Basic Special Relativity Question

Discussion in 'Physics & Math' started by Fednis48, Apr 22, 2013.

  1. Pete It's not rocket surgery Moderator

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    Sorry, Tach, but I don't know what you're thinking. I'll take a break until you spell it out.
     
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  3. Tach Banned Banned

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    You are very entertaining, I must give it to you. I hope you'll understand why I have difficulty taking anything you say seriously.
     
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  5. Tach Banned Banned

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    Using your own expressions, calculate \(y^"_B-y^"_A\).

    In \(S''\):
    \(\begin{align} A'' &= \left(x_A''(t''), \ y_A''(t'') \right)\\ &= \left(-Vt'', \ -u\gamma'(t'' + \frac{Vx_A''}{c^2}) \right ) \end{align}\)
    \(\begin{align} B'' &= \left(x_B''(t''), \ y_B''(t'') \right) \\ &= \left(\frac{1}{\gamma'} - Vt'', \ -u\gamma'(t'' + \frac{Vx_B''}{c^2}) \right) \end{align}\)​
     
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  7. Fednis48 Registered Senior Member

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    Ok, I'll bite.

    \(y_B''(t'')-y_A''(t'')=-u\gamma'(t'' + \frac{Vx_B''}{c^2})+u\gamma'(t'' + \frac{Vx_A''}{c^2})=\frac{Vu\gamma'}{c^2}(x_A''-x_B'')\)

    Agree so far? I'd keep going and plug in the expressions for x, but I'm afraid that if I try to do more than one step at a time, you'll just shut down and go back to mocking me for vaguely wrong algebra.
     
  8. Tach Banned Banned

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    You are getting close(r) but you still have a laughable mistake.
     
  9. Pete It's not rocket surgery Moderator

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    Yes, I've done that, you can see the result in the opening post.
    What do you get?
     
  10. Tach Banned Banned

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  11. Pete It's not rocket surgery Moderator

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    Perhaps if you explained what you are thinking, we might make progress?
     
  12. Fednis48 Registered Senior Member

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    Name one.
     
  13. Tach Banned Banned

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    You are missing part of the expression.

    I hope you would understand why I can't take your posts seriously.
     
  14. Fednis48 Registered Senior Member

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    Oh, sorry! When I posted that, I realized I'd made a typo and immediately edited it. It looks like you got around to responding in the ~10 seconds before I'd made the correction. It should be right now.
     
  15. Motor Daddy ☼☼☼☼☼☼☼☼☼☼☼ Valued Senior Member

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    When you're done goofing around give me the times in the train frame. Give me the acceleration of the rod in the train frame. Give me the duration of travel of the rod. I'm gonna run circles around you, Tach, and I have to say, I'm gonna enjoy it.

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  16. Tach Banned Banned

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    Nah, it was a lot longer than that, I made three posts giving you hints as to the error.
    Now, can you explain to Pete his (and your) error?
     
  17. Tach Banned Banned

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    LOL. Keep dreaming.
     
  18. Pete It's not rocket surgery Moderator

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    I still don't know what you're thinking, Tach.
    Please stop hinting and spell it out.
     
  19. Tach Banned Banned

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    I'll let your buddy explain it to you, I don't think that you'll accept the correction from me. The fact that you STILL can't (or won't) see the error speaks volumes about how you think.
     
  20. Pete It's not rocket surgery Moderator

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    I'm beginning to suspect that there's no error there at all.
    If there is, why don't you prove it?
     
  21. Tach Banned Banned

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    I already did. Hours ago. Shakes head in disbelief.
     
  22. Pete It's not rocket surgery Moderator

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    That's not a proof, Tach, that's an unsupported assertion.
    Please show how you got that result.
     
  23. Fednis48 Registered Senior Member

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    NO I CAN'T YOU ELITIST TWIT. Your "hints" have been that something is missing from my answer, and that my mistake is laughable. If you call those hints, I pity anyone who actually tries to learn something from you. At the beginning, demanding that we find the error ourselves might have been pedagogical. It's long since crossed the line into just sadistic, even if there is an error to be found, which I'm convinced there's not. Specify a mistake or naff off.
     

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