Earth is revolving around the sun. If the distance of the earth from the sun is reduced to 1/4th of the present distance then the day length reduced to :

Options

A. `1//4`
B. `1//8`
C. `1//2`
D. `1//6`

Answer

B

Explanation

By Kepler.s third law `T^(2) prop r^(3)`
`therefore (T_(2))/(T_(1))=((r_(2))/(r_(1)))^(3//2)=((r//4)/(r ))^(3//2)=(1)/(8)`
`therefore T_(2)=(T_(1))/(8)`
Thus correct choice is (b).