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3: Work and Energy

Last updated

Nov 8, 2022
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- Sample Problems
- 3.1: The Work - Energy Theorem

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3.1: The Work - Energy Theorem
For a large number of applications in mechanics, we are not interested in how a force causes the direction of motion of an object to change – we only care about how that force changes the speed of the object.
3.2: Work and Energy for Collections of Particles
We discover that a system comprised of a collection of many moving particles can be reimagined as a single system that has both a collective kinetic energy and an internal energy.
3.3: Conservative and Non-Conservative Forces
We categorize forces according to the dependence of the work they perform on the path that the effected particles follow.
3.4: Energy Accounting with Conservative Forces: Potential Energy
We introduce a useful shortcut to avoid complicated work calculations for conservative forces.
3.5: Energy Accounting with Non-Conservative Forces: Thermal Energy
We now put together what we have learned about energy to give us a powerful toolbox for solving problems in the macroscopic world.
3.6: Mechanical Advantage and Power
We will now take a closer look at simple machines from the perspective of work-energy, and discuss the rate at which work is performed.
3.7: Energy Diagrams
An energy diagram provides us a means to assess features of physical systems at a glance. We will examine a couple of simple examples, and then show how it can be used for more advanced cases in physics and chemistry. It's important to understand that there is no new physics in here – what we have learned so far now is simply represented diagrammatically, making it easier in some cases to see the "big picture" of a physical system.
Sample Problems

Image used with permission (CC BY-SA-NC; anonymous).

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