Question

 

Two sounding bodies producing progressive waves given by 

                                     

are situated very near to the ears of a person who will hear

Solution

Correct option is

2 beats per second with intensity ratio 49/1between maxima and minima.

 

The two amplitude of the two sounds are a1 = 4 units and a2 = 3 units. Their angular frequencies are ω1 = 400 π rad s–1 and ω2 = 404 π rad s–1. Therefore, their frequencies are V1 = 200 Hz and V2 = 202 Hz. Hence the beat frequency = V2 – V1 = 2 Hz, i.e. the person will hear 2 beats per second. The intensity ratio is given by

                           

SIMILAR QUESTIONS

Q1

 

A wave is represented by the equation  

                                  

Where x is in metres and t in seconds. The expression represents

Q2

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Q3

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Q4

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Q5

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Q6

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Q7

A tuning fork of frequency 480 Hz produces 10 beats per second when sounded with a vibrating sonometer string. What must have been the frequency of the string if a slight increase in the tension of the string produces fewer beats per second than before?

Q8

A train blowing its whistle moves with a constant velocity u away from the observer on the ground. The ratio of the actual frequency of the whistle to that measured by the observer is found to be 1.2. If the train is at rest and the observer moves away from it at the same velocity, the ratio would be given by

Q9

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Q10

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