# Drag force/difficult integral.

## Homework Statement

If a ping pong ball is released from rest, how long does it take for the ping pong ball to reach 90% of its terminal velocity?

m=2.2g, density(air)=a.29kg/m^3, Cw=.5, diameter=.38mm

## Homework Equations

Fd=1/2*C$$_{w}$$+$$\rho$$*A*v^2

newton's second law

## The Attempt at a Solution

I set up newtons second law for the going down case. I wanted to get v in terms of t.
I can't solve the integral though.

Fd-mg=m*dv/dt

$$\int \frac{dt}{m}$$=$$\int \frac{2*dv}{C_{w}*\rho*A*v^2-mg}$$

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