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Light Perception

  1. Mar 16, 2004 #1
    Now, I got this from a very reliable source, an encyclopedia to be precise, so I know it's correct and goes according to the Einstein velocity addition formula. My question is, why?

    Question 1: Is it because a person can never "perceive" something coming at them faster than the speed of light?

    Question 2: Assuming there are people in these theoretical ships, looking at eachother, and the ships are traveling directly at eachother...Would the two ships crash before a person in one of the ships 'sees' the other ship hitting it (say, 1 cm away)?

    Sorry if these questions are unclear, I don't have a big vocabulary of physics terms.
  2. jcsd
  3. Mar 16, 2004 #2

    Doc Al

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    Staff: Mentor

    It's not a trick of perception, if that's what you mean. According to relativity, the speed of a massive object as measured in an inertial frame cannot equal (or exceed) the speed of light.
    Why? Since the light from the approaching ship travels faster than the ship itself, it will reach the other ship before the crash.
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