Download Energy: Conservation and Transfer Unit Study Guide • Energy is the

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Energy:ConservationandTransferUnitStudyGuide
Energyistheabilitytodowork,ortobringaboutchange.
Workiswhenaforceappliedtoanobjectactuallymovesthe
object.Withoutmotion,thereisnowork.
Thebasicformsofenergyare:light,heat,sound,electrical,chemical,
andmechanical(energyofmotion)
Therearetwotypesofmechanicalenergy:potentialandkinetic
PotentialEnergy–stored
orbuiltupenergy
KineticEnergy–theenergyofmotion
• Allmatterhassomedegreeofheat.
• Alightbulbproducestwotypesofenergy:lightand
thermal
• Heatistherateofhowfastatomsandmoleculesare
vibrating.Thefasterthevibration,themoreheat.
• Heatalsomeansthetransferofthermalenergyfromone
objecttoanother
Firstlawofthermodynamics:energycannotbecreatednordestroyed.Itcanonlybetransferred.
Thesecondlawofthermodynamics:Heattransferalwaysmovesfromwarmertocolder
Heatandthermalmeanthesamething
Increasingordecreasingthermal(orheat)energycausesmattertochangefromonephaseto
another(solid,liquid,gas)
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Frictionistheresistancethatonesurfaceorobjectencounters
whenmovingoveranothersurfaceorobject
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Frictioncausesheattobuildup.Themorefriction=moreheat
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Electricityflowingthroughanelectricalcircuitproduces
magneticeffectsinthewiresinanelectromagnet
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Inanelectricalcircuitcontainingabattery,abulb,andabell,
energyfromthebatteryistransferredtothebulbandthebell,whichin
turntransfertheenergytotheirsurroundingsaslight,sound,andheat
(thermalenergy).
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Lightcanbereflected,refracted,and
absorbed
Reflection–lightbouncesbackwiththesameamountofenergythatfirsthits
thesurfacesuchasamirror.Imagesappeartolookbackwards.
TheLawofReflection–lightreflectsattheexactsameangleitcamefrom.
Refraction–lightchangesdirectionorbent.Itcausesobjectstolookbent,
broken,larger,orsmaller(telescopeandmicroscope)
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Diffraction–lightissplitintoitssevenseparatecolorsbypassingthroughaprism
Spectrum–thesevencolorsthatmakeupwhitelight(red,orange,yellow,green,blue,indigo,violet)
Absorption–alloftheenergyoflightiscapturedandtransferredtothematterthatcapturesit
Whiteisthecolorthatbestreflectslight.Whensomethingiswhite,itmeansthatallofthecolorsare
reflectedback
Blackisthecolorofabsorption.Whensomethingisblack,itmeansthatallofthecolorshavebeen
absorbed
Ashadowissimplytheresultoflightbeingblockedandabsorbed
Lightspreadsoutfromitssourceinalldirectionsandtravelsinastraightpathunlessitisinterrupted