Earth's Center and Gravity
Name: Ian Garioch
What is gravity like at the centre of the earth? If I dug
a hole through the earth and travelled to the centre would I be pulled in
both directions or float or what?
Yes, you would be pulled equally in all directions, in essence in "zero
gravity". But the temperatures in the center of the earth would melt all
known materials, you'd need some special insulating field to protect you
there. Getting there would be another issue, another question.
This is all a "what-if" journey, right?
You would oscillate between the center of the earth
and each end very much like a yo-yo.
At the center of the earth, you would not feel any gravity. This is
because the gravitational pull from every region of the earth is exactly
counteracted by the gravitational pull from the corresponding region on the
opposite side of you. This all adds up to a great bug zero.
Of course, you would perish in molten lava long before you reached the
center of the earth, but that's a different matter.
You would be pulled in all directions at the same time, which really means you
would be floating. Floating means that whereever you are, you would stay,
just, well, floating. Since you are getting pulled in all directions at once,
you don't move in any one direction at all, you stay put.
This all assumes that the earth around you is a perfect ball, a perfect
sphere. If it is not, then you might slowly move off in one direction or
Dr. S. Ross
If you managed to get to the centre of the earth (and please note that
travelling to the centre of the earth is not recommended for health reasons
- it is so hot that you would catch fire and be compressed by the enormous
pressure) you would be pulled equally in all directions at once...but you
would experience it as being weightless.
When I tell you that you would be pulled in all directions at once you
probably think of your arm being pulled one direction and your legs in
another and you head being pulled in entirely different direction. This
would not happen. Instead every tiny bit of your body would be pulled
equally in all directions at once and the forces would cancel each other
out. You would feel weightless because you cannot sense that there are
these competing forces which are cancelling each other.
In conclusion, if you go to the centre of the earth you will catch fire,
get squashed and will get space sickness because of the unusual sensation
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Update: June 2012