Post date: Oct 11, 2015 6:50:51 AM
What happens when you drop something when there's no air resistance?
With only gravity acting on a pair of object, the objects will hit the ground at the same time. This has been shown on the moon with a hammer and feather; and more recently in the world's largest vacuum chamber (see video below).
There are three things to understand the reason the heavier object doesn't fall faster with no air resistance:
Only forces can change the speed of an object and we only have one force acting on the object: gravity (there's no air resistance).
There is a greater force downwards for objects with greater mass: this is an object's weight and due to gravity.
Objects with a greater mass will speed up more slowly. This is known as inertia and is the reason it's harder to push a bus than it is a car.
These two effects cancel one another out: a heavier object has a greater force downwards (due to gravity) but also is slower to speed up because it has more mass (inertia). Similarly, a lighter object has a smaller force pulling it down, but it's much easier to change its speed.