Question

If polar ice caps melt, then the angular velocity of rotation of earth

• A. Increases
• B. Decreases
• C. Remains constant
• D. Becomes zero

Answer 1

The correct option is B

Decreases

If the polar ice cap melts, the mass accumulation on the outer regions of the earth increases, so its moment of inertia increases
$\therefore$ conserving angular momentum,
$I_1{\omega }_1=I_2{\omega }_2$
${\omega }_2=\frac{I_1{\omega }_1}{I_2}$
As '$I_2$' is more, '${\omega }_2$' is less