1 Many instances of performance-based design are approved for their adherence to safety principles. 2  Ceremony implies honor, and honor implies an adherence to traditions. Many instances of performance-based design are approved for their adherence to safety principles. 2  Ceremony implies honor, and honor implies an adherence to traditions.
Acceleration is a vector quantity that is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity. Sports announcers will occasionally say that a person is accelerating if he/she is moving fast. Yet acceleration has nothing to do with going fast.
In other words, acceleration is the rate at which your velocity changes, because rates have time in the denominator. For acceleration, you see units of meters per second 2, centimeters per second 2, miles per second 2, feet per second 2, or even kilometers per hour 2. It may be easier, for a given problem, to use units such as mph/s (miles per hour per second).