If there's a hole straight through the earth, from the south pole to the north pole?

Question

and you jump through it what would happen? would you keep falling forever, or fall back down when you get to the middle, or is it physically impossible?

Answer 1

Assuming a perfectly spherical earth with uniform mass density, then your acceleration towards the center is a linear function of your distance out from the center (a little bit of calculus and physics shows this).

So in this idealized case you get simple harmonic motion, I believe with period the same as the orbital rotation period of an object orbiting right at the earth's surface.

Dan

Answer 2

You would fall past half way, then bounce back toward the pole you started from on and on until you came to a stop at the center.

Technically, if there was no friction, you could keep bouncing forever, but assuming there is air in the hole, that would slow you down on each bounce.

Answer 3

It is impossible but at the centre of the earth there is no gravity.

Answer 4

u'll fall righ to the center and stay there forever........