The Man’s PSSA Practice Forces acting on the parachutist? Choice B- Friction & Gravity Incorrect Answer Choices: Choice A- Momentum is not a force Choice C- Inertia and momentum are not forces Choice D- Kinetic and potential are energies Best example of potential energy? Choice B- Stretched rubber band (elastic potential) Incorrect Answer Choices: Choice A- Wind turbine (Wind & kinetic energies) Choice C- Fire (light and heat) Choice D- Sunlight (light and heat) KE and PE of the boulder before the earthquake and after… Before the boulder rolls down the hill- lots of potential energy (high height off of the ground) but no kinetic energy (no movement). As the boulder rolls, it gains kinetic energy while losing potential energy (b/c it’s closer to the ground- lower PE and moving fasterhigher KE) Rolling boulder (relationship between kinetic and potential energy)… Potential energy is transformed into kinetic energy. Explain why student B has more potential energy than Student A. Student B is higher off of the ground (greater height) Student A dives from the board into the water. Why does student A’s kinetic energy decrease as the student enters the water? The student’s velocity decreases (the student is slowing down) At which position does the boulder have the greatest kinetic energy Choice 2- B (at the bottom of the hill it is moving the FASTEST) As it moves from location A to location D in the diagram, the energy stored in the coal (4) Is transformed Which statement best describes the energy changes that occur while a child is riding on a sled down a steep, snow-covered hill? (2) Kinetic energy increases and potential energy decreases (b/c the sled is moving faster- more kinetic energy as it goes down the hill and is closer to the groundlower potential energy)