An object travels North at #8 ms^-1# for #7 s# and then travels South at #7 ms^-1# for #3 s#. What are the object's average speed and velocity?

1 Answer
Apr 24, 2016

Average speed:

#speed=("distance")/(time)=56/10=5.6# #ms^-1#

Average velocity:

#velocity=("displacement")/(time)=21/10=2.1# #ms^-1#

Explanation:

In brief, the average speed relates to the distance traveled, the average velocity to the displacement.

Distance traveled North: #d=vt=8*7=56# #m#
Distance traveled South: #d=vt=7*3=21# #m#

Total distance traveled: #77# #m#
Displacement: #35# #m#

Total time taken: #10# #s#

Average speed:

#speed=("distance")/(time)=56/10=5.6# #ms^-1#

Average velocity:

#velocity=("displacement")/(time)=21/10=2.1# #ms^-1#