Ch.9, Sec.2 – Energy Conversions energy conversion: the change of one form of energy to another Examples of Kinetic & Potential Energy: 1. Skate Boarder = potential energy (PE) at the top to kinetic energy (KE) going down and back to potential energy (PE) at the top of the half-pipe 2. Model Airplane = the wound rubber band has elastic potential energy (PE) changed to kinetic energy (KE) when it is released

Ch.9, Sec.2 – Energy Conversions Conversions Involving Chemical Energy: 1. Chemical energy (CE) comes from food to help us function 2. Light (LE) used by plants in photosynthesis to make sugars (CE) 3. Conversions when you eat food: light energy (LE)--> chemical energy (CE)-->kinetic energy (KE) 4. Conversions in a campfire: light energy (LE)-->chemical energy (CE)-->thermal energy

Ch.9, Sec.2 – Energy Conversions Why Energy Conversions Are Important 1. Conversions are needed for everything we do 2. Machines help us make energy conversions 3. Electrical energy can be converted into light, sound, thermal, or kinetic energy! Energy & Machines 1. A machine changes the size and the direction of a force 2. Machines convert energy from one form to another 3. Energy conversions in a bicycle = chemical energy (CE) to kinetic energy (KE)

Ch.9, Sec.2 – Energy Conversions 4. Bicycles seem easier to ride when kinetic energy (KE) is transferred to the pedals, to gears, to chain and back to the wheel 5. Radiometer turns = light energy (LE) to thermal energy (TE) to kinetic energy (KE)

Ch.9, Sec.2 – Energy Conversions Use your textbook (pgs. 248 – 253) to help you find all of the energy conversions for each example listed below: skateboarder – _______________________________ model airplane – ______________________________ soccer player – _______________________________ hair dryer – __________________________________ bicycle – ____________________________________ radiometer – _________________________________