MIMTY 4/09/10 Why does it take energy to pick something up and stick it in a high place? MIMTY

Kinetic and Potential Energy We’re going to start class by finding the difference between potential and kinetic energy. For the next 10 minutes, find the definition for both in any way you can.

Vocabulary Kinetic Energy Potential Energy Energy of things in motion. Energy stored up from gravity. The higher up something is, the more potential energy it can release. vocab

Equation Kinetic Energy E: KE = ½ m v 2 V: KE: kinetic energy (in Joules) m: mass (in kilograms) v: velocity (in meters/second) S: Tells us the energy of something that is moving equation

Equation Potential Energy E: PE = m g h V: PE: potential energy (in Joules) m: mass (in kg) g: gravity (9.8 m/s 2 ) h: height (in meters) S: Tells us how much energy something could have if it were to fall down.

Kinetic and Potential Energy Time to practice. You likely saw all this back in middle school, but we need to cover it to get to a few very important concepts. Work on problems 1 through 6 for the next 20 minutes. classwork

Conservation of Energy What it means Energy never runs out. It just moves around. *A chair sits on the ground with little energy. notes

Conservation of Energy What it means Energy never runs out. It just moves around. *A chair sits on the ground with little energy. *I pick it up and I lose energy while the chair gains potential energy.

Conservation of Energy What it means Energy never runs out. It just moves around. *A chair sits on the ground with little energy. *I pick it up and I lose energy while the chair gains potential energy. *The chair sits up high with lots of potential energy.

Conservation of Energy What it means Energy never runs out. It just moves around. *A chair sits on the ground with little energy. *I pick it up and I lose energy while the chair gains potential energy. *The chair sits up high with lots of potential energy. *The chair falls and the energy turns into kinetic.

Conservation of Energy What it means Energy never runs out. It just moves around. *A chair sits on the ground with little energy. *I pick it up and I lose energy while the chair gains potential energy. *The chair sits up high with lots of potential energy. *The chair falls and the energy turns into kinetic. *The chair hits the ground and that energy turns into sound.

Conservation of Energy How we can use this If we look at an object and add together its KE and PE, the total will always be the same, no matter what that object is doing.

Conservation of Energy Example A ball rolling down a slope. We take pictures at 3 different points in time. A, B, and C. Ball weighs 1 kg. Slope is 1 meter high. A B C

Conservation of Energy Example A ball rolling down a slope. We take pictures at 3 different points in time. A, B, and C. Ball weighs 1 kg. Slope is 1 meter high. A B C KE = 0. Not rolling yet PE = 10 J

Conservation of Energy Example A ball rolling down a slope. We take pictures at 3 different points in time. A, B, and C. Ball weighs 1 kg. Slope is 1 meter high. A B C KE = 0. Not rolling yet PE = 10 J KE = 10 J. Fast! PE = 0. No height!

Conservation of Energy Example A ball rolling down a slope. We take pictures at 3 different points in time. A, B, and C. Ball weighs 1 kg. Slope is 1 meter high. A B C KE = 0. Not rolling yet PE = 10 J KE = 10 J. Fast! PE = 0. No height! KE = 5 J PE = 5 J

Conservation of Energy Example A ball rolling down a slope. We take pictures at 3 different points in time. A, B, and C. Ball weighs 1 kg. Slope is 1 meter high. At all points A, B, and C, KE + PE = 10. For this example, it always adds to 10. A B C KE = 0. Not rolling yet PE = 10 J KE = 10 J. Fast! PE = 0. No height! KE = 5 J PE = 5 J

Conservation of Energy Your job for the rest of class is to finish the worksheet. Once completed, turn this worksheet in. classwork

Exit Question When have you experienced the most potential energy ever?