1. The problem statement, all variables and given/known data A rocket ascends from rest in Earth's gravitational field, by ejecting exhaust with constant speed u. Assume that the rate at which mass is expelled is given by dm/dt = −γm where m is the instantaneous mass of the rocket and γ is a constant; and that the rocket is retarded by air resistance with a force mbv where b is a constant. Determine the velocity of the rocket as a function of time. Here is a hint: The terminal velocity is ( γu−g )/b. Calculate the time when the velocity is one-half of the terminal velocity. Data: u = 31.9 m/s; b = 1.2 s−1. 2. Relevant equations dp/dt=m(dv/dt) 3. The attempt at a solution I got the diff eq down to: dv=-u(dm/m)-(g+bv)dt I'm not quite sure what I am doing wrong, I divide by -(g+bv) then solve from there to get -b*ln(g+bv)=uγt, but for some reason I dont think this is correct. Help, thanks.