2. Law of Conservation of Energy
How do I solve problems utilizing the Law of Conservation of Energy?
3. Other forms of Energy
So far we have only talked about Mechanical Energy
Other forms of energy:
Electrical
Nuclear
Thermal
Chemical
Even with these forms of energy, work is done when the energy is
transferred from on object to another
4. Conservation
Adding up all forms of energy
Total Energy stays the same
Energy as a whole is conserved
5. Accounting for Nonconservative Forces
While pushing something along a rough surface and friction occurs, what
happens?
What happens to the kinetic and potential energies?
Some of the energy is converted to …..?
Total Energy stays the same
7. Problem Solving Steps
1. Draw a picture.
2. Determine the system for which energy will be conserved.
3. Figure out what you are looking for, and decide on the initial and final
positions.
4. Choose a logical reference frame.
5. Apply conservation of energy.
6. Solve.
8. Example
The roller coaster car reaches a
height of 25 m on the second hill
before coming to a momentary
stop. It traveled a total distance of
400 m. Estimate the average
frictional force on the car, whose
mass is 1000 kg.
Step 1: Draw a picture
Step 2: Define the system (what
forces are acting on it?)
