Work :

Objectives:

   1.    Define work in terms of force and distance.

   2.    Explain the units of force and work.

   3.    Calculate work, force, and distance using the formula W = F x d.

Key Terms:

    work    joule

Web Resources:

    http://www.glenbrook.k12.il.us/gbssci/phys/Class/energy/energtoc.html

Notes:

Work:

The amount of force times the a time interval is equal to the impulse of an object.  The distance that the object moves times the force is work.  Both are related but different.  Work is a force acting through a distance. These two conditions must be present in order for there to be a force.

There MUST be a net FORCE.

The force MUST make the object MOVE in the direction of the force.


What does this mean?

            If I push against the wall with all of my might, am I doing work?  NO.

            If I carry a heavy weight across the room, am I doing work?  NO.

It is important to remember that work does not involve time. Work ONLY involves the application of force and the movement of an object in the direction of the force.

            Formula:    Work = F * D                Unit:    Joule (1N*m)

For work done in a vertical direction you can use the alternative equation.

             Work = mgh   (mass x gravity x height)