﻿   The frequency of the sound of a car horn as received by an observer towards whom the car is moving differs from the frequency of the horn by 2.5%. If the speed of sound in air is 320 ms–1, the speed of the car is : Kaysons Education

# The Frequency Of The Sound Of A Car Horn As Received By An Observer Towards Whom The Car Is Moving Differs From The Frequency Of The Horn By 2.5%. If The Speed Of Sound In Air Is 320 Ms–1, The Speed Of The Car Is

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## Question

### Solution

Correct option is

7.8 ms–1

Here, we have

…(i)

Using this in (i) we have

Which gives us â‰ƒ 7.8 ms–1.

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