science test #5

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  1. define cosmolgy or astronomy
    the study of the universe
  2. what dose human experience refer to in the universe
    it includes all known matter,energy,time, and space
  3. what % of the universe is believed to be space
  4. how do we measure space
    a light year
  5. define light year and its speeds
    is the distaces light travels at a speed of (186,000 miles/sec or 300,000 km/sec) in one year
  6. how many miles is a light year
    5.8 trillion miles
  7. define doppler effect
    refers to the change in radiation emitted from an object as it moves( towards or away)
  8. what color and length will light be if it is moveing towards you
    blue and short
  9. what color and length will light be if it is moveing away
    red and long
  10. if light has sound and is moveing towards you what sound and length will it be
    short and have a very high pitch
  11. if light has sound and it is moveing away what sound and lenght will it be
    long and a very low pitch
  12. define hubbles law and what year it was
    1929- states that the galaxies are recedine at a rate that is proportional to their distance
  13. if a star or galaxy is faint or dim what can you say about it
    faraway,fast,large,red shift
  14. if a star or galaxy is bright what can you say about it
    close,slow,small,red shift
  15. define background radiation
    is a form of energy associated w/ blasts or explosions and is observed at the outermost limits of the universe
  16. define big bang theory
    a concept that our universe originated from an immensly hot dense source that is the site of a cataclysmic explosion 14-15b billion years ago
  17. define open universe
    expand forever
  18. define big crunch
    galaxy wouls stop and collaspe in on itself
  19. define critical density
    1 atom per cubic meter to make big crunch
  20. do we have enough critical density to make big crunch
  21. our known theory of the universe is it big crunch or open universe
    open universe
  22. define dark matter
    is a form of matter that dose not emit or reflect any know form of radiation
  23. dark matter is part of what theory
    big crunch
  24. E=mc2
    • Energy
    • Mass
    • C= Speed of light
  25. define a nebula
    concentrations of interstellur matter (there are 3)
  26. what is a dark nebula
    • interstellur=IN
    • IN matter- very dense clouds of hydrogen gas and dust located far from a source of light postioned between earth and a bright region of space
  27. what is a reflection nebula
    IN matter very dense clouds of hydrogen gas and dust having a significate source of light will bend this light back and appear as a source of light
  28. what is an emmission nebula
    IN matter low density hydrogen gas under low pressure will absorb UV radiaition and transmitte the radiation as visible light
  29. what is the process fo taking raditation you cant see and transmitting it as visible light
  30. define incandescence
    a substance is heated to the point it becomes hot enough to radiate visible light
  31. define galaxy
    contraction of stars (billions)
  32. how is a galaxy named and why
    by symmerty-shape
  33. define irregular galaxy
    mostly hygrogen gas w/ a significate amount of young stars having little or no symmerty (rarest)
  34. defien elliptical galaxy
    most abandant -mostly old mature stars with little hydrogen gas- having a spherical to oval shape
  35. milky way is what type of galaxy
  36. define barred spiral galaxy
    Image Uploadstars in arm rotate faster than the stars in the core giving a rigid solid shape a bar shape
  37. define spiral galaxy
    Image Uploada centeral core made up of relativly mature stars -arms are made up of relativly young stars and hydrogen gas extends from the core. stars in the arm rotate slower than the stars in the core giving it a pinnwheel shape
  38. is the milky way one of the biggest galaxies having billions of stars
  39. Image Uploadhow many light years is the milky way galaxy from one end to the other and at its core (on its side)
    • 100,000 light years
    • 10,000 at the core
  40. milky way has how many major arms
  41. where are we located
    2/3 from the core out in an arm
  42. what is H-R star diagram
    Image Uploadit plots star brightness blue being high- yellow being middle-red being low
  43. what can you say about a blue star
    bright has high or hot temps
  44. what can you say about a yellow star
    it has an average temp and brightness
  45. what can you say about a red star
    it is dim and has low or cool temps
  46. whats % of a stars life is spent in main sequence(being in the middle)
  47. define luminosity and magnatude
    refers to the brightness of a star
  48. if you plot a star for its temps and brightness what are they found mostly to be
    main sequence stars
  49. what is the lifespan of a red-cool star
    100's of billions of years
  50. what is the lifespan of a blue-hot star
    few million years
  51. what is the lifespan of a yellow average temp star
    5-15 billion years
Card Set:
science test #5
2011-05-03 20:44:10

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