- #1

jgens

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## Homework Statement

A rocket ascends from rest in a uniform gravitational field by ejecting exhaust with constant speed u. Assume that the rate at which mass is expelled is given by dm/dt = km, where m is the instantaneous mass of the rocket and k is a constant, and that the rocket is retaded by air resistance with a force bv, where b is a constant. Find the velocity of the rocket as a function of time.

## Homework Equations

F

_{NET}= m*dv/dt - u*dm/dt

## The Attempt at a Solution

I've tried writing m as a function of t and using that in the rocket equation to solve for v, but I keep getting a really nasty differential equation. This course doesn't presuppose much knowledge about DEs, so I think that I must be doing something wrong. Can anyone point me in the right direction?