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

Got wrong from right equations

  1. Dec 4, 2006 #1
    I got this problem while I was combining relativistic equations:



    For particle which is in motion,
    v = l /t
    or, l = v * t
    or, l= v * t0/(1-v^2/c^2)^(1/2) ' Relativistic equation for time "t"

    If the particle was light,

    l =(c * t0)/(1-v^2/c^2)^(1/2) ' Because velocity of light is always c; c*t0 is equal to l0

    or l = l0 / (1-v^2/c^2)^(1/2)

    But, the actual relation is l = l0 * (1-v^2/c^2)^(1/2)

    I must have been wrong somewhere. Where?
     
  2. jcsd
  3. Dec 5, 2006 #2

    dextercioby

    User Avatar
    Science Advisor
    Homework Helper

    You should have been consistent when plugging v--->c in your equations.

    Daniel.
     
  4. Dec 5, 2006 #3
    use lorentz-einstein transformation

    Your light signal that starts at t=0 from x=0 generates the event after a time t of propagation (x=ct;t=x/c) in I. The same event detected from I' is (x'=ct';t'=x'/c) and so
    l=(x-Vt)/(1-bb)^1/2=l'((1+b)/(1-b))
    with b=V/c.
    the best things a physicist can offer to another one are information and constructive criticism
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Got wrong from right equations
Loading...