Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Work is scalar

  1. Mar 27, 2010 #1
    hello people ,

    We know that work done is scalar because it’s the product of two vector quantities so it needs only magnitude to be defined.
    But look …W = Fd cos theta
    When the acting force is in the opposite direction to displacement then theta=180

    Therefore the work done becomes negative in this case so work is affected by the directions and its scalar so how?
     
  2. jcsd
  3. Mar 27, 2010 #2
    Would you like to draw a sketch of a force with its point of application being moved 180 to its line of action?

    You should see the answer immediately.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook