Question

Suppose a planet has its mass twise that of Earth and radius 3 times that of the radius of Earth. find the acceleration due to gravity on that planet.

Answer 1

Answer:

acceleration on that planet due to gravity = 2.177 m/s²

Explanation:

Let, acceleration due to gravity on earth be g = 9.8 m/s²

Let, acceleration due to gravity on that planet be g' m/s²

From Universal law of gravitation.

g = Gm/r² -(i)

where, G = universal gravitational constant.

m = mass of the earth.

r = radius of the earth.

g' = Gm'/r'² -(ii)

Where, G = universal gravitational constant.

m' = mass of that planet. = 2m

r' = radius of that planet. = 3r

Putting value in equation (ii)

g' = G(2m)/9r² -(iii)

On solving (i) & (iii)

we, get g' = 2.177 m/s²