Weightlessness

When an object is dropped, it accelerates toward the center of the Earth. If the net external force on the object is its weight, it is said to be in free fall; that is, the only force acting on the object is gravity. Galileo was instrumental in showing that, in the absence of air resistance, all objects fall with the same acceleration g...

Recall that if the frictional effects of air are ignored, all bodies irrespective of their masses, fall with a constant acceleration known as acceleration due to gravity.

Such bodies are called freely falling bodies and the net force acting on them is only due to their weight. They reach the ground at the same time.

Hence, in the a...