a tunnel went thru the earth ,from one pole to the other, and you fell in it, would you stop in center ?

Question

so the tunnel goes straight thru the earth, from north pole to south pole, and you fall in ,after falling "down" all the way to the center, you would be falling "up," so would you float endlessly in the center ?

Answer 1

Dang, such literal-minded folks. Of COURSE you'd burn up. and you couldn't create a "tunnel" through molten rock, and yadda yadda yadda.
However, if you could create a tunnel from pole to pole (or from any point to the point on the opposite side of the globe running through the core) you would initially fall a fair distance through the core, then fall back a shorter distance beyond the core, then fall forward a shorter distance still, and eventually you'd hang suspended at the center of mass.
Of course, all this assumes that the Earth is a sphere (it isn't) that the center of the planet is the center of mass (it isn't) that gravity is uniform (it isn't) and that all other characteristics of a hole that deep (pressure and heat, mostly) would be of no impact (they wouldn't).
But if they WERE all true, hypothetically, then you'd end up hanging in the center of the Earth. And would't you feel silly?

Answer 2

You got some goofy answers already. Lets assume that a tunnel could be constructed. There are two scenarios.

First, if you leave the tunnel expose to the atmosphere, air would suck itself into the tunnel until the pressure equilibrated with the surface atmospheric pressure. The center of the tunnel would certainly be under enough pressure to liquefy gasses in the air. Hence, you wouldn't get far in free fall.

If you somehow avoided this (hypothetically), and had normal surface air pressure throughout the tunnel, you would quickly reach terminal velocity. At 180 kph, it would take some thirty five hours to reach the center. And it is doubtful that you would even overshot the center since the gravitational potential reaches equivalence there and drag forces will easily overcome your momentum.

Now, for the second case, if the tunnel were a vacuum, you would simply oscillate between the two poles forever, until something else happened.

Hope this helps.

Answer 3

Would it depend on whether the Earth would still be able to stay in it's normal orbit? If you took a great chunk out of the Earth then maybe it would go spinning off into space and we'd all be dead.

It's a bit hot down at the Earth's core so perhaps if the tunnel was built using a material resistant to heat then you would fall right to the centre and float around there until you died.

Whatever the consequence you'd have to be rather daft to miss a tunnel which goes from pole to pole

Answer 4

You'd be in trouble if you hit the tunnel wall whilst you were falling in! Apart from that, and from everyone elses answers ;) I like the idea that you'd swing about for a little falling up and down due to the speed of your fall, before eventually coming to a stop in a zero-G float.

I also like the idea that there are magic kingdoms hidden in the centre of the earth though... Arthur Conan Doyle did a great story called 'The Day The Earth Screamed'... it turned out that Earth was actually just a huge shellfish, and the surface was just its shell. In the story, Professor Challenger dug a great mine shaft down through the shell, and stabbed the urchin inside with a drill bit to wake it up! The resulting scream was deafening, and lots of volcanos erupted, and there were earthquakes and things.


In that scenario, if you dived down this tunnel, you might just end up in the belly of the jellyfish- mmmmm!

Answer 5

Worked this out once.

You'd oscillate about the centre of the earth with simple harmonic motion, SHM. The velocity would be a maximum at the center and zero at the two surfaces.

SHM is like a pendulum the acceleration is always towards the center and proportional to the distance from the center: acc = -w^2.x, where w^2 is a constant.

Answer 6

Remember that the air pressure will be very high when you are deep in the hole. Even at the surface of the earth, under a mere 1 atmosphere of pressure, terminal velocity is only 125 mph. As you approach the center, the atmospheric pressure will really increase. According to 1 calculator I found, even at 100 km below sea level, atmospheric pressure would be 88,700 times that at sea level. So, terminal velocity at that pressure would be about 7 feet per hour. Also, the force of gravity will decrease to zero as you approach the center. So by the time you reach the center you will hardly be moving at all.

Answer 7

No due to the incredible temperatures and pressures withi the earths core your body would have melted way before you got there and become part of the earths molten core.

However if you did make it there is no gravitational PULL at the exact centre but massive PUSH from all directions keeping you there.

The last problem is that the exact centre of the planet is constantly moving due to the fact that the earth isnt a perfect spheroid so due to the rotation of the earth you could never be in the exact centre for more that a fraction of a second.

Answer 8

First time you would go through the center but not all the way up. You would stop and fall in the other way and still not stopping in the center. With each passing the center the place of your stopping would be closer to it. After some time you would stop in the center and float like in zero gravity space.

Answer 9

Theoretically yes, if you didn't melt due to the heat, or get crushed due to the pressure first. Gravity exists when two objects are separated by a distance. If you were at the center of the earth, you would be equally separated from the earth's pull on al sides. The forces acting on you would cancel each other out and you would go nowhere!

Answer 10

You would oscillate from one side to the other assuming of course you ignore all heat related and other practical problems (as this is purely hypothetical). The oscillation would suffer from attenuation though as drag from the surrounding atmosphere acts upon you untill you eventually come to rest in the centre (or rather somewhere near there... the earth isn't a perfect sphere with homogenous density so you'd probably end up slightly off centre somewhere).