crash physics prep(3)

It is the speed of a moving object relative to a constant or a moving observer.

• speed

• Relative speed

• average speed

the relative speed = The real (actual) speed of the object.

• The observer is at rest

• The observer is moving in the opposite direction of the moving object.

• The observer is moving in the same direction at different speed.

the relative speed = The difference between the two speeds = Zero

• the observer is moving in the same direction at the same speed.

• the observer is at rest

• The observer is moving in the opposite direction of the moving object

It is the distance moved through a unit time. or It is the rate of change of distance.

• speed

• relative speed

• average speed

It is the change of an object position (location) as time passes according to the position of another object.

• speed

• Motion

• relative speed

It is the motion in which the object's position is changed relative to a fixed point from time to time between initial and final positions

• Transitional motion

• Periodic motion

• speed