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work and energy

13 videos
4A: Work doesn’t always have to break your back. In physics, it has a different meaning. When a force is applied to an object and results in displacement, work has been done. When an apple falls from a tree, gravity has done work on the object as it descends earthward. And as work is done by gravity on the object, its gravitational potential energy is converted into kinetic energy (which is also why it hurts as it lands on your head, hopefully resulting in a brilliant Newtonian idea). Let’s get moving!

Introduction to work and energy

VIDEO 9:18 minutes
Introduction to work and energy

Work and energy (part 2)

VIDEO 9:51 minutes
More on work. Introduction to Kinetic and Potential Energies.

Work example problems

VIDEO 4:50 minutes

Conservation of energy

VIDEO 10:06 minutes
Using the law of conservation of energy to see how potential energy is converted into kinetic energy

Work/energy problem with friction

VIDEO 10:05 minutes
A conservation of energy problem where all of the energy is not conserved.

Intro to springs and Hooke's law

VIDEO 10:05 minutes
Introduction to Hooke's Law

Potential energy stored in a spring

VIDEO 10:00 minutes
Work needed to compress a spring is the same thing as the potential energy stored in the compressed spring.

Spring potential energy example (mistake in math)

VIDEO 9:38 minutes
A spring, a frozen loop-d-loop and more! (See if you can find the mistake I made and get the right answer!)

Conservative forces

VIDEO 4:02 minutes

Power

VIDEO 5:46 minutes

Introduction to mechanical advantage

VIDEO 10:02 minutes
Introduction to simple machines, mechanical advantage and moments.