Introduction:
The gravitational force between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. In this scenario, the mass and distance between the objects are doubled, and we need to determine the effect on the gravitational force between them.

Effect of doubling mass:
If the mass of both objects is doubled, the gravitational force between them will also be doubled. This is because the gravitational force is directly proportional to the product of their masses. Therefore, doubling the mass will result in a proportional increase in the gravitational force.

Effect of doubling distance:
If the distance between the two objects is doubled, the gravitational force between them will decrease by a factor of four. This is because the gravitational force is inversely proportional to the square of the distance between them. Therefore, doubling the distance will result in a proportional decrease in the gravitational force.

Combined effect:
In this scenario, both the mass and distance between the objects are doubled. Therefore, the effect on the gravitational force between them is a combination of the two effects mentioned above. Doubling the mass will result in a doubling of the gravitational force, whereas doubling the distance will result in a decrease in the gravitational force by a factor of four. Therefore, the net effect on the gravitational force between the objects will be a decrease by a factor of two.

Conclusion:
In conclusion, if the mass and mutual distance between two objects are doubled, the gravitational force between them will decrease by a factor of two. This is a combination of the effects of doubling the mass and doubling the distance between them.

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