An object travels North at #5 m/s# for #8 s# and then travels South at #8 m/s# for #4 s#. What are the object's average speed and velocity?

1 Answer
Aug 5, 2017

The average speed is #=6ms^-1#
The average velocity is #=0.67ms^-1#

Explanation:

The total distance travelled is #d=(5*8)+(8*4)=40+32=72m#

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

The average speed is

#barv=d/t=72/12=6ms^-1#

The displacement is

#Deltax=(5*8)-(8*4)=40-32=8m#

The average velocity is

#=(Deltax)/t=8/12=0.67ms^-1#