Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Vectors and the Speed of Light?

  1. Jun 4, 2009 #1
    Can the speed of light be broken using vectors? Why not? Where does the Lorentz Transformation come into play?

    E.g. I accelerate to 3/4 the speed of light North and then to 3/4 the speed of light East. Am I traveling faster than the speed of light at 45 degrees North-East?
  2. jcsd
  3. Jun 5, 2009 #2


    User Avatar
    Science Advisor
    Gold Member

    If you travel 1 m/s for 1 hour to the north and the 1 m/s for 1 hour to the east, how fast did you travel? 1 m/s or 1.414 m/s?
  4. Jun 5, 2009 #3


    User Avatar

    Staff: Mentor


    The usual relativistic "velocity addition" formula applies only when the velocities are along the same line.

    For adding velocities that are at an angle with each other, see for example the section The velocity addition formula for non-parallel velocities on this page.
  5. Jun 6, 2009 #4
    the speed of light is fixed for all obsevers. for all frames of reference.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook