The doppler effect and red shift

HideShow resource information
View mindmap
  • The Doppler effect
    • Red shift
      • To change the colour of an object, you change the wavelength of the light that's coming from it
      • Happens with stars and galaxies
        • Stars are often moving away from us and away from each other
      • When a star is moving away, the light waves coming off it become more stretched out
        • Shifting the rays to the red part of the spectrum
        • Making it seem more red
      • If an star were to move towards you, the light waves would become more squashed
        • Shifting it to the blue part of the spectrum
        • Making it appear to be blue
      • Used as evidence for the theory of how the earth began
        • More distant galaxies have greater red-shifts than nearer ones
          • More distant galaxies are moving away from us faster than nearer ones
            • Provides evidence that the whole universe is expanding
      • Light waves
    • Sound waves are longitudinal
    • When a car is moving towards you, the waves in front of it compress
      • Get "squashed" together
      • This makes the wavelength get shorter
        • So the frequency gets higher
          • So the pitch goes up
    • If a car is moving away then the sound waves spread out
      • Making the wavelength seem longer
        • So the frequency gets lower
          • So the pitch goes down
    • Both light and sound waves

Comments

No comments have yet been made

Similar Physics resources:

See all Physics resources »See all Waves resources »