How does gravity change as one goes down into a mine shaft or up a mountain?

Answer 1

It gets less the deeper you go until at the center of the Earth there is no gravity.

As you descend into a tunnel the net gravity you feel is only that force due to the mass of the sphere under your feet ... I did plent of physics calculus problems to prove this.

Answer 2

I could be wrong about this, but I imagine that going deep inside the Earth would actually decrease gravity. For the sake of calculation, the gravitational acceleration is computed as if the Earth were a point mass, but it is not. At any given seperation from the Earth (meaning that you're outside of it), then the entire mass of Earth is to some direction from you (usually, down - heh), and the net result of the effect is that you are attracted to the point where the center of the mass is located.

However, once inside the Earth, there are portions of it in all directions, pulling you toward them. The parts "above" you would be cancelling out some fraction of the parts "below" you, which means that the net force of gravity would be slightly less than it would be at the surface of the Earth.

If you dug a shaft all the way through the exact center of gravity of the Earth (and let's pretend the core isn't molten, so you can survive there) and jumped in, you would fall to the center and your momentum would carry you past it a while, but then you would fall back down again - back and forth like a pendulum until you eventually come to rest at the center of gravity of the Earth, where all parts of the Earth's mass were pulling you in all directions equally.

Answer 3

As you go down into a mine, gravity force get weaker. That's because part of the Earth is above you, and only the part that is below you, closer to the center of the Earth, pulls on you.

(Actually, the part that is above you pulls on you too, but it is canceled out by the same thickness on the other side of the Earth!)

On the other hand, as you go up a mountain, practically all of the Earth is below you all the time. The part of the mountain that is above you is such a tiny tiny fraction of the whole Earth, that it's gravity doesn't count for much. So the most important effect is that you are going away from the center of the Earth, so gravity force gets weaker.

That means that gravity is strongest at the surface of the Earth, and gets weaker as you go up or down.

Answer 4

As you go up a mountain, you're getting further from the centre of the earth, so it reduces, but only very slightly. Even on the highest mountain in the world, the difference is less 3 parts in a thousand. You wouldn't notice any difference.

As you go down a mine, gravity reduces also, because hte parts of the earth above your head cancel out some of the gravity. Underground, the force is proportional to your distance from the centre of the earth, so half way to the centre, it would be reduced to half. This effect is even less than the one up the mountain. In a mine that was as deep as the highest mountain is high, your wieght would be reduced by just over one part in a thousand.

Answer 5

The earths core is much denser than the surface crust. So, mass is concentrated more there. Gravity is therefore stronger until you get deep inside the center of the Earth. (Deep means hundreds of miles or more )

Answer 6

On a mountain the force of gravity (acceleration due to gravity) increases because there is more mass under you or the object which means your acceleration towards the mass is greater. In a mine the opposite happens because there is less mass under you.

(Gm1m2)/(r^2)= g or acceleration due to gravity

Answer 7

Closer to center of Earth - greater gravitational attraction.

Farther away from center of Earth - less gravitational attraction.

Answer 8

Not substantially.