Doppler effect (the sound source moving towards observer)

Therefore, when the sound source is moving towards the observer, the speed of sound relative to the observer remains the same. This is because the frequency of the sound wave does not change, but the wavelength does. As the wavelength becomes shorter, the speed of sound relative to the observer is reduced. This is due to the equation v = f x (lambda), where v is the speed of sound, f is the frequency, and (lambda) is the wavelength. Thus, the speed of sound relative to the observer is not affected by the movement of the sound source.
  • #1
desmond iking
284
2

Homework Statement



the observer is stationary , but the sound source is moving towards the observer , i was told that the speed of sound relative to the observer doesn't change. why is it so ? in my opinion, the speed of sound relative to observer changed . because of v= f x (lambda) , as the frequency of sound is fixed , but the wavelength of sound waves now changed , (the wavelength now become shorter) , so the speed of sound realtive to the obersver is reduced . am i correct ?

Homework Equations





The Attempt at a Solution

 
Physics news on Phys.org
  • #2
The speed of sound in a medium is a property of the medium, not the source or the observer.
 

What is the Doppler effect?

The Doppler effect is a phenomenon where the perceived frequency of sound waves changes when the source of the sound is moving relative to the observer. This results in a perceived change in pitch as the sound source moves closer or farther away from the observer.

How does the Doppler effect work?

The Doppler effect is caused by a change in the frequency of the sound waves as the source moves. When the sound source moves towards the observer, the waves get compressed, resulting in a higher perceived frequency or pitch. Conversely, when the sound source moves away from the observer, the waves get stretched, resulting in a lower perceived frequency or pitch.

What factors affect the magnitude of the Doppler effect?

The magnitude of the Doppler effect is affected by the speed of the sound source, the speed of the observer, and the frequency of the sound waves. Generally, the faster the sound source is moving, the greater the change in frequency will be. The speed of the sound waves also plays a role, as higher frequency waves are more affected by the Doppler effect than lower frequency waves.

Does the Doppler effect only occur with sound waves?

No, the Doppler effect can also occur with other types of waves, such as light waves. This is known as the "red shift" and "blue shift" in astronomy, where the perceived color of an object changes depending on whether it is moving towards or away from the observer.

How is the Doppler effect used in real life?

The Doppler effect has many practical applications, such as in radar and sonar systems, where the change in frequency of the reflected waves can be used to detect the speed and direction of moving objects. It is also used in medical imaging techniques, such as ultrasound, to measure blood flow and heart rate.

Similar threads

  • Introductory Physics Homework Help
Replies
1
Views
3K
  • Introductory Physics Homework Help
Replies
7
Views
1K
Replies
3
Views
631
  • Introductory Physics Homework Help
Replies
7
Views
2K
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
905
  • Introductory Physics Homework Help
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
1K
Back
Top