Question

Why does the weight of a body vary from poles to equator?

Answer 1

The value of acceleration due to gravity g is least at the equator and maximum at the poles. The reason for this is explained below :

As we know that  g  α 1R2, where R is the radius of the earth.
And we know that Earth is not a perfect square. It is flattened at the poles and bulges at the equator. Equitorial radius Re of the earth is about 21 km greater than the polar radius Rp.  That's why, at poles, the value of g is greater as compared to the value of g at equator.

As we know that weight of a body = mass of body X acceleration due to gravity.

If the  object which is to be weighted is taken to the poles, then the weight of the object will increase and if it is taken to the equator, then its weight will decrease, as the value of acceleration due to gravity increases as we go from equator to the poles.

Answer 2

it is flattened at the polesand bulges at the equator.equilateral radiusof the earth is about 21 km greater than the Polar radius that's why the value of g is greater at poles as compared to the value of g at equater