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Homework Help: Need help with problem

  1. Sep 27, 2004 #1

    nyu

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    This isn't homework, but I missed the last few classes so I'm in dire need of help. I was given a quiz today, amazingly - I was able to do all of it with just basic math knowledge....except one >_> And it's bothering me that I don't understand it >_>

    Here is the problem:

    [img width=111 height=96][PLAIN]http://www.fall3n.com/homewo...horoughly, it'd be appreciated ;) Thank you!
     
    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Sep 27, 2004 #2

    Tide

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    Science Advisor
    Homework Helper

    I assume that's a radical in the denominator.

    Multiply both sides by the radical, square both sides then solve for v.
     
  4. Sep 27, 2004 #3
    Ok um I am assuming the equation is [tex] t=T/(1-(V^2/c^2)) [/tex]

    therefore

    t = T*v^2
    -------
    v^2-c^2
    therefore
    v=-c sqroot(t)
    -----------
    sqroot(t-T)
     
  5. Sep 27, 2004 #4
    Alright I kind of cheated and used the calculator last time
    but I solved by hand and got the following

    [tex]t=\frac{T}{{1 - v^2/c^2}}[/tex]

    [tex]t=\frac{Tc^2}{{c^2-v^2}}[/tex]
    [tex]c^2-v^2=\frac{Tc^2}{{t}}[/tex]
    [tex]-v^2=\frac{Tc^2}{{t}}-c^2[/tex]
    [tex]v^2=\frac{-Tc^2}{{t}}+\frac{c^2t}{{t}}[/tex]
    [tex]v^2=\frac{tc^2-Tc^2}{{t}}[/tex]
    [tex]v^2=\frac{c^2(t-T)}{{t}}[/tex]
    [tex]v=+ or - \frac{c\sqrt{(t-T)}}{{t}}[/tex]
     
  6. Sep 27, 2004 #5
    I am very tired though and could have made a mistake please check your answers with someone else or have someone confirm mine
     
  7. Sep 28, 2004 #6

    HallsofIvy

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    Science Advisor

    Yes, Tom McCurdy's last response:

    [tex]v=+ or - \frac{c\sqrt{(t-T)}}{{t}}[/tex]

    is correct.
     
  8. Sep 28, 2004 #7
    YES... not only did i do some algerbra but I learned latex
     
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