4.37 Calculating Work
4.37 Calculating Work
- Show how to calculate work from force and distance.
- Identify and define the SI unit for work.
- Use the equation for work to find force or distance when the other two variables are known.
Clarissa is cutting the grass in her grandmother’s yard using an old-fashioned push mower. The mower has no motor,
so Clarissa is doing all the work. How much work does Clarissa do pushing the mower around the yard? The amount
of work depends on how much force she uses and how far she pushes the mower.
Work, Force, and Distance
Workis the use of force to move an object. It is directly related to both the force applied to the object and the
distance the object moves. Work can be calculated with this equation:
Work = Force x Distance.
How Much Work?
The equation for work can be used to calculate work if force and distance are known. To use the equation, force
is expressed in Newtons (N), and distance is expressed in meters (m). For example, assume that Clarissa uses 100
Newtons of force to push the mower and that she pushes it for a total of 200 meters as she cuts the grass in her
grandmother’s yard. Then, the amount of work Clarissa does is: