An object travels North at # 8 m/s# for #3 s# and then travels South at # 6 m/s# for # 8 s#. What are the object's average speed and velocity?

1 Answer
Jul 23, 2017

The average speed is #=6.55ms^-1#
The average velocity is #=-2.18ms^-1#

Explanation:

The total distance travelled is #d=8*3+6*8=72m#

The total time is #t=3+8=11s#

The average speed is

#barv=d/t=72/11=6.55ms^-1#

The displacement is

#Deltax=8*3-6*8=-24m#

The average velocity is

#=(Deltax)/t=-24/11=-2.18ms^-1#