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The Science of a Bottomless Pit
StartsWithABang writes It's the ultimate dream of many children with time on their hands and their first leisurely attempt at digging: to go clear through the Earth to the other side, creating a bottomless pit. Most of us don't get very far in practice, but in theory, it should be possible to construct one, and consider what would happen to a very clever test subject who took all the proper precautions, and jumped right in. Here's what you would have to do to travel clear through the Earth, come out the other side, and make the return trip to right back where you started.
Interesting... What happens if you tunnel fro New York into an ocean on the other side of the world? Does the water drop in and boil in the centre of the Earth?
This very topic is discussed in "Entertaining Physics" printed first in 1912. And I'm sure it has been discussed even earlier.
Mathematically it's an example of a degenerate orbit with one zero semi-axis, and the orbital period can be simply calculated from Kepler's laws.
What's more interesting, it even holds true if you do not move through the center of the Earth! For example, a train from any place on Earth to any other place on Earth will move all by itself and always arrive at destination in about 45 minutes (neglecting the oblateness of the Earth and need to compensate for Coriolis forces and friction) if you put it inside a completely straight tunnel.
The article suggests that the earth's rotation would cause the dropped to hit the wall on the way down. So why can't the tunnel curve to account for this? Presumably it would curve the other way as it exits. It also suggests that going from North to South pole wouldn't work because of their relative altitudes, but is there an antipodal point where the altitudes are close enough feasibly go from one side to another - e.g. build a tunnel / raised platform to bring each side to the same altitude. I realise this is all completely hypothetical, bad movie remakes notwithstanding.
I actually live near a REAL one.
http://www.sciencebuzz.org/blo...
No, seriously, it's a hole in the ground, into which half of a decent-sized river dumps.
They have put everything from dye, to pingpong balls, to (amusingly) a car - and none of it has ever come up anywhere.
-Styopa
I always told my kids it takes longer to drive north because it's all uphill.
Interesting to watch their reactions over the years go from unquestioning acceptance, to cognitive dissonance. to enlightened disagreement, to "Daaaaaaad!!!", to "When are we stopping to dinner?'.
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
Fun fact, during the space race there was also a less well known "Drill race" between the Soviet Union and America to see who could dig down the farthest. The Soviets won this by a long shot and as always found a lot of things that changed what we know about the composition of the Earth's crust. Most notably the farther they went down they noticed that the mud that bubbled up contained hydrogen and lots of water. They also noticed that the rock type didn't change at those depths (the reason seismic waves travel around the center of the earth instead of through it). The rock actually began to behave more like plastic at those depths! Learn more here http://en.wikipedia.org/wiki/K...
"What happens if you tunnel fro New York into an ocean on the other side of the world?"
This is an interesting scenario. First, the amount of water it would take to fill the tunnel up to its center would be enough to slightly lower the water level, easing the flooding problem in places like Venice and Miami. The water near the center would boil, bubbling up through the water higher up in the tunnel to create a steady plume of steam at the surface. This would end up as increased cloud cover and precipitation over large parts of the world.