- #1
scioly
- 18
- 0
Homework Statement
This isn't exactly homework...but I'm not sure where to post it. I was reading a textbook, and got myself in a mental predicament. I understand the reasons the book gave, but I want to *really* understand.
So my question:
"Why does air resistance decrease as the surface area to weight ratio decreases (i.e. same surface area, more weight)?"
(Specifically, I was thinking about why it takes less time for a coffee filter WITH paper clips in it to fall than it does WITHOUT any paper clips in it.)
Homework Equations
I haven't taken any physics really yet; I'm working on Electricity and Magnetism now (for fun), but that doesn't really help here...so I don't know any relevant equations.
The Attempt at a Solution
OK, so here was how I got myself in an "I understand this but I don't really understand this" state:
1) I know that a falling object is going to accelerate until it reaches its terminal velocity (that is, when the upward force of air resistance equals the downward pull of gravity)
2) I also know that, air resistance aside, gravity affects all objects equally (Galileo). BUT, when air resistance is an important factor, then different weighted objects (assuming constant weight) will fall at different speeds.
3) So the downward pull of gravity remains constant. This means that, somehow, the air resistance must decrease as the surface area-to-weight ratio decreases.
4) ...And here I got stuck.