An object travels North at #8 m/s# for #2 s# and then travels South at #3 m/s# for #4 s#. What are the object's average speed and velocity?

1 Answer
Mar 14, 2018

Answer:

Average speed = 4.67 m/s
Average velocity = 0.67 m/s N

Explanation:

Speed, a scalar measurement, is how fast an object moves over a surface; velocity, a vector quantity, is how fast and in what direction.

Speed
= #8m/s +8m/s+3m/s+3m/s+3m/s+3m/s=28m/s# over 6s

Average speed = #28/6=4.667 m/s#

Velocity is how far an object is displaced from its starting point over a period of time.

The object moved 8m/s North x 2s = 16 m North, then 3m/s South x 4s = 12 m South, for a total displacement of 4 m North over 6 seconds.

Average velocity #= ((4m) N)/(6s)=0.67 m/s N#