Doppler Effect Flashcards
1
Q
What is Doppler effect caused by?
A
the relative motion of an observer and a wave source. Causes frequency and wavelength to change
2
Q
What does red shift tell us?
A
Wavelength has stretched. Object is moving away . Universe is expanding.
3
Q
What does blue shift tell us?
A
Wavelength has been squashed. Moving towards us.
4
Q
Hubble’s Law
A
There is a direct correlation between the distance to a galaxy and it’s recessional velocity ( speed it is moving away)
5
Q
Recessional velocity
A
rate at which an astronomical object moves away
6
Q
Why has Hubble’s constant changed over time?
A
Technology advances ( more powerful microscopes). Distance of galaxies has become more accurate
