Hi,
I am kinda having trouble with the following problem:
Suppose that the acceleration of a model rocket is proportional to the difference between 120 ft/sec and the rocket's velocity. If it is initially at rest and its initial acceleration is 120 ft/sec^2, how long will it take to accelerate to 96 ft/s?
t = ______________ sec
What I have tried:
dv/dt=k(120-v)
integrating both sides:
-ln|120-v| = t + C
Since, t = 0 and initial velocity v = 0
Thus, C = -ln|120|
I am stuck here:
Please help,
Many thanks....