JEE Main 2016PhysicsWaves and SoundMediumMCQ

JEE Main 2016 — Waves and Sound Question with Solution

JEE Main 2016 (10 Apr Online)

Question

A toy-car, blowing its horn, is moving with a steady speed of 5 m s-1, away from a wall. An observer, towards whom the toy car is moving, is able to hear 5 beats per second. If the velocity of sound in air is 340 m s-1 the frequency of the horn of the toy car is close to

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Show full solutionCorrect option: D
Correct answer
D170 Hz

Step-by-step explanation

Frequency heard by the observer directly from source f340340-5=f1

Frequency heard by the observer coming after relection from wall 
f340340+5 = f 2

Beats frequency=f1-f2

5=f340340-5-340340+5

⇒ f=170 Hz

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About this question

This is a previous-year question from JEE Main 2016, 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.