Question

If the speed of rotation of earth about its axis increases, then the weight of the body at the equator will

• A. increase.
• B. decrease.
• C. remain unchanged.
• D. sometimes decrease and sometimes increase.

Answer 1

The correct option is B decrease.

This is due to the gravity's force is resolved into a centripetal force that acts parallel to the equator.
Thus, at the Poles, apparent weight is the same as mg.
At the equator, apparent weight will be $m{g}^{\prime }=m(g-R$${\omega }^2$)
Where $\omega$ is the angular velocity.