I am trying to describe the evolution of a motion which is composed of smooth parts called "free flights" and instantaneous impacts. For example, consider a bouncing ball: its motion is a succession of free flights, separated with impacts (when the ball touches the ground).
I would like to refer to two time-related quantities: the duration of free flights, and the dates of impacts. The word "time" can refer to a length of time, or an instant (a date). To raise the ambiguity, I have chosen the following terminology:
- "free-flight durations" describes a length of time between two impacts;
- "impact times" describes the date of impact.
Is this correct and would "impact instants" or "impact dates" be better? I am open to other suggestions too, but I want to avoid "period" which I am already using to qualify repetitiveness.