Chapter 8 - Rotational Motion and Equilibrium - Learning Path Questions and Exercises - Conceptual Questions - Page 302: 21

As a result of melting of polar ice caps, the mass in form of water, in lower latitudes would increase. Hence the moment of inertia of earth increases. So, to keep the angular momentum constant, the angular speed would decrease. So the earth would take more time to complete one rotation and hence the length of a day would increase.

As a result of melting of polar ice caps, the mass in form of water, in lower latitudes would increase. Hence the moment of inertia of earth increases. So, to keep the angular momentum constant, the angular speed would decrease. So the earth would take more time to complete one rotation and hence the length of a day would increase.