An object travels North at # 7 m/s# for #6 s# and then travels South at # 3 m/s# for # 8 s#. What are the object's average speed and velocity?

1 Answer
Apr 30, 2016

Answer:

Speed=#33/7m/s#and velocity #=9/7m/s#

Explanation:

Distance traveled due North in 6s @ #7m/s# is =#7xx6=42m#
Distance traveled due South in 8s @ #3m/s# is =#3xx8=24m#
Total Distance traveled #=42m+24m=66m#
Total time taken = #6+8=14s#
So average speed #=(Total Distance )/( time)=66/14m/s=33/7m/s#

Now net displacement due North=#42-24=18m# (North,South being oppositely directed)

Hence Average velocity due North#=(Displacement )/(Time)=18/14m/s=9/7m/s#