I asked a quesion about this a while back, but I never felt that I got a perfectly straight answer. I want to know if there is any real physical situation where there is a constant jerk (third derivative of displacement with respect to time). I am perfectly aware of how common jerk is as well as countless higher derivatives. I actually want to know if there is something as simple as a constant force causing a constant acceleration. In other words, is there any physical situation where a force increases constantly and linearly over some non infinitesimal time interval?