1. Kinetic and Potential Energy Examples and Situations

2. Changes in Potential Energy Reminder PE = mgh The amount of potential energy (PE) will increase if the mass (m) or height (h) increases The amount of PE will then decrease as the mass (m) or height (h) decreases

3. Example of changes in potential energy Put the spheres in order of greatest to least amount of potential energy All of the spheres have the same mass B A C

4. Results The order of most to least potential energy is letter B has the most, then C and then A. B A C

5. Changes in Kinetic Energy Reminder the formula for kinetic energy is KE = ½ mv 2 Reminder that kinetic energy is the energy of motion This type of energy is affected by mass and velocity

6. Changes in Kinetic Energy Put the three spheres in order of greatest to least kinetic energy All three spheres have the same mass B A C

7. Results The order of greatest to least kinetic energy is letter A has the most, then letter C and the least is letter B B A C

8. Law of Conservation of Energy The law of conservation of energy states that energy is never created or destroyed Energy is converted or changed from one form to another

9. Specific Heat Specific heat is the amount of heat needed to raise the temperature of one gram of a material by one degree Celsius The more mass an object has the more particles of matter it contains so it can absorb more heat energy The world’s oceans absorb lots of heat during the summer and releases it during the winter which keeps coastal climates moderate

10. Specific Heat continued The lower a material’s specific heat is, the more its temperature will rise when a given amount of energy is absorbed by a given mass For example, if equal masses of iron and plastic absorb the same heat, the iron’s temperature will rise more, since iron has a lower specific heat than plastic