# Homework Help: Calculus Question.

1. Nov 14, 2006

### bah

Calculus Question. Using velocity function to find acceleration?

The velocity of a falling body is v=8sqrt(s-t)+1 feet per second at the instant t(sec) the body has fallen s feet from its starting point. Show that the body's acceleration is 32 ft/sec^2.

Well, the derivative of the velocity function is acceleration, so it's v'=4(v-1)(s-t)^(-1/2)

How do I go from there?

Last edited: Nov 14, 2006
2. Nov 15, 2006

### neutrino

I don't know. The RHS of the given equation doesn't have a proper dimension.

3. Nov 15, 2006

### NateTG

Well, you know that:
$$v=8\sqrt{s-t}+1$$
so you could substitute that in for the $v$ in the second equation:
$$v'=4\frac{v-1}{\sqrt{s-t}}$$
It should work out nicely from there.