Final answer:
As two objects move closer due to gravity, their acceleration increases due to the gravitational force between them increasing as the distance decreases.
Step-by-step explanation:
The gravitational force between two objects increases as they move closer to each other, which results in an increase in acceleration for both objects. According to Newton's law of universal gravitation, the force between two masses is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers. Therefore, as the distance between the two objects decreases, the force exerted on each other increases, and so does their acceleration, assuming no other forces are acting on them. This principle can be applied to various physics problems, including those involving free-falling objects, where the acceleration due to gravity, g, is a constant that simplifies calculations when air resistance and friction are negligible.