Giancoli 7th Edition textbook cover
Giancoli's Physics: Principles with Applications, 7th Edition
Describing Motion: Kinematics in One Dimension
Change chapter

2-1 to 2-3: Speed and Velocity
2-4: Acceleration
2-5 and 2-6: Motion at Constant Acceleration
2-7: Freely Falling Objects
2-8: Graphical Analysis

Question by Giancoli, Douglas C., Physics: Principles with Applications, 7th Ed., ©2014, Reprinted by permission of Pearson Education Inc., New York.
Problem 9

A person jogs eight complete laps around a 400-m track in a total time of 14.5 min. Calculate

  1. the average speed and
  2. the average velocity, in m/s.
  1. 3.68 m/s3.68\textrm{ m/s}
  2. Zero!
Giancoli 7th Edition, Chapter 2, Problem 9 solution video poster

In order to watch this solution you need to have a subscription.


This is Giancoli Answers with Mr. Dychko. The average speed is the total distance traveled divided by the total time. So the runner goes eight laps for every 14.5 minutes and we'll convert the laps into meters by multiplying by 400 meters per lap and so the laps cancel leaving us with meters and then times by 1 minute for every 60 seconds making the minutes cancel and we are left with seconds in the bottom; this gives an average speed of 3.68 meters per second. The average velocity is zero because the runner has no displacement; they end up at the same position that they started at so zero average velocity.

Find us on:

Facebook iconTrustpilot icon
Giancoli Answers, including solutions and videos, is copyright © 2009-2024 Shaun Dychko, Vancouver, BC, Canada. Giancoli Answers is not affiliated with the textbook publisher. Book covers, titles, and author names appear for reference purposes only and are the property of their respective owners. Giancoli Answers is your best source for the 7th and 6th edition Giancoli physics solutions.