Hubble's Law Flashcards
What do wavefronts do?
Join equal points on a wave
What is the Doppler effect?
The apparent change in the frequency of a wave caused by relative motion between the source of the wave and the observer.
What happens to the pitch when the sound is approaching the observer?
The smaller wavelength causes a higher frequency, meaning higher pitch
What happens to the pitch when the sound is receding from the observer?
The longer wavelength causes a lower frequency, meaning lower pitch
How does the Doppler effect relate to the star spectrum?
Light from a star is shifted higher or lower in frequency if the source is moving further or closer to us
How can an absorption spectra be used to tell if the stars are moving?
The spectral lines give the star’s elemental composition. If this is shifted, the star is moving towards/away from us.
The greater the shift, the ____ the speed.
Greater
What is a blue shift?
Spectrum moving towards us
What is a red shift?
Spectrum moving away from us
Further away the galaxy is, the ____ it is receding
faster
Universe began at a:
single infinitely dense point
The universe is thought to be started by the:
Big Bang Theory
What does Mly stand for?
mega light year
What is the relationship between the distance a galaxy is from Earth and its receding velocity?
Direct proportion
What is Hubble’s Law?
V=H(constant)*D
