How would doubling the mass of Earth affect the gravity we experience?

The strength of the gravitational force between two objects depends on two factors, mass and distance. the force of gravity the masses exert on each other. If one of the masses is doubled, the force of gravity between the objects is doubled. increases, the force of gravity decreases

Explanation:

if the mass or both of the objects is doubled, then the force of gravity between them is quadrupled and so on. Since gravayional force is inversely proportional to the square of separation distance between two interacting objects, more separation distance will result in weaker gravitational forces.

the bal will not change its velocity.

3. dark matter

empty space could also be a simple vacuum