The Physics Classroom » Calculator Pad » Work, Energy, and Power » Audio Help » Set WE1, Q4

Mechanics: Work and Energy

Work and Energy: Audio Guided Solution

Problem Set WE1, Question 4:

Lester in the PE Department is pushing an 88.4-kg load of towels at constant speed a distance of 22.9 m using a horizontal force of 152 N. Determine the work done by friction. Enter the appropriate + or – sign.

 
 

 

 




 

Audio Guided Solution

Click to show or hide the answer!




Habits of an Effective Problem Solver

  • Read the problem carefully and develop a mental picture of the physical situation. If necessary, sketch a simple diagram of the physical situation to help you visualize it.
  • Identify the known and unknown quantities in an organized manner. Equate given values to the symbols used to represent the corresponding quantity - e.g., vo = 0 m/s; a = 4.2 m/s/s; vf = 22.9 m/s; d = ???.
  • Use physics formulas and conceptual reasoning to plot a strategy for solving for the unknown quantity.
  • Identify the appropriate formula(s) to use.
  • Perform substitutions and algebraic manipulations in order to solve for the unknown quantity.



​

Read About It!

Get more information on the topic of Work, Energy and Power at The Physics Classroom Tutorial.



 

Watch It!

Try our YouTube videos on the topic of ...