Problem

The force of gravity on a 2-kg rock is twice as great as that on a 1 -kg rock. Why then doesn't the heavier rock fall faster?

Problem 10Q

Solution 10Q:

We have to understand that why, motion of a falling object under gravity doesn’t depends upon the mass of an object.

Step 1 of 3</p>

Concept: From Newton's first law: An object of larger mass has a larger inertia and second law.

From Newton's second law: Acceleration of an object is the ratio of force to mass.

Step 2 of 3</p>

Under the action of force due to gravity, the force acting on the 2 kg object is twice as great in comparison to the force acting on the 1 kg rock due to gravity. So we can say, that the mass and in turn the inertia of the 2 kg rock is twice the mass (inertia) as that of the 1 kg rock.

Since, acceleration is the ratio of force to mass, so we can conclude that the two rocks should have the same acceleration.