An object travels North at #1# #ms^-1# for #3# #s# and then travels South at #7# #ms^-1# for #5# #s#. What are the object's average speed and velocity?

1 Answer
May 23, 2016

Answer:

The average speed is the total distance traveled divided by the total time: #"speed"="distance"/"time"=38/8=4.75# #ms^-1#

The average velocity is the final displacement divided by the total time: #"velocity"="displacement"/"time"=32/8=4.0# #ms^-1#

Explanation:

The average speed is the total distance traveled divided by the total time, while the average velocity is the final displacement divided by the total time.

The total time is #8# #s#.

The distance traveled in the first #3# #s# is #d=vt=1*3=3# #m# North.

The distance traveled in the next #5# #s# is #d=vt=7*5=35# #m# South.

The total distance is #35+3=38# #m#.

The total displacement is #35-3=32# #m# South.