 2013 (07 Apr)

Question

A sonometer wire of length 1.5m is made of steel. The tension in it produces an elastic strain of 1% . What is the fundamental frequency of steel if density and elasticity of steel are 7.7×103 kg m-3 and 2.2×1011 N m-2 respectively?

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Show full solutionCorrect option: D
Correct answer
D178.2 Hz

Step-by-step explanation

f = V 2 ℓ = 1 2 ℓ T μ = 1 2 ℓ T Ad

Also, Y = T ℓ A Δ ℓ       ⇒   T A = Y Δ ℓ ℓ       ⇒   f = 1 2 ℓ Y Δ ℓ ℓ d

ℓ = 1.5 m,  Δ ℓ ℓ = 0.01, d = 7.7 × 1 0 3  kg / m 3

Y = 2.2 × 1 0 1 1  N / m 2

After solving

f = 2 7 × 1 0 3 3 Hz

f  ≈  178.2  Hz

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About this question

This is a previous-year question from JEE Main 2013, 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.