Question

How does the force of attraction between the two bodies depend upon their masses and distance between them? A student thought that two bricks tied together would fall faster than a single one under the action of gravity. Do you agree with his hypothesis or not? Comment.

Answer 1

Acceleration due to gravity: It is the acceleration a body experiences when no other force except gravitational force is acting on it.

It is given by, $g=\frac{GM}{r^2}$

1. The force of attraction between two bodies is given by Newton's law of universal gravitation.
2. It states that 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.
3. Acceleration due to gravity is given by $g=\frac{GM}{r^2}$
4. We can observe that it does not depend on the mass of the object.
5. Hence, irrespective of the mass of the body, they will reach the ground at the same time in a free-fall situation.
6. However, this happens only in vacuum conditions. In normal atmospheric conditions, air resistance plays a role and the heavier object will fall faster.
7. So, two bricks tied together would not fall faster than a single one under the action of gravity.
8. Therefore, the hypothesis is wrong.