Question

Due to global warming, ice on polar caps is likely to melt in larger quantity. Due to this effect

• A. Moment of inertia of earth shall decrease
• B. Angular momentum of earth shall decrease
• C. Angular velocity of earth shall increase
• D. Length of the day shall increase

Answer 1

The correct option is D Length of the day shall increase

Answer (2)
Due to ice melting, water will tend to shift towards equator, this will increase the moment of inertia of earth. Since there is no external torque acting, therefore angular momentum of earth will remain conserved.
Hence, from $I\omega =\text{constant}$
As $I\to \text{increases}\to \omega \to \text{decreases}i.e.,$
Time period increase. Hence, length of day will increase.