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What The?

  1. May 29, 2008 #1
    What The??

    Ok so i came across this relativity problem in my textbook (Physics by Cutnell & Johnson) and i have absolutely no idea what to do:uhh: Help please...

    An intergalactic cruiser has two types of guns: a Photon cannon that fires a beam of laser light and a ion gun that shoots ions at a velocity of 0.950c relative to the cruiser. The cruiser closes in on an alien spacecraft at a velocity of 9.800c relative to this spacecraft. The captain fires both types of guns. At what velocity do the aliens see (a) the laser light and (b) the ions approach them? At what velocity do the aliens see (c) the laser light and (d) the ions move away from the cruiser.

    Eish :biggrin: if i can just get what equations to use..that would also help
    Last edited: May 29, 2008
  2. jcsd
  3. May 29, 2008 #2
    seems to me you have missed some few articles convincing us that such a speed is possible.

    but if you ment 0.98c than its easy

    you have to read a little about Lorentz transformations and the equasion to use is also there see en.wikipedia.org/wiki/Lorentz_transformation
  4. May 29, 2008 #3
    Ah thanks...found it. You're right it is actually easy, whoops
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