Originally Posted by
corrado33
Gravity is directly correlated with the inverse of the square of the distance the two objects are apart. (1/d^2)So, if you're at a higher elevation you'll feel less "gravity" than if you were at sea level. Also, gravity at sea level would vary considering the earth isn't a perfect sphere (it's "squat" because the earth spinning makes the equator slightly fatter than the rest of the planet.) Obviously the gravitation you feel is much more complicated that what I just said, but that's the gist.
Okay, but what about the effect of centripetal force at different latitudes? The earth is pear-shaped because of centripetal force, so why wouldn't the same force affect objects on the earth's surface? Even if the earth's gravity is far more powerful than the centripetal force at the equator, there should be some measurable difference in weight at the poles, no matter how small.
Correction: I should have said centrifugal force. Centripetal force in this case is gravity. Unless I'm hopelessly confused, centripetal and centrifugal force must be in balance, or an object will go spinning off into space. But why would gravity be stronger at the equator than elsewhere?
Relevance to bicycling: If you add Green Slime to your tires and don't give them a spin, what happens to the GS?