Chapter 8, Problem 15Q

To determine

To explain: The effect on the length of the day when there were a great migration of people towards the Earth’s equator.

Explanation of Solution

Introduction:

The angular momentum of a closed system is always constant. It means momentum is conserved.

When any person is standing on the equator, then mass of that person is far away from the axis of the rotation of the Earth as compared to the person stands anywhere else on the earth. Based on this, if more people are moving towards the earth equator, then more mass would be located far away from the axis of the earth rotation. This will result in increase in moment of inertia of the Earth. Based on the conservation of the angular momentum, as the moment of inertia of the earth increases, the speed of rotation of the earth is going to be decreases. So, earth would take more time to complete a full rotation or one day.

Conclusion:

Therefore,the length of the day will increase.