Question

A newly discovered-planet is found to have a gravitational acceleration of 16 m/s2 at the surface. The radius of the planet is double the radius of Earth. The mass of this planet is most nearly

Answer 1

The mass of the planet is obtained as 3 *
`10^{18`Kg.

What is the acceleration due to gravity?

This is the the acceleration experienced by an object in free fall near the planet's surface due to the gravitational attraction between the object and the planet.

Given that;

g = GM/
`r^2`

g = acceleration due to gravity

G = gravitational constant

M = mass of the planet

r = radius of the planet

When;

g = 16

M = mp

r = 2re

Then

16 = Gmp/2re

mp = 16 * 2 * 6371000/6.7 *
`10^{-11`

mp = 3 *
`10^{18`Kg