Question

A planet of density double than that of earth but has a radius equal to that of earth. What is the acceleration due to gravity on that planet in terms of G,g ? ​

Answer 1

Explanation:

Here's the answer.

Hope it will help you.

Answer 2

Answer: 2g.

Explanation: Let the density of Earth be = (d). So, density of the second planet = (2d). And, volume of earth = volume of planet = V (assume). It is also given that radius of two objects are same.

We know, m = ρV

m (Earth) = dV and m′ (planet) = 2dV.

Now we know,

mg = GMm/R^2

• Acceleration due to gravity of earth = g = GM/R^2
• Acceleration due to gravity in planet = g′ = 2GM/R^2 = 2g.

So, acceleration due to gravity in the planet is twice of that of the Earth. (On the surface.)