Energy What is energy? ENERGY is the ability to cause change. There are many different kinds of energy. Everything around us has energy YOU have a large amount of energy. When change occurs, energy is transferred from
one object to another. Footsteps transfer energy from foot to ground to ears. Warmth is felt when the sunlight transfers energy to a table or chair. Where do you see energy? Energy of Motion KINETIC ENERGY is the energy an object has due to its motion.
KE = x mass x (velocity)2 The faster something is moving, the more kinetic energy it has. The heavier a moving object is, the more kinetic energy it has. Which one has greater KE? Two vehicles, a semi and a VW beetle, traveling at 60 mph each
A snowball thrown or a cannonball fired A bullet fired or a bowling ball rolled down a lane Energy of Position POTENTIAL ENERGY is the energy an object has based on its position.
PE = mass * gravity * height Objects very high up have lots of potential energy. Which picture has greater PE? YOU R
-O Total Energy The TOTAL ENERGY is the combination of kinetic and potential energy of a system. TE = KE + PE The LAW OF CONSERVATION OF ENERGY states that energy can neither be created nor destroyed it only changes forms.
Practice! https:// www.youtube.com/watch?v=izVeVfcfSws Where is Higginss potential energy the greatest? What happens to his kinetic energy as he rolls down the hill?
Draw a picture of what Higginss path might have looked like. What happens to Higginss potential energy as he rolls down the hill? What happens to his total energy? At the very end, where does all the energy from his motion go?
Phet demonstration We are going to look at an online demonstration, and decide where potential and kinetic energy are the highest. What is happening as the skateboarder goes up/down the hill? What is happening to their total energy? What happens if we change the ramp?
INTRO Using the U-shaped track, examine the motion of the skater. Is energy conserved? Where is KE, PE the highest? Click on Bar graph
Notice where the skaters speed is the highest Click on Speed How does this relate to KE? PE? Notice where the skaters height is the highest Click on Grid How does this relate to KE? PE? Friction Using the U-shaped track, examine
the motion of the skater. Is energy conserved? If you leave the skater alone, what eventually happens? Click on Speed Where does this energy go? Click on Bar graph
Activity! Human Continuum During this activity, you will be asked to stand in an area of the room that represents your answer to a question. You may be asked to defend your answer be ready to give your reasoning! A skater starts at the top of a ramp. Is his energy:
Potential? Kinetic? Thermal? A skater is at the bottom of the ramp, quickly moving up to the other side. His energy is: Kinetic, potential, or a mix? Where is this skater on the ramp,
given his energy? Top (moving up) Bottom Middle Top (moving down) Same question where is this skater?
Top Middle Bottom Top Middle Bottom
In which position does the skater have the most? Kinetic energy Potential energy Total energy E A
C D B At the highest point kinetic energy is zero / maximum while the potential energy is zero / maximum. At the lowest point kinetic energy is zero / maximum while potential
energy is zero / maximum. Mass affects / does not affect the amount of energy. As an object falls in gravity, kinetic energy increases / decreases / remains the same. As an object falls in gravity, potential energy increases / decreases /
remains the same. As an object falls in gravity, total energy increases / decreases / remains the same. An object travelling faster and faster has a kinetic energy that increases / decreases / remains the same. An object travelling faster and faster has a
potential energy that increases / decreases / remains the same. As an object speeds up, the total energy increases / decreases / remains the same. As an object slows down, the total energy increases / decreases / remains the same.
