8th Grade Force and Motion Investigations 1-4 Summary Motion Review 8th Grade Force and Motion Investigations 1-4 Summary

Motion Review

Motion Review Position, represented by the symbol x, is the location of an object at any given time. Motion is the act of changing position. The Greek letter delta ( ) represents the concept of change. x represents change of position.

Distance and Position Distance is how far an object travels from an initial position (xi) to a final position (xf). d represents distance. A reference point is an arbitrary point on an object, used to establish position. Distance Equation: d = xf-xi

Air Trolleys Initial position vs. final position

Speed Review Speed is the distance an object travels in a unit of time. Speed Equation: v = d/ t

Comparing Speeds Average Speed: the total distance traveled by an object divided by the total time from start to finish. The slope of the line on a distance vs. time graph varies as speed changes; steeper slopes represent faster speeds.

Comparing Speeds Graph Who is faster, Gaston or Bert? How do you know?

Representing Motion Distance is the magnitude of the difference between initial position (xi) and a final position (xf). Displacement is the distance an object moves in a particular direction. Displacement can be positive or negative. Position graphs plot position vs. time; distance graphs plot distance vs. time. Complex motion events can be analyzed into coherent segments called legs. (ex: Iditarod)

Representing Motion The Alaskan Iditarod’s race is broken into legs.