What is meant by the doppler effect?

The doppler effect is the change in frequency and wavelength of waves coming from a wave source moving relative to you. If a wavesource is stationary then the waves in all directions all have the same frequency and wavelength, with the waves forming concentric (surrounding) circles around the wave source. If a wave source is moving, however, the waves located in the direction it is moving will be compressed, leading to them having a shorter wavelength and a higher frequency. On the other side of the wave source, the opposite occurs. You may have heard this effect from an ambulance, as the pitch of it's siren rises when its frequency increases (when it approaches you) and lowers when it moves away. The same principle can be used to determine the velocity of distant stars.

TD
Answered by Thomas D. Physics tutor

1797 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

A ball is hit horizontally at a height of 1.2 m and travels a horizontal distance of 5.0 m before reaching the ground. The ball is at rest when hit. Calculate the initial horizontal velocity given to the ball when it was hit.


Can you talk me through how to solve problems on projectiles? I always get confused


Find current and voltage across resistors R1 and R2, when they connected in parallel and in series. A 12V battery is connected, R1=4Ω and R2=3Ω.


Describe and explain the vertical motion of a parachutist which jumps out of an aeroplane at time t=0 and then releases the parachute shortly after reaching terminal velocity at time t=T. (Assume air resistance is not negligible).


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences