Will an object weigh more at the equator or at the poles? What two effects are at work and do these effects oppose each other?

Answer 1

The two factors are:

1. The rotation of the earth gives a tendency of objects (and people) to fly off, although this is largely offset by the force of gravity, and hence apparently reduces the weight. At the poles, this force does not exist.

2. The difference in the earth's radius, 22 km more at the equator, which reduces the value of g (9.81 m/s²) through the equation F=GMm/r².

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