GCSE physics

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GCSE physics
2012-04-29 03:51:26
use waves communication provide evidence that universe expanding

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  1. why tye of radiation has the longest wavelngth
  2. which type of radiation has the highest frequency
    visible light
  3. which has the shortest wavelength
  4. the universe seems to be
    expanding , all its galaxies seem to be moving further away from each other
  5. light from other galaxies
    has been shifted to the red end of the spectrum because the wavelength has increased
  6. measurements of the red shift suggest that all the galaxies are moving ....... from us very quickly
  7. more distant galaxies have ..... red shifts than nearer ones . this means that more distant galaxies are moving .... from us ...... than the nearer ones . this provides evidence that the whole universe is expanding
    • greater
    • away
    • faster
  8. when something that emits waves moves towards you or away from you the wavelengths and frequencies of the waves seem different - compared to when the source of the wave is stationary the frequency of a source moving towards you will seem ...... and its wavelenght will seem ........ . the frequency of a source moving away from you will seem ...... and its wavelenght will seem .......
    • higher
    • shorter
    • lower
    • longer
  9. what does the big bang theory state
    right now distant galaxies are mocing further away from us - the further away a galaxy is away from us the faster they're moving away . But something must have got them going . that something was probably a big explosion - so they called it the big bang theory . According to this theory all the matter and energy in the universe must have been compressed into a very small space . Then it exploded from that single point and started expanding
  10. scientists have detected low electromagnetic radiation coming from all parts of the universe . this radiation :
    is largely in the microwave part of the EM spectrum . Its known as the cosmic microwave background radiation (CMBR)
  11. the big band theory is the only theroy that can explain the CMBR . Just after the big bang while the universe was still extremely hot , everything in the universe emitted very high frequency radiation as the universe expanded
    it has cooled , and the radiation has dropped in frequency and is now seen as microwave radiation
  12. a summary of the big bang and its interpretation
    1 = the light from other glaaxies has been red shifted
    2 = the further away the galaxy , the more its light has been red shifted
    3 = CMBR
    • intepretation
    • 1 = the other galaxies are moving further away from us
    • 2 = the most likley explaination is that the universe is expanding . this suppots the theory that the start of the universe could have been from a single explosion
    • 3 = the relatively uniform background radiation is the remains of energy created just after the big bang
  13. a student listens to the sound waves produced by a car siren . when the car is stationary , the student hears a constant frequency sound . describe how the wavelength and frequency of the sound waves heard by the student change when the car moves away from the student
    the frequency is lower and the wavlength is longer
  14. what is red shift
    it is when light has been shifted to the red end of the spectrum because the wavelength increases , this is an indication that the glaaxies are moving further apart
  15. describe the big band theory
    all matter comes from a single point , a massive explosion sent matter outwards , so the universe is expanding
  16. suggest what scientist should do if new evidence were found that did not support the big bang theory
    either check the reliability of the evide or change the thoery to match the new evidence