Forces and Newton's Law
Conservation of Energy
Conservation of Momentum
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Classic Problem in Conservation of Energy
Here is an example of a typical question in the area of Conservation of Energy that students have difficulty solving:
Car, starting at rest, driving down a hill
In order to solve this problem we must find out the final speed of the car at the bottom of the hill right before it stops. We can do this by applying the law of conservation of energy, which states that the sum of initial kinetic and potential energies is equal sum of the final kinetic and potential energies. The following formula is used for conservation of energy:
After writing the formula we can plug in the information that is stated in the problem. The easiest way to do so is to plug the data into each part of the formula separately and try to simplify it.
In this problem we are given the following:
Plug the data into the formula:
We are going to cancel masses because they are the same on both sides of equation:
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