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

Will there be a collision?

  1. Sep 25, 2005 #1
    A very thin steel plate with a circular hole one meter in diameter centered on the y axis lies parallel to the xz plane in frame S and moves in the +y direction at constant speed v, a mterstick lying on the x axis moves in the x directoin with v/c.The steel plate arrives at the y=0 plane at the same instant teh center of the meterstick reaches the origin of S. Will there be a collision?
  2. jcsd
  3. Sep 25, 2005 #2


    User Avatar
    Science Advisor

    Not all that paradoxical. The steel plate (more specifically, the hole) moves in the y-direction so there is no relativistic change in the diameter of the hole. The meter stick is moving in the x direction so there is contraction. By the way, (although it doesn't affect the answer) are you sure about that "with v/c"? Was that "with speed v/c"? In that case, what are the units?
  4. Sep 25, 2005 #3
    yeah, but if you see it in the meter stick' coordinate, then the steel plate does have a relativisic change: it moves in the x direction
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook