Understanding Concepts Work and Energy Review Understanding Concepts

Work Done by a Constant Force Recall that where work is measured in joules (J) So, what is work really?

Now, lets put this all together…. Work Cont’d As the equation suggests, work is simply how much force is being applied to an object over a given displacement. But why is this important? Recall that an applied force is simply a measure of how much each unit of mass is being accelerated. Also, an accelerated object must experience a change to its momentum (Inertia). Now, lets put this all together….

Work-Energy THM So, as we just saw, work and energy are one and the same thing. However, more accurately described, we say that: Energy is an objects ability to do work In terms of Kinetic Energy and Work: or

Where the direction of the force is opposite that of the displacement. Work due to Friction Another common form of work done, one you haven’t discussed thus far, is the work done due to friction. Mathematically, this is defined as: Where the direction of the force is opposite that of the displacement.