direction

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 the Figure 1.1. You can use the compass rose to find directions on the map. For example, to go to the school from Jordans 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.

motion and vectors

When both distance and direction are considered, motion can be represented by a vector. A vector is a measurement that has both size and direction. It may be represented by an arrow. If you are representing motion with an arrow, the length of the arrow represents distance, and the way the arrow points represents direction. The red arrows on the map in the Figure 1.1 are vectors for Jordans route from his house to the school and from the school to the post office. Q: How would you draw arrows to represent the distances and directions from the post office to the park on the map in the Figure 1.1? A: The vectors would look like this:

why direction is important

Look again at the map in the Figure 1.1. The distance from Jordans house to the post office is 3 km. But if Jordan told a friend how to reach the post office from his house, he couldnt 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.

textbook_image

instructional diagrams

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questions

terms used to describe relative direction include

a) in.

b) up.

c) sideways.

-->  d) all of the above

the direction of motion is a vector.

a. true

-->  b. false

if you are facing north, then east is to your

a) left.

-->  b) right.

c) back.

d) none of the above

diagram questions

No diagram questions associated with this lesson