Final answer:
The gravitational force is greater between the two 2-kg masses that are 1 m apart than between the 1-kg and 2-kg masses that are 2 m apart due to the inverse square law and the product of the masses.
Step-by-step explanation:
To understand the force of gravity between the given pairs of objects, we can apply Newton's Universal Law of Gravitation, which states that the gravitational force (F) is directly proportional to the product of the two masses (m1 and m2) and inversely proportional to the square of the distance (r) between them. The formula is given by:
F = G * (m1 * m2) / r^2,
where G is the gravitational constant.
For the two situations provided:
1-kg and 2-kg masses 2 m apart: F = G * (1 * 2) / 2^2, F = G * 2 / 4 = G * 0.5.
Comparing these, the force between two 2-kg masses 1 m apart is greater than the force between a 1-kg and 2-kg mass 2 m apart.
Therefore, the correct answer is c. The force of gravity between the 1-kg and 2-kg masses is less than the force between the two 2-kg masses.