Motion, Speed, & Velocity

Motion Motion is a change in position (relative to a reference point) *reference point- stationary (still) object

Conclusion Distance vs. Displacement Distance is the length of the path traveled. Displacement (from “dis”-place to “dat”-place) is the length and direction of a line from start to finish. Displacement is a vector quantity that contains both magnitude and direction.

Distance vs. Displacement -path that is traveled -change in position of an object -can be a straight line -must be a straight line -no particular direction -must always indicate direction is needed

Distance and Displacement 8km = Distance 3km = Displacement

Speed Speed- how fast something moves; must measure 2 quantities 1. distance- traveled by object 2. time- it took to travel that distance Speed equation S = d t Always remember units! d= meters, kilometers t= sec, min, h s= m/s, m/min, km/h Graphing speed= time on x-axis Distance on y-axis *The slope shows speed

3 types of Speed Instantaneous- rate of motion at any second Constant- speed that does not vary (most speeds are not constant) Average- total distance traveled divided by the total time (good at describing a bike or car trip)

Velocity Velocity- describes both speed & direction (east, west, north, south, up, or down) of an object Velocity can change even when the speed is constant, simply by changing directions V = d t