Energy TransformationsEnergy Transformations

Chapter 5Chapter 5

Energy ConversionsEnergy Conversions=the transfer of energy from one form to =the transfer of energy from one form to anotheranother

-energy is -energy is constantlyconstantly being changed from being changed from one form to another!one form to another!

What is What is EnergyEnergy??

=the ability to do work=the ability to do work

-it can cause changes in temperature, -it can cause changes in temperature, shape, speed, or direction of an objectshape, speed, or direction of an object

Types/Forms of EnergyTypes/Forms of EnergyPotential energyPotential energy: : stored energy that stored energy that can be converted can be converted into other formsinto other forms

Kinetic EnergyKinetic Energy: is : is the energy due to the energy due to motionmotion

Solar EnergySolar Energy: energy : energy from the sunfrom the sun– Key to life on earth: Key to life on earth:

plants use the sun to plants use the sun to create glucose in which create glucose in which we use to breakdown we use to breakdown for energyfor energy

Thermal EnergyThermal Energy::Energy created by heat

Wind Energy: kinetic energy captured by windmills

Geothermal energy: Geothermal energy: heat produced within heat produced within the Earth can be used the Earth can be used for heat or converted to for heat or converted to other formsother forms

Understanding Energy ConversionsUnderstanding Energy ConversionsThere are 3 main There are 3 main components to any components to any energy conversion energy conversion system:system:– 1) 1) Input energy:Input energy:

energy that first enters energy that first enters the systemthe system

– 2) Energy is changed 2) Energy is changed from one form to from one form to another by a another by a converterconverter

– 3) Energy leaves the 3) Energy leaves the system as the system as the output output energyenergy

What is the input energy?

What is the converter?

What is the output energy?

Another example….Another example….A person running (a chemical A person running (a chemical conversion):conversion):

Input: potential chemical energy (glucose/food)

Converter: mitochondrion in cells breakdown glucose to produce chemical energy for muscles

Output: The hurdler runs and jumps (kinetic energy), also thermal energy is produced (that’s why you sweat)

Law of Conservation of EnergyLaw of Conservation of Energy=Energy cannot be created or destroyed =Energy cannot be created or destroyed but can only be changed from one form or but can only be changed from one form or energy to anotherenergy to anotherInput Energy = Output Energy

ororInput Energy = useful Output Energy + waste Output Energy

-Some common waste energy are: sound, heat, light-Some common waste energy are: sound, heat, light

-Ex. Think of a car, what is the useful output -Ex. Think of a car, what is the useful output energy? What is the wasteful output energy?energy? What is the wasteful output energy?