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

 

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

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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