Creative Commons License Copyright © Michael Richmond. This work is licensed under a Creative Commons License.

Physics 211, Quiz 15

Joe drives a racecar around a circular track of radius R = 700 m with a constant speed of 40 m/s.

Question 1:

Is Joe's velocity v constant?

  Answer: no, velocity is a vector quantity.  Since the direction
          of Joe's velocity is constantly changing, 
          his velocity is also constantly changing (even though
          the magnitude of his velocity is always the same).

Question 2:

Is Joe's acceleration a constant?

  Answer: no, acceleration is a vector quantity.  Since the
          direction of Joe's acceleration is constantly 
          changing, his acceleration is constantly changing --
          even though the magnitude of his acceleration is 
          always the same:

                                           (40 m/s)^2
             magnitude of acceleration =  ------------- = 2.3 m/s^2
                                             700 m 

Creative Commons License Copyright © Michael Richmond. This work is licensed under a Creative Commons License.