How does gravity work at the core of the earth (or any planet)?

Question

I don't have an incredibly firm grasp on relativity, but its my understanding that all matter contains its own gravitational force and that a body's total grav force is proportional to its mass. We stick to the earth because all of its mass is below us. If one could stand in the center of the earth (without burning up, suffocating, etc.), what gravitational pull would they feel? Since they have equal mass surrounding them on all directions, would they be pulled apart? Or would they be crushed because gravity still pushes inward through some mechanism?

Answer 1

The gravitational effect at the centre of the earth due to the earth itself would be zero (more correctly, at the centre of gravity). This is because the pulls from any part of the earth would be balanced by it's mirror image at the other side of the earth which would exactly cancel it out.

You wouldn't be torn apart by the forces, because the pulls aren't pulling through you as such but are adding together as vectors, with only the resultant having an effect. However, because the resultant is zero, so is the force.

As you moved out from the centre, the gravity would increase until you reached the surface where it would become maximum. Then, if you carried away from the surface, it would then start to drop away again, finally dropping down to zero again as you reached infinity.

Answer 2

Zero gravity. There would be essentually an equal amount of mass surrounding you, hense, you would feel weightless. If you were to start walking straight in any direction, you would slowly feel the pull of gravity in the opposite direction increasing until you reached the surface - you would then feel the effect of the entire earth's gravitational pull.

Answer 3

It can be shown that, at any point below the earth's surface, the net gravitational force acting there is that equivalent to that of a sphere centered at the earth's center, and passing through the point in question. At the center of the earth, the diameter of the sphere would be zero and no net gravitational force would be felt.

Answer 4

particularly sufficient, in case you may desire to drill a hollow to Earth's midsection (with out annoying in regards to the crushing tension and boiling warmth) you will discover that the gravity might lessen as you went down. right this is why: once you're status on the exterior, all of Earth's mass is below you, pulling you in direction of the midsection. rather, it rather isn't completely genuine. a robust deal of Earth's mass is off to your sides, yet because of fact that it rather is dispensed extra or much less flippantly around you, it cancels out the sideways pull and it purely appears like a downward pull. in case you dig a hollow down into Earth, there's a robust deal of mass it rather is now ABOVE you, pulling up on you. This partly cancels out the mass below you. the maths are rather complicated, however the gravity of a shell surrounding you frequently cancels out, as long because of fact the shell is of extra or much less uniform density. once you attain the midsection, Earth's mass is dispensed the two around you, pulling the two in all guidelines. The gravitational tension from all that mass pulling in distinctive guidelines will cancel out to 0; you would be weightless on the precise midsection of Earth. Now enable's make sparkling something right here: in case you have been to decrease Earth down so as that it have been purely some miles huge and stand on it then, you will adventure a plenty, plenty extra beneficial gravitational tension. no longer purely might you nevertheless have all of Earth's mass "below" you, yet you would be plenty nearer to maximum of Earth's mass. Gravity will enhance as you get close to to an huge physique, so tiny-Earth might squash you flat! i'm hoping that enables. stable success!

Answer 5

To go farther - Zero gravity except for the falling around the sun.

Answer 6

Zero gravity

Answer 7

You would still be pulled to the center of gravity, in this case the exact center of the planet, so in theory, you would be crushed.