Re: A famous "paradox" of relativity : Plzz Help solve


"The Ghost In The Machine" <ewill@xxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:apmda5-2sb.ln1@xxxxxxxxxxxxxxxxxxxxxxxxxx
| In sci.physics, Varun
| <sithlordvarun@xxxxxxxxx>
| wrote
| on Sun, 9 Mar 2008 10:02:00 -0700 (PDT)
| <ee22827e-a309-4067-a6e5-cd56b8fd300b@xxxxxxxxxxxxxxxxxxxxxxxxxxx>:
| > A famous "paradox" of relativity is the following: A high-speed runner
| > carries a 10-foot-long pole toward a barn that is 10 feet long and has
| > doors open at both ends. The runner is going so fast that, from the
| > point of view of the farmer who owns the barn, the pole is only 5 feet
| > long. Clearly, the farmer can close both barn doors and trap the
| > runner in the barn. But to the runner, the pole is 10 feet long and
| > the barn, rushing toward the runner, is only 5 feet long. So clearly
| > the runner can't be in the barn with both doors closed. Can you
| > resolve the paradox, using the fact that events simultaneous in one
| > reference frame aren't simultaneous in another? (By the way, the speed
| > required here is 0.866c.)
|
| There's no problem here. The door events are at (0,t),
| (10,t) in door space, and the pole events are at (0, t1),
| (x,t2) in pole space for some values of t, x, t1, and t2.
| It turns out the pole events transform into (0,t) and
| (10/g, t), where g = 1/sqrt(1-v^2/c^2), in door space.
| This means the pole will fit nicely through the door.
|
| If one wants to evaluate the entire problem in pole space,
| remember that the door must also rotate.
|
There IS a problem here. See a psychiatrist, you are a lunatic.
BTW... most barn doors rotate, that's what the hinges are for.





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