Session Start Tue Mar 04 13:38:50
2003
Prabhu's Away
Message:
Suppose we have a 20 foot limo and
a 12 foot garage. Someone comes up with the idea of accelerating the limo to,
say, 75% the speed of light and driving into the garage. The idea is that,
according to Einsteinian relativity, the observer in the garage will see the
limo contract in length as a result of traveling at this high velocity, so that
it might fit into the garage, when we can then slam the door shut (or some such
similar procedure). There is a problem though. From the point of view of the
limo, the length of the garage is actually what's contracting. So while the
acceleration makes the stationary observer think the limo should fit, the moving
observer thinks it's even more impossible. Which one of them is right? What
happens? Does the limo fit inside the garage, or doesn't it?
�
It's a
shame physicists don't get to actually perform these insane thought experiments
they devise. I might consider becoming a physicist in that case.
K@ the answer
is that it won't fit. Or at least, it cannot fit in its current recognizable
state as a limo. At 75% the speed of light, the exterior, the frame and the rest
of the car will be melted or warped due to friction with air or otherwise
damaged.�
The driver would also die from all the G force
The answer is
always the 3rd option
Session Close�Tue Mar 04 13:41:20
2003
Session Start Tue Mar 04 13:41:33
2003
Prabhu:
lol
Prabhu: you can't take those
sorts of things into account!
K@�
and why not?
Prabhu: because it's
not the target of the question
K@� 
K@� the question just asked who was
right
K@� neither are
correct
Prabhu: fair
enough
K@�
.
.
.
Prabhu:
well in the first place it's kind of irrelevant, since no one knows how to
accelerate anything the size of a limo to anywhere near 75% the speed of
light
K@ the amount of energy
needed would be tremendous
Prabhu: no kidding
Prabhu: not to mention the g-forces would be
intolerable for any person, like you said
K@ yes
K@� that can be overcome if you install
autopilot
K@� but things would
melt�or as they compressed, things would have weird interactions and the
electronics may not communicate well
Prabhu:hmm that's true
K@� er, maybe not - since compression is
relative
K@� but the things that
are at the very edge of the car and interacting with the non-75% speed of light
air may be damaged
Prabhu: well
if you assume there is air, you would have to assume that there is a resulting
drag force, which means that as the car accelerates, it brings the air in front
of it up to the same speed
K@�
ok, what about the air to the side of the car?
Prabhu: hmm...I have no idea
Prabhu: I'm pretty sure the dynamics of air are
supercomplicated
K@� well, maybe
we can assume a limo and a garage in a vaccuum
Prabhu: yeah
Prabhu: that would probably be a meaningful
assumption
K@� lol - imagine a
limo in outerspace just hanging around
K@� but then you'd have to assume it was launched
to 75% speed of light without any of it's own combustion. Otherwise, it wouldn't
be a vaccuum anymore
K@� unless
you say that is neglible
Prabhu:
well exhaust would theoretically go entirely behind the car, so it wouldn't
interact with it as it continued to move forward
K@� well, exhaust goes behind - you are assuming
that the air will not travel fast enough to affect the rest of the
car?
K@� anyway, I still think it
must be launched. Otherwise, there would be serious tire melting�or wheels
flying off
Prabhu: heh
geez
K@� to get the car to move
by itself that fast
Prabhu: I
think this is a case where physicists "assume a spherical
chicken"
Prabhu: basically there
are tons of complexities
Prabhu:
but supposing we could ignore all of these, what would happen?
K@� lol - spherical chicken?
K@� would it lay a spherical egg?
Prabhu: haha good question
K@� I'd say that would be pretty
painful
Prabhu: I'm not sure how
the expression originated
Prabhu:
but it seems to be fairly common
K@�
.
.
.
K@� can
spherical chickens fly?
Prabhu:can normal chickens fly?
K@� some can
Prabhu: hmm ok
Prabhu: I'd have to doubt that spherical ones
could
K@� well, I'm just glad
I"m not a spherical chicken
K@�
too much wind resistance?
K@� not
aerodynamic enough likely
K@� I
suppose if you could accelerate the chicken to 75% the speed of
light..
K@� it'd probably fit in
the garage
Prabhu:
hahaha
**end transmission**
So what's a spherical chicken?
