🚀 go-pugleaf

Androcles <Headmaster@Hogwarts.physics> wrote in message
  tfzYl.1856$FO5.1728@newsfe08.ams2
> "Gordon Stangler" <gordon.stangler@gmail.com> wrote in message
> news:3b0f30a7-88c3-4376-8338-fe9f2352980c@g15g2000pra.googlegroups.com...
>> Pentcho,
>> 
>> In one frame, the pole is length contracted to fit inside the barn,
>> and the barn doors are closed simultaneously, trapping the pole
>> inside.  The doors are then opened, allowing the pole to pass through.
>> 
>> In the other frame, the barn is length dilated, but the barn doors are
>> closed, first one, then the other, and opened one after another,
>> <different times>.  We have to drop simultaneity in order to get the
>> pole through the barn.
>> Hope this helps.
> 
> 
> Suppose the length of the barn is 10m, and the length of the
> pole is also 10m when at rest in the barn.
> Being a barn, it is closed at one end and the door is closed
> as the pole enters. It will fit when at rest.
> 
> Calculate the length of the pole when moving at 0.866c.
> 
> xi = (x-vt)/sqrt( 1-v^2/c^2)
>  http://www.androcles01.pwp.blueyonder.co.uk/Smart/x'=x-vt.gif
> 
> xi = (10m)/sqrt (1-0.866^2/1^2)
> = (10m)/sqrt (1-0.75)
> = (10m)/sqrt (0.25)
> = (10m)/0.5
>   = 20m
> It will not fit until it is brought to a sudden stop.
> 
> Your idiot drool doesn't help at all, you are a fuckwit.
> Why do you incompetent fuckin' lunatics call it length
> "contraction"?

No, imbecile, you don't understand the meaning of the variables.

If you use the equation
     xi = (x-vt)/sqrt( 1-v^2/c^2),
you have two events:
Event_1:
    (x1,t1) = (0,0)
    (xi1,tau1) = (0,0)
Event_2:
    (x2,t2) = (x,t)
    (xi2,tau2) = (xi,tau)

When you calculate
     xi = (x-vt)/sqrt( 1-v^2/c^2)
with
    x = 10
and
    t = 0,
you measure the endpoints x1 and x2 simultaneously in the rod's rest
frame, so you have xi1 and xi2 at DIFFERENT times
    tau1 = 0
and
    tau2 = tau.

Do you also measure the length of a moving train by subtracting the
measured distances to the front and the rear at different times?

Are you some kind of retired engineer or something?
What a dope :-)

Dirk Vdm