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hankmensa99
Nov 5, 2006, 08:16 PM
If a person were weighed at the North Pole, would he weigh more than if he were weighed at the equator? How about if he were on an elevator to the center of the Earth, would he weigh more or less as he descended? Just curious. Hank

Ace High
Nov 5, 2006, 08:59 PM
Since the earth is not a perfect sphere, and bulges at the equator it would make the person at the equator a bit heavier. As the person progresses on the elevator to the center of the earth, he would have less mass under him and would gradually weigh less and less till he reaches zero ((or till he melts)) LOL. --- Ace

rajeevsrai
Nov 17, 2006, 11:18 PM
Right the person will weigh more on pole than on equator. Two reasons: earth's shape and rotation of earth about axis.

Capuchin
Nov 21, 2006, 07:17 AM
Just thought I should flesh out the answers above a little more.

There are two effects:

1. The amount of mass beneath you is greater at the equator, due to the oblateness of the Earth. This effect makes you weigh MORE at the equator.

2. At the equator, some of the gravitational force is needed to keep you on the Earth, to stop you floating off into space. This is the CENTRIPETAL FORCE. Since this effect is not present at the poles (the Earth doesn't rotate there) it makes you weight LESS at the equator.

When you factor in both of these effects, you find that g is about 9.83 m/s/s at the poles and 9.78 m/s/s at the equator.

So you weigh more at the poles.

Ace high is correct about travelling to the center of the Earth however, as g would decrease and hit 0 m/s/s when you hit the centre of the Earth.