Modified: September 04, 2007
Welcome
Syllabus
Calendar
Sample Problems
Term Project
Introduction
Chapter 1
Chapter 2
Chapter 3
Chapter 4 >
Chapter 5
Chapter 6
Chapter 7
Chapter 8
Chapter 9
Chapter 13
Chapter 14
Chapter 15
Work, Power, & Energy

Objectives:

  • Define:
    • Mechanical Work
    • Energy
    • Kinetic Energy
    • Gravitational Potential Energy
    • Strain Energy
    • Power
  • Distinguish the differences between positive and negative work
  • Explain the relationship between mechanical work and energy

Slides that summarize the information presented in class, regarding Chapter 4.

 

Chapter Summary

  1. Mechanical work (U) is a quantity that describes the extent to which a force can move an object.
  2. Energy (E) is the ability to perform work; performance of work requires an expenditure of energy (U = ΔE).
  3. In human motion analysis, we are primarily concerned with kinetic energy (KE = 1/2·m·v2), and energy related to the position of an object: gravitational (GE = m·g·h) and strain                   (SE = 1/2·k·x2).
  4. Power is the rate of change of work; it is the amount of work that can be performed in a certain amount of time.