# Acceleration question

1. Sep 1, 2005

### ludi_srbin

What acceleration does a rocket need to reach speed of 200 m/s at height of 1.0km. I know that acceleration is velocity over time but I have only velocity and distance.

2. Sep 1, 2005

### VietDao29

$$v_f ^ 2 = v_i ^ 2 + 2ad$$? Do you know this formula?
Can you go from there? Remember to change 1.0 km into 1000m.
Viet Dao,

3. Sep 1, 2005

### ludi_srbin

That is calculus. Would you mind telling me those variables.

4. Sep 1, 2005

### VietDao29

a : acceleration (m / s ^ 2) = ?.
d : displacement (m) = 1000 m.
v_i : initial velocity (m / s) = 0 m / s (The object accelerates from rest).
v_f : final velocity (m / s) = 200 m / s.
Can you go from here?
By the way, I think it is physics, not calculus...
Viet Dao,

5. Sep 1, 2005

### ludi_srbin

O thanks. I tried to look it up in some later chapters but found formulas involving derivations. I didn't know what those variables were so I guessed that you have to use calculus to find way to do it. Thanks for help.