An object travels North at #7 m/s# for #8 s# and then travels South at #6 m/s# for # 4 s#. What are the object's average speed and velocity?

1 Answer
Aug 14, 2017

The average speed is #=6.67ms^-1#
The average velocity is #=2.67ms^-1#

Explanation:

The total distance travelled is #d=(7*8)+(6*4)=56+24=80m#

The total time is #t=8+4=12s#

The average speed is

#barv=d/t=80/12=6.67ms^-1#

The displacement is

#Deltax=(7*8)-(6*4)=56-24=32m#

The average velocity is

#=(Deltax)/t=|32|/12=2.67ms^-1#