If you dig a hole from the U.S. to China would you come out head or feet first?

Hi there,

Thanks for the headache, but I think I have found an easy way to
explain it. I have assumed that the digger is stupid enough to be
male, and that he prefers standing upright when digging.

The first thing you need to forget about is the idea of the hole being
dug straight down from the US and arriving in China as a vertical
hole. Although China is on the opposite side of the northern
hemisphere, the opposite side of the globe is actually the Indian
Ocean.

The digging would be at an angle to the surface. It would be like
digging a tunnel into a mountain, but at a very steep downward angle.
At the start the digger would be digging at his feet, and would be
going feet first into the hole. Halfway there the tunnel would be
parallel to the surface and the digger would be standing upright and
digging at a wall in front of him. As the digger approaches the
surface of China, the tunnel will be at a steep angle again, but
opposite to the original angle. The digger would be chipping away at
the earth above him, and he would come out head first.

It would be a very awkward angle to dig from, but not directly
downwards. The digger will be on his feet the entire journey, but his
feet will always be between his head and the centre of the earth.

If you imagine that the hole was already dug, and someone in China
climbed a few metres into the hole, and then climbed out again, how do
you picture them climbing out? That is the way the digger will emerge.

For a deeper understanding of this topic, I advise you to contact the
Chinese government, who are currently interrogating a US boy who dug
just such a hole:
http://www.shotgunreviews.com/features/boydigshole.html

A rabbit has also made the journey:
http://www.pausd.palo-alto.ca.us/hays/Obermayr/SM/chinaadventure/HopperChina.html


Search strategy:
"hole to china" "upside down"
://www.google.com/search?q=%22hole+to+china%22+%22upside+down%22


Best wishes,
robertskelton-ga

Thanks for the answer. It was a Science question given to earn extra
credit for an upcoming test.

The depth of the hole is unimportant.

Most people climbing out of any hole would choose to emerge head
first.

It's hardly practical to emerge from a hole legs first. For one thing,
you'd want to see what was up above.

While it is true that digging a hole through the center of the Earth
from most of the USA will land you in the Indian Ocean, I recall
reading that there is a small area of the USA that is directly
opposite a small area of China.

In any case, I agree that the only sensible way to dig would be to
re-orient yourself so that your feet are always pointing "down."  In
theory you could keep your body in the same orientation all the way,
and thus emerge feet-first, but standing on your hands and digging at
the ceiling with you feet would be slow going!

The USA is in the northern hemisphere, so is china.  If you are
digging straight down(up) from the northern hemisphere you'll end up
in the southern hemisphere.

I'm pretty sure that the Xerox Parc Map viewer used to have an option
to project both hemispheres onto a single surface,  giving an
fascinating view of what every point is opposite.  Sadly it seems to
have been withdrawn.