http://www.ck12.org Chapter 4. Motion and Forces
4.3 Direction
- State the importance of direction as a component of motion.
- Use a compass rose to determine direction on a map.
- Show how to represent direction and distance with vectors
Imagine traveling several miles in one of the directions indicated by this sign. Now suppose that a friend travels
the same distance in another direction indicated by the sign. You and your friend would end up in very different
locations. Obviously, direction is an important component of motion.
Introducing Direction
Direction can be described in relative terms, such as up, down, in, out, left, right, forward, backward, or sideways.
Direction can also be described with the cardinal directions: north, south, east, or west. On maps, cardinal directions
are indicated with a compass rose. You can see one in the bottom left corner of the map in theFigure4.4. You can
use the compass rose to find directions on the map. For example, to go to the school from Jordan’s house, you would
travel from east to west. If you wanted to go on to the post office, you would change direction at the school and then
travel from south to north.
Why Direction Is Important
Look again at the map in theFigure4.4. The distance from Jordan’s house to the post office is 3 km. But if Jordan
told a friend how to reach the post office from his house, he couldn’t just say “go 3 kilometers.” The friend might
end up at the park instead of the post office. Jordan would have to include direction as well as distance. He could
say, “go west for 2 kilometers and then go north for 1 kilometer.”