Science Chats Forum

I want to know about free fall.If I drop two things from a building with same shape and size but of different materials such as iron and paper.Which will fall first or they will fall at the same time?If I repeat the same activity in vaccum,what will happen?Also tell me , what is the factor in free fall.

Hey...
There are many examples of Free Fall in physics. I believe it was Galileo who introduced the subject of Free Fall. As you pointed out, so long as there is no air resistence, then two objects will fall at the same rate regardless of their mass.
A freely falling object is moving under the affects of gravity only. Take for instence an astronaut; they are in a state of Free Fall whilst they orbit the earth!
Another way to explain Free Fall is if we hypothetically flew to close to a Black Hole... The gravitational attraction would inexorably pull against the particles of our ship... But the force of gravity would also pull against the atoms am made of at the same rate... This is also a state of Free Fall.
Neo
P.S. If you drop Iron and paper, the Iron will hit the ground first. Again, there can be no wind resistence, and paper would have wind resistence.

What do you mean?If I drop iron and paper in vaccum,they will fall at the same time.Why? because there is no air resistance? And on earth if I drop these two things , iron will fall first.Why? because of mass?
WHAT MATTERS IN FREE FALL?

Well... Yes...
In space, air does not exist. If a piece of paper and a fabric of iron where to float around in orbit, they would be relative with each other... But closer to the gravitational fields such as earth's atmosphere, everything is pulled at the same rate, depending on whether there is any air-resistence... which there would be if you were to cast a piece of paper from a high location. The air resistence would penetrate the object, and iron would fall much more easily. For this reason, iron would reach the floor first.
I hope this answers your question:
Neo

What if I take aluminium and gold of same shape and size?Will gold fall first?

If aluminum and gold were to be shaped the EXACT same way, they will hit the ground at the same time.

__________________
Dorm Earning

If we shape paper and gold in the exact same way , will they fall at the same time?

The paper, i presume, would need to be air-tight... Though, based upon the fabric of paper, this would be almost impossible to do.
Neo

This means that if we take two object (except paper) of same shape and size and drop from a buliding , they will fall at the same time , in both conditions - in air and vaccum.ISN'T IT?

Correct.
Neo