The gravitational field strength at the surface of a certain planet is g. Which of the following is the gravitational field strength at the surface of a planet with twice the radius and twice of the mass?

Options

A. `(g)/(2)`
B. g
C. 2g
D. 4g

Answer

A

Explanation

For a given planet, `g=(GM)/(R^2)`
Graviational field strength at the surface of another planet,
`g'=(GM')/(R'^2)`
Here `M'=2M,`
`R'=2R`
`thereforeg'=(G(2M))/((2R)^(2))=(g)/(2)`