1. Conservation of Energy
Chapter 5, Section 3
8th Grade
Mrs. Boguslaw

2. The Law of Conservation of Energy
Energy cannot be created or destroyed
In a closed system, the total amount of energy is always the same
All of the different forms of energy in a sustem always add up to the same total amount of energy

3. Friction Converts mechanical energy into thermal energy
Energy is not “lost” from the system - it is changed into a different form

4. Noise Some mechanical energy is converted into sound energy
Energy is not “lost” from the system - it is changed into a different form

5. If energy is always conserved, why don’t perpetual motion machines actually exist?

6. Thermal Energy
Every time one form of energy is converted into another, some energy is converted into thermal energy
Energy is not “lost” from the system - it is changed into a different form

7. How can we make conversions more efficient?
How can we make more of the form we want to use and less “wasted” energy?

8. Energy Efficiency
A comparison of the amount of energy before a conversion to the amount of USEFUL energy after a conversion
Good way to increase efficiency = reduce friction