(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Derive an equation for velocity based on time with drag.

2. Relevant equations

The equation is: v(t) = F/b (1 - e^(-bt/m))

3. The attempt at a solution

There's some math on paper, but I got down to:

F - bv = ma

a = dv / dt

F - bv = m*dv/dt

dt = m*dv / (F - bv)

integrate both sides

t = m*(-ln(|bv-F|) / b)

-tb/m = ln(|bv-F|)

e^(-tb/m) = |bv-F|

here is where I don't know how to simplify it anymore. What do I do with the absolute value?

If I ignore it, it doesn't simplify right, or at least I can't get it to.

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# Homework Help: Deriving velocty with drag equation

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