# Terminal Speed in Projectile Motion under Air Resistance

1. Nov 26, 2012

### th4450

1. The problem statement, all variables and given/known data
Terminal speed = 43 m s-1

2. Relevant equations
Acceleration in y direction when ball falling down: ay = - g + $\alpha$vvy
where $\alpha$ = K/m
and v = (vx2 + vy2)^0.5

3. The attempt at a solution
Putting ay = 0 as there is no acceleration when terminal speed occurs.
However, is vvy equal to v2, i.e. 432 here?
Or do I have to compute its velocity in the y direction?

2. Nov 26, 2012

### haruspex

When at terminal speed (near as dammit), what can you say about the horizontal component?