# Terminal velocity

1. Jan 3, 2006

### ElDavidas

hi again,

I'm pretty sure I understand the concept of terminal velocity in that there is an upper limit to the speed of a falling body. How do you calculate the terminal velocity of an equation?

For example:

$$v = \frac {g} {\beta}( e^{- \beta t} - 1)$$

v represents velocity

2. Jan 3, 2006

### Staff: Mentor

Don't know what you mean by "terminal velocity of an equation", but if that expression gives the speed as a function of time then just let $$t \rightarrow \infty$$.

3. Jan 3, 2006

### Mindscrape

What does all that represent?

4. Jan 3, 2006

### fleon

Hi ElDavidas

I think that understand your question. I just know that this concept is relative, it means, in the context of falling bodies the formulae could be deduced theoretically, but however, the constants like your beta is determined only experimentally. Do you like another answer or is sufficient?

5. Jan 3, 2006

### vaishakh

I think you need the terminal velocity of a free falling object. For any fluids, here air we have an equation that CpAv^2 = D where D is the drag force applied by the fluid on the object in a direction opposite to the relative motion of the first object. Now mg - D = ma. So a becomes zero when????(better now you do the rest) So that is how you get it.