The Doppler Effect: Near and Far Galaxies

AI Thread Summary
The discussion centers on understanding how the Doppler Effect differentiates between nearby and distant galaxies. It highlights that the redshift of light from receding galaxies increases with distance, indicating that more distant galaxies are moving away faster due to the expansion of the universe. The concept of Hubble's Law is mentioned, which relates the redshift to the velocity and distance of galaxies. The user seeks clarification on how redshift measurements can be used to determine distances to galaxies. Overall, the conversation emphasizes the relationship between redshift, velocity, and distance in the context of cosmic expansion.
jerome951000
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I found a question in a Maltese physics past paper dealing with the doppler effect. I managed to figure out the part dealing with the effect of motion of the wave source, but i was asked this:

How does The Doppler Effect show us the difference between galaxies that are near and those that are far away?

I was familiar with the doppler effect and the motion of the source causing it, but i never knew that the distance could make a difference. Any help would be much appreciated.
 
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Try a Google search on "Hubble expansion".
 
thanks that was really helpful. it said that the redshift acquired value of the velocity of the receding galaxies is proportional to their distance from earth. thanks again :-)
 
how are the distances between the Earth and other galaxies deciphered using the redshift acquired velocity since these two are proportional?
 
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