# An object travels North at 6 m/s for 2 s and then travels South at 1 m/s for 4 s. What are the object's average speed and velocity?

Jul 10, 2016

The average velocity is $\frac{4}{3}$ m/s toward the North.

#### Explanation:

The average speed of the object is simply the total displacement divided by the total time. Since the object first moves North for two seconds at 6 m/s, the object is displaced 12 meters to the North.

After moving South at 1 m/s for 4 seconds, the object now has a total displacement of 8 meters to the North.

The average speed then is:
$\frac{8}{6} = \frac{4}{3}$ m/s

And the velocity is simply the average speed in the direction traveled, North.