Q: Gravitational force acts on all objects in proportion to their masses. Why then, a heavy object does not fall faster than a light object ?
Sol: A freely falling object of any mass falls under the action of gravity given by g = GM/r2 where G is constant of gravitation, M is mass of Earth r is the distance between the object and the centre of Earth.
Thus, the acceleration due to gravity is independent of the mass of the objects.
∴ All objects fall with the same acceleration towards the earth.