Today we are going to learn about Kinetic and Potential energy.

Ability to do work (change) What is energy? Ability to do work (change)

Remember the forms of energy! Thermal Energy – motion of energy in the particles of matter due to more/less heat. (Heat energy = when thermal energy is transferred) Radiant Energy – electromagnetic waves of light (Solar Energy = specifically from the Sun) Chemical Energy – energy stored in matter Electrical Energy – energy flowing in an electric circuit. Mechanical Energy – due to motion and position Potential Energy – stored energy Kinetic Energy – moving energy

Types: - Chemical Types: Thermal - Heat Solar Electrical Radiant

Potential Energy - Is stored energy = not in use - Can’t see it, but it is there. - Based on position/height or composition (inside materials) It is called potential energy because it has the potential to be converted into other forms of energy, such as kinetic energy. Use foldable to write notes in journal

Potential Energy Examples: 1. Wound-Up Spring 2.Baseball Pitcher (not released yet) 3. Holding a hammer high.

The higher the object = the more the potential energy High PE Low PE Almost every object has the potential to do work, or store energy, but the objects original position needs to be altered so it can eventually move. For example: If the Yo-Yo we used in example one was just sitting of a table, it doesn’t have potential energy because the object by itself doesn’t have the capability to do work or move. If you pick the Yo-Yo up off the table, it now has altered its original position, and can store energy because it can now work with your help. What letter will the cart have the most PE?

The more mass an object has= the more the potential energy vs. vs. Almost every object has the potential to do work, or store energy, but the objects original position needs to be altered so it can eventually move. For example: If the Yo-Yo we used in example one was just sitting of a table, it doesn’t have potential energy because the object by itself doesn’t have the capability to do work or move. If you pick the Yo-Yo up off the table, it now has altered its original position, and can store energy because it can now work with your help. vs.

More Examples of (Position) Potential Energy: 4. Stretching a rubber band.. -Stores energy Water at the top of a waterfall.. -Stores energy Yo–Yo held in your hand.. -Stores energy because of position Some examples of potential energy are.. Stretching a rubber band… this store energy because it has the ability of doing work. Water at the stop of the fall has the ability of falling, therefore it stores energy. A Yo Yo held in your hand stores energy because when you alter its position it now has the ability of doing work. A bow and arrow has stored energy because its position has changed and it now has the capability of shooting the arrow. Drawing a Bow… -Stores energy because of position

Chemical Energy is a type of Potential Energy Energy is stored in bonds of chemicals that make up the substance. Energy can be released, but hasn’t been yet.

Chemical Examples: FUELS: Wood Coal Oil Gas *Energy is stored until they are burned. Items that have stored energy.

Chemical Examples: Food Batteries Candle wick Items that have stored energy.

Kinetic Energy Is based on movement. Can see it. The second form of energy is Kinetic energy. This is calculated by ½ of the object’s mass multiplied by double the object’s speed.

Examples of Kinetic Energy Running Wood Burning Rock Falling

More Examples of Kinetic Energy Shooting a rubber band. Water falling over the fall. A Yo-Yo in motion. Releasing the arrow from the bow. Using the same examples as potential energy, you can see how the same object that previously had PE now has KE. If the rubber band we were stretching to give it PE, were to be let go, it would now have KE because its now in motion. Same with the water in the waterfall, when it falls over, its now in motion. The Yo-Yo and the arrow from the bow are also moving, giving all these objects KE.

Types of Kinetic Energy Thermal/Heat – particles in matter move as heat is added. Radiant/Solar – electromagnetic waves move through space to Earth Electrical – electrons move through metal in a closed circuit to provide power to objects.

Energy doesn’t always stay in one form…it TRANSFORMS Occurs between various types of energy. Energy is never lost. 1 energy form can transform into 2 different forms.

Law of Conservation of Energy “Energy can neither be created nor destroyed, it just changes forms.” This means that no energy is ever “lost”! Energy is just transformed. Total amount of energy in = total energy out

Potential Energy Converted to Kinetic Energy… When stored energy begins to move, the object now transfers from potential energy into kinetic energy. Potential energy eventually will need to transfer from it’s stored energy into motion. If a person is standing still, they obtain potential energy because the have the ability to walk or run… if the same person who is standing still decides to start running, then they have transferred their PE into KE… in other words, they went from storing energy, to moving energy.

Energy Transformation with Food Potential Energy: When you look at your food and eat it because it has the potential to give you energy Kinetic Energy: When you digest your food into usable energy the chemicals in the food are set into motion

Examples of transformations of Potential to Kinetic Water behind a dam > water falling down.

Examples of transformations of Potential to Kinetic Book on high shelf> book falling down.

Examples of transformations of Kinetic to Potential Water moving down a river > water stopping at a closed dam.

Examples of transformations of Kinetic to Potential Moving book up to a shelf > book sitting on a high shelf.

Name the transformations…

Don’t forget about friction… Friction generates heat This means… Not all potential energy is converted to kinetic….some is also transformed to thermal energy. This makes objects stop and transform back to potential.

Energy Lesson Review Energy is the ability to do work. All forms of energy fall under 2 categories: Kinetic or Potential Potential = stored Kinetic = moving Energy cannot be created or destroyed. Energy is always being transformed.