If the mass of a planet is `10%` less than that of the earth and the radius is `20%` greater than that of the earth, the acceleration due to gravity on the planet will be

Options

A. `5/8` times that on the surface of the earth
B. `3/4` times that on the surface of the earth
C. `1/2` times that on the surface of the earth
D. `9/10` times that on the surface of the earth

Answer

A

Explanation

`g_(p)=(G[M-10/100M])/([R+20/100R]^(2))=(Gxx9M)/10xx25/(36R^(2))=5/8g`