Question

A man weighs 600N on the equator, but when he moves to the pole he finds a slight increase in his weight. This is because

• A. The radius of the Earth is less at poles since it is not a perfect sphere.
• B. The radius of the Earth is more at poles since it is not a perfect sphere.
• C. There is no increase or decrease in weight on the Earth.
• D. Can’t be said.

Answer 1

The correct option is A

The radius of the Earth is less at poles since it is not a perfect sphere.

g = $\frac{GM}{R^2}$​ and weight is the force due to gravity i.e mg.

Since, Earth is an imperfect sphere; its R is smaller at poles than at equators. As seen above, g is inversely proportional to R. Thus, the value of g increases at poles and hence weight of the body also increases.