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Concept question

  1. Nov 12, 2003 #1
    i'm jux wondering would a laser mounted on a spaceship travelling at half the speed of light... wouldn't this make the speed of the laser on the ship change to 1.5c??

  2. jcsd
  3. Nov 12, 2003 #2


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    No. The speed of light is always locally measured to be c. This is the first postulate of special relativity.

    - Warren
  4. Nov 12, 2003 #3


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    People who see the spaceship moving at 0.5 times the speed of light would see the laser at a different (blue shifted) color that the people on the spaceship.
  5. Nov 12, 2003 #4
    but the observer still see the speed of the laser to be c.?
    so the speed the stay the same, only the wavelength change according to the observer perspective??
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