: It's because when the ambulence is moving towards you the sound waves get compressed, and what happens is many sound waves entered your ears at the same time, so the pitch is high. When the ambulence moves away, you will hear low pitch, because the waves are getting expanded, and you only get a few sound waves entering your ears in a sec.

<== Watch this video, for visual understanding.

What is a pitch?

About:(A few things you need to know)

Red shift And Blue shift

14 comments

Comments (14)

Sreeshan

Dec 06, 2023

completed

Sreeshan

Dec 05, 2023

By evening i will complete all the questions

Uyir

Dec 05, 2023

Please see the questions

Uyir

Dec 04, 2023

Can doppler effect be observed in both longitudinal and transverse waves?
Why is doppler effect used in hospitals?
Doppler effect limitations?
Uses of doppler effect.
How does the doppler effect prove that the universe is expanding?

Sreeshan

Dec 06, 2023

Replying to

It is used to make image of your portion of body using ultrasound, it i used in military to detect speed of ships and submariens.

Sreeshan

Dec 06, 2023

Replying to

Limitation would be Doppler Effect is applicable only when the velocities of the source of the sound and the observer are much less than the velocity of sound. so if we have an aircraft travelling at supersonic, we can't use doppler effect to calcuulate it's speed, or even detect it.

Sreeshan

Dec 06, 2023

Replying to

Yes doppler effect can be observed in both longitudinal and transverse.

Tharun

Nov 30, 2023

As a kind remark, what does learning about doppler effect help me, apart from just expanding my knowledge

What is the applications of doppler effect in real life

I dont know, so it would be nice to know

Sreeshan

Dec 06, 2023

Replying to

Tharun, doppler effect is used in hospitals, known as Ultrasound medical imaging.

In this, there are hight frequency waves(over 20,000 hz) which is used in a part of your body, where the sound waves vibrate through that region of your body and makes a visual image how it looks inside that regoin, as it is much safer than x-ray.

also: Military services: SONARS, also known as Sound Navigation and Ranging system, helps detect the speed of ships and submarines through the help of Doppler's effect.

Tharun

Nov 30, 2023

I have a question.

Red shift is increase in wavelength, that means the wave whould be moving away from an object right? So for another, opposite object, the light must be moving towards it and so would it be blue shift? So is it all relative?

Sreeshan

Nov 30, 2023

Best Answer

Replying to

The star is already away from us, it is like the ambulance which just over took , the resulting waves after the ambulence passed will have a long wavelenght , so does the star, but the star is stationary and is emmiting light from where it is standing, but the waves will expand as it travels more distance.

Sreeshan

Nov 30, 2023

Like if you understood this article. 😀

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