Question

when a piece of paper and coin are dropped from the same height simultaneously the coin reaches the ground first and the paper takes some time in reaching the ground.If we crumple up the piece of paper in the form of a ball and let the two drop from the same height again they reach the ground almost at the same time.Explain the science behind this activity

Answer 1

The acceleration produced in freely falling bodies is the same for all the bodies and it does not depend on the mass of the falling body .But water and air are the most common fluids. There is a frictional force whenever an object moves through fluid It is called frictional force or drag.Drag opposes the motion of an object moving through them.Frictional force will be more if the surface area of objects is more. So
In case 1:
When paper (without crumpled) and coin are thrown, coin reaches first because paper experiences more frictional force as surface area of paper is more than coin.
In case 2:
Both coin and paper(crumpled) have almost same surface area so, same amount of frictional force is exerted hence both reach to ground at same time.