# Motion of balloon

1. Dec 28, 2009

### skbay

I want to model the motion of balloon filled by a human not helium or any other gas.

what would be the equations? I know the air would've some mass so if I throw the balloon up that would f=ma ? distance = vt?

when a balloon comes down its downward motion is much slower say compare to a tiny metal piece, I assume thats because of low mass of balloon?

any other details would be appreciated.

2. Dec 28, 2009

### HallsofIvy

It is not really because of the low mass- all objects, of any mass, fall with the same acceleration in absence of air resistance. It is the large cross sectional area, pushing aside air, in combination with its low mass, that affects its acceleration.

3. Dec 29, 2009

### skbay

so then what equations do apply? how do i determine what is slowing the vertical velocity of balloon?

also I've noticed that everytime I throw the baloon up it tries to make it down such that its air noozle is pointing down (most of the time) more like a badminton shuttle, is this a given or only happens in certain scenarios?