portal physics problem - 4chan
possible explanation (### SPOILER ###)
#
#
#
#
#
#
#
#
#
#
#
Actually, both is right. Or better: both is wrong. It's a paradox.
Here is why: imagine you are standing in a place where you could see the cube with direct line of sight AND through the portal.
now, since speed and momentum are vectors, their direction is of extreme importance:
if
the cube was to be propelled through the portal, in the direction where
you are standing (see pic), it need to have momentum / speed in exactly
this direction.
case a) you are watching the the cube in direct
line of sight: as the cube is put through the portal, you can clearly
see that it is not moving towards you at all. Hence there is no momentum
towards you, so why would the cube all of a sudden fly towards you.
case
b) you watch the cube through the portal: as the piston closes, you can
clearly see the cube coming closer to you, thus having momentum and you
would expect it to continue fly towards you because of inertia.
so far, so good.
case
c) what happens, if you do both at the same time? look at the cube
directly and then through the portal and then directly again?
exactly.
and
it's even worse, as you can see the room itself having momentum towards
you in case b which obviously doesn't make any sense, as you are not
moving in the room at all. it's paradox, hence it cannot even exist in
the first place.
it's like that painting of a staircase, that's always going up.
and
that, dear anons, is why portal was developed in a way where a
situation like this could never appear. it would just break everything.
and
yes, I know that there are moving portals in Portal 2, but you never
actually send something with mass (which is needed to have momentum)
through it while moving.
you are welcome.
oh, and if you don't believe me, watch this video:
http://www.youtube.com/watch?v=S85nudR6D-Yspoiler alert: engine freaks out, because paradox.