# An object travels North at  2 m/s for 6 s and then travels South at  7 m/s for  4 s. What are the object's average speed and velocity?

Clearly,distance covered by the object in total $10 s$ is $6 \cdot 2 + 7 \cdot 4 = 40 m$
So,average speed = total distance covered/total time taken = $\frac{40}{10} = 4 m {s}^{-} 1$
Again, net displacement is $\left(6 \cdot 2 - 7 \cdot 4\right) = - 16 m$
So,average velocity = net displacement/total time taken = $- \frac{16}{10} = - 1.6 m {s}^{-} 1$