1. Distance and Displacement Chapter 11.1

2. Motion • An object is in motion when its distance from another object is changing. • If no chance than no motion is perceived

3. Frame of Reference • Frame of reference is a place or object that you assume is fixed • observations of how objects move in relation to that frame of reference. • perception of motion depends on the observers frame of reference. • Humans usually use the earth as their frame of reference.

4. Measuring Distance • Distance: The length of a path between 2 points. • Distance is measured according to the amount of distance involved • EX: • Marble rolls= mm or cm (millimeters or centimeters) • Car travels= m or Km ( meters or kilometers)

5. Displacement • Displacement: the direction from the starting point and the length of a strait line from the starting point to the ending point. • Displacement is what we use to give people directions to our house. • Ex: walk north 5 blocks from the school take a right a distance with a direction associated with it

6. Displacement Vs distance displacement distance

7. Combining Displacements • An example of this is a vector. • This is a quantity that has a magnitude and a direction • Magnitude= size length or amount • Arrows on a graph are used to represent vectors. • The length of an arrow shows the magnitude of a vector

8. Examples Combining displacements • Vector addition is the combining of vector magnitudes and directions • EX: 5km 10km 5 + 10= 15km 10km 3km 10 – 3= 7 km