PDA

View Full Version : OT Question



Zen--
02-16-2004, 07:26 PM
If you were to dig a hole straight through the center of the earth... clean to the other side, and then you jumped in, how long would it take you to fall out on the other side?

-Zen-
Formerly TX-Zen

Zen--
02-16-2004, 07:26 PM
If you were to dig a hole straight through the center of the earth... clean to the other side, and then you jumped in, how long would it take you to fall out on the other side?

-Zen-
Formerly TX-Zen

resev
02-16-2004, 07:34 PM
Of course its a joke, but allow me for a small reiteration.

If the hole was dug at sea level, then when falling, you would be conscient until about 3 miles or so deep, beyond that, you would blackout, and continue falling, while your body keep getting under more and more pressure, until eventualy, it would collapse on itself (implode).
This would happen far before ever reaching even halfway to the center.

http://mysite.freeserve.com/resev/images/2-picture2.gif?0.3524929147671928

Zeus-cat
02-16-2004, 09:00 PM
Not sure why you would black out. Not saying you wouldn't, just saying I don't see why you would unless you are attributing that to the pressure.

Lets say you lined the hole with a mtal pipe so we can avoid the pressure issue. How long would it take? I think you need to solve this with the calculus as gravity becomes a variable. 1G at sea level dropping to zero at the center of the earth and then increasing to 1G again as you approach China (assuming you jumped from the U.S.). The momentum you had as you passed through the center of the earth would take you to the other side of the planet (more or less ignoring air resistance). You would then proceed back through the center and come back to the place you started. Then back to China. You would oscillate back and forth forever unless we take air resistance into account. If you do look at air resistnace, then you wouldn't quite make it to China on the first go around. AS you came back to the States side of the planet you would lose a little more momentum. After 20 or 30 or 100 passes through the center of the earth you would stop there.

The reason you have zero G at the center of the earth is that you essentially have equal amounts of earth on all sides of you at the same time. Since gravity is directly related to mass and the distance that mass is from you, you have equal amounts of gravitational pull in all directions or a net effect of zero G at the center of the earth.

Another thing to think about, is that an average sized person sitting about 1 foot (30cm) away from you exerts more gravitational pull on you than the moon. Kind of puts a few holes in the old astrology thing don't it?

Zeus-cat