7 Position Motion Describing Position Reference point the

7. Position & Motion

Describing Position Reference point: the starting point you choose to describe the location or position of an object Position: distance and direction from the reference point Reference direction: the positive (+) direction The opposite direction is the negative (-) direction

Describing changes in position Motion is the process of changing position Distance is the length of the path traveled Displacement is the difference between the initial and the final position of an object

Practice Problems: Draw a diagram for each situation. Calculate the distance and displacement in each. 1. Amy runs 2 km south, then turns around and runs 3 km north. 2. Jermaine runs exactly 2 laps around a 400 meter track. 3. Ray runs 30 meters north, 30 meters west, and then 30 meters south. 4. James spins around 5 times without moving any direction. 5. Desmond walks 2 km north from his house to the park, then returns home. 6. Sandy ran 8 blocks north, and then 2 blocks south back toward her starting point. 7. Anslee swam 3 complete laps in a 50 meter pool. (1 lap is one length of the pool) 8. Alex walks east 3 km, stops for a break, and then runs the same direction for 4 km before he stops. 9. Taylor rides her bike 20 km north, turns around, and then rides her bike 15 km back toward her starting point.