What is Jerk?
{{No sources|date=June 2020}} '''Jerk''' is the change in the [[acceleration]] of an [[wikt:object|object]]. Mathematically, jerk is the [[derivative (mathematics)|derivative]], or the rate of change of acceleration by time. Jerk is also called '''jolt''' (in British English), '''surge''', or '''lurch'''. Jerk is a [[vector]] and there is no word for its [[scalar]] value. The jerk is measured in [[metre]]s per [[second]] cubed (<math>m/s^3</math>). Yank can be thought as a [[Force (physics)|force]] in terms of jerk. Force is mass times acceleration. Similarly, Yank is mass times jerk. It is also the derivative of the [[Force (physics)|force]]. However, when an object is moving near the [[speed]] of light, a force is often written as the derivative of [[momentum]]. In this case, Yank is the rate of change of the derivative of [[momentum]]. == Its use == Jerk is used in [[engineering]], particularly in making [[roller coasters]]. Weak objects such as people can be damaged by high [[acceleration]] or high jerk. Also, jerk must be thought in the process of making any product. Sudden change in acceleration means very large jerk. Extent of exposure to jerk is often a good predictor of the rate of deterioration of tools while in normal use; it corresponds better to the appearance of metal fatigue among other modes of failure. [[Category:Mechanics]] [[Category:physical quantity]]