If the radius of the earth contracts to half of its present value without change in its mass, what will be the new duration of the day?

Options

A. `6` hours
B. `12` hours
C. `18` hours
D. `24` hours

Answer

A

Explanation

`momegaR^(2)="constant"`
`impliesomegaprop(1)/(R^(2))impliesTpropR^(2)`
`(T_(1))/(T_(2))=((R)/(R//2))^(2)=4`
implies `T_(2)=(24)/(4)=6` hr .