Question

anyone can help me solve pole vaulter's paradox?

Answer 1

ok, one door or two doors?

Answer 2

one door

Answer 3

ah, that one is trickier

this is gonna be FUN!

Answer 4

pls help, I'm so confused now...

Answer 5

do you need numbers? or will an explanation do?

Answer 6

v=0.8c, pole=4m, barn=3m

Answer 7

im stuck on the pole head reaches wall part..

Answer 8

ok
\[F={dp\over dt}\]

Answer 9

wut....??? i don't get it..

Answer 10

ok, so F = ma right?
now classically p=mv
so F=m dv/dt

Answer 11

make sense

Answer 12

then?

Answer 13

so F=dp/dt
now relativistically
\[\huge \vec p = \gamma m \vec v\]

so \[\huge \vec F = {d{(\gamma mv)} \over {dt}}\]
Once you do the calculus

\[\huge \vec F = {m\vec a\over \gamma ^3}\]

You'll need this in a bit

Answer 14

Now in the reference frame of the barn, through length contraction the pole will contract thus allowing it to fit right?

Answer 15

In the reference frame of the pole, the barn ALSO CONTRACTS

Answer 16

but here's the kicker. The pole collides with the wall

Answer 17

i know that.. and the tail is not gonna stop immediately..

Answer 18

so the pole will deform

Answer 19

and since the force of impact can only travel down the length of the pole at the speed of light, the end of the pole doesn't know that the front has impact the wall

Answer 20

Making sense?

Answer 21

I've never actually performed the mathematical calculation but I know what it involves. So I can only kind of guide you.

Answer 22

i think i need to see the actual calculation. but it's ok. thanks

Answer 23

oww, my pride lol
@ybarrap
@raffle_snaffle