Unit 3: Work and Energy

     Although the Greek term "energeia" was used by Aristotle 2500 years ago, the current scientific use of the English word "energy" had its origin in the early 1800's.  When forces are applied to objects and the objects displace, energy has been added to or removed from the system.  Because the terms associated with energy have usage beyond physics (such as work and power) it's important to gain a solid understanding of how they are operationally used in physics...so let's "get to work" by clicking on the introduction to this topic in the workflow at the left.

Suggested timeframe: 2 weeks

Big Ideas:
1. A system has energy if it has the ability to perform work.
2. Work occurs when an object is displaced by a force.
3. The potential energy of a system is associated with the arrangements of particles in that system and is measured relative to a frame of reference while the kinetic energy of an object in the system is based on its motion relative to some frame of reference.
4. The total mechanical energy of a system is the combination of its potential and kinetic energies and is unchanged if only conservative forces act on the system.
5. Power is the rate at which energy is used.