*How to perceive the duration of a force I am wondering how should I perceive the occurence of a force, at least while reading an introductory university physic textbook. When I try to think about basic vacuum environment examples of an object receiving a push, I always arrive at the dilema of visualizing how long did that push last. Was it instantaneous? Did it last half a second? A few seconds? Does it even matter? Knowing the magnitude of the force, the mass of the object, and the acceleration it underwent doesn't imply how long the force was applied for.