A source of sound emits waves with frequency f Hz and speed V m/sec. Two observers move away from this source in opposite directions each with a speed 0.2 V relative to the source. The ratio of frequencies heard by the two observers will be

  • Option 1)

    3:2

  • Option 2)

    2:3

  • Option 3)

    1:1

  • Option 4)

    1:5

 

Answers (1)
P Plabita

As we learnt in 

Doppler Effect -

When a source of sound and a listener are in motion relative to each other, the frequency of the sound heard by the listener is not the same as the source frequency.

-

 

The direction of motion of observer does not effect frequency heard by them. Since both are moving away from source, frequency heard by them is same.

\therefore Ratio=1

 


Option 1)

3:2

This option is incorrect.

Option 2)

2:3

This option is incorrect.

Option 3)

1:1

This option is correct.

Option 4)

1:5

This option is incorrect.

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