Ifwith
separation of variables gives
Ifat
we can integrate this:
Rearrangement gives
This motion is only defined forWhen
goes to infinity. Of course in any physical system the model will break down before this time. In general the motion is defined as terminating if it is represented by a solution of the motion which is undefined at some finite time.
If(1) then
which can be arranged to give
The system reachesat
No motion satisfying (1) is possible after this time and the motion terminates there.