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inpointform
Displayofresults:
-table-graph
Results:
Errorsintheexperimentandwaystoimprovetogetaccurateresults:
PLO-Equationofmotion-uniformingacceleratedobject.
1)Vf=Vo+at
2)a=(Vf-Vo)/t
3)d=Vot+1/2×
at2
4)d=(Vf+Vo)/2×
t
5)Vf2=Vo2+2ad
Vf=finalvelocitym/sa=accelerationm/s2t=times
Vo=initialvelocitym/sd=displacement
PLO-Definitioninmotionandgraph
PLO-Projectiles
-projectilesareobjectswhicharefiredintotheair
-theirmotionobeyskinematicequationscompletelyifweignoreairresistance
-objectslaunchedwithahorizontalvelocityanddroppedformthesameheightwillalwaysstrikethegroundatthesametime.
-thetimeprojectilespendsintheairdependsuponitsinitialvelocityandverticalaccelerationonly.
Thehorizontal:
dx=Vot+1/2×
Thevertical:
dy=-1/2×
gt2
Dynamics
Differentbetweenkinematicanddynamics:
kinematicsdescribehowanobjectmoves;
dynamicsdescribewhyitmoves.
Force:
pushorpullexertedbyanobjectontheother.
Unitofforce:
Newton(N)1Newton=1kgm/s2
Typesofforces:
-frictionalforce(necessaryevil)
-gravitationalfore(existeverywhere)
-electricforce
-Magneticforce
-airresistance
-centrifugalforce
-centripetalforce
-normalforce(FN):
actsperpendiculartothesurfaceonwhichtheobjectisplaced.
PLO-Newton'
slawofmotion:
Newton'
sfirstlaw(lawofinertia)
Whennoexternal,unbalancedforceactsonanobjects,itsvelocityremainconstant.
Ifnonetforceactsonanobject,itmaintainsitsstateofrestoritsconstantspeedinastraightline.
ssecondlaw:
Whenanexternal,unbalancedforceactsonanobject,theobjectaccelerates.Theaccelerationsisinthesamedirectionasthenetforceactingontheobject.
Theaccelerationvariesdirectlywiththenetforceapplied.
Theaccelerationvariesinverselywiththemassoftheobject.
Fnet=ma
sthirdlaw:
Foreveryactionthereisanequalandoppositereaction.
Actionandreactionalwaysoccurinpairs.
F1=-F2
slawofuniversalgravitation
Statethe:
a)thegravitationalforceisdirectlyproportionaltotheproductoftheirmasses:
Fg∝m1m2
b)Thegravitationalforceisinverselyproportionaltothesquareofthedistancebetweenthecentreoftheobjects.
Fg∝1/r2
Fg∝m1m2/r2
Fg=Gm1m2/r2
G=universalgravitationalconstant=×
10-11kg2→measuredbyCavemdishusingatorsionbalance
*massoftheearth=×
1024kg
Radiusoftheearth=×
106m
TheFrictionalforce:
Actsintheoppositedirectiontothemovementoftheobject.It'
srepresentedbyFf.
Thefrictionalforcedependson:
I)thenormalforce
II)thenatureofthesurface→coefficientoffriction→denotedbyμ(mu)
Ff=μFN
Energy
Elastic--abletostretchandreturntoitsoriginalsizeandshape
Elasticpotentialenergy--energypossessedbyanelasticobject.
Extension--extendedlength-originallength
Conservation--momentumdoesn'
tchange
Momentum--p=mv
Mechanicalenergy--Theenergyacquiredbytheobjectsuponwhichworkisdoneisknownasmechanicalsumofand
Energy--thecapacitytodowork
Potentialenergy--(storedenergy)=mgh
Kineticenergy--energypossessedbyamovingobject.=1/2(mv2)
Work--W=F×
d
Power--istherateatwhichworkisdoneorenergytransformed.(workdone)/(time)&
(energychanged)/(time)
Efficiency=(workoutput)/(workinput)×
100%
Workinput:
worksuppliedintothesystem
Workoutput:
usefulworkdone
Conservationofenergy:
Lawofconservationofenergy--energycaneitherbecreatedordestroyedbutonlytransformedfromaformtoanother.
Hooke'
slaw:
Theforceappliedisdirectlyproportionaltotheextension.
F=kx
F=forceapplied,x=extension;
k=forceconstant
*breakingpoint:
pointtowhichtheobjectexceedsitselasticlimit.
Momentum:
-conceptofmomentum
-Impulseandmomentum
-Collisionsandexplosions
-Elasticandinelasticcollision
Ft=p=m△v
Conservationofmomentum:
-notchangingconservedduringcollisions.
-"
headon"
InlinearInteraction:
1)elastic--objectcollideandmoveawayfromeachother
Beforecollision:
Totalmomentum=m1v1+m2v2
Aftercollision:
Totalmomentum=m1v1'
+m2v2'
2)Inelastic--objectscollide,sticktogetherandtravelatacommonvelocity.
Totalmomentum=(m1+m2)V'
Lawofconservationofmomentum:
totalmomentumbeforecollision=totalmomentumaftercollision
Mechanicalenergy
Mechanicalenergycanbeeitherkineticenergyorpotentialenergy:
Totalmechanicalenergy=potentialenergy+kineticenergy
LossinPE=gaininKE→lawofconservationofmechanicalenergy
ME=mgh+1/2(mv2)
power
Poweristherateatwhichworkisdoneorenergytransformed.
Power=(workdone)/(time)&
(energychanged)/(time)(J/s)
Power=Force×
velocityP=FV
SIunitofpowerisWatt(W)
P=I2RP=V2/RP=IV
Work
A.Energyisdefinedastheabilitytodowork.
B.Work=force×
displacement
C.Workismeasuredinwhichisalsocalledajoule(J)
D.Althoughworkisaproductoftwovectorquantities,itisascalarquantity.
E.Whentheforceisnotinthesamedirectionasthedisplacement,mustusethecomponentoftheforcethatisinthedirectionofthedisplacement.
PLO-waves:
characteristics
Vocabulary:
Pulse-asingledisturbancemovingthroughamediumfromonelocationtoanotherlocation.
Wave-asinglepulsewithacrestandatrough.
Crest-upperpartofthewave.
Trough-lowerportionofthewave
Wavemotion-seriesofwaves
Rarefactions-airparticlesarefarapart
Compression-regionwheretheairparticlearecloser
Medium-thesubstanceormaterialwhichcarriesthewave.(waterairsolids)
Transversewave-(lightwater)Directionofwavemotionisverticaltotheparticlemotion
Longitudinalwave-(soundwave)directionofwavemotionisinlinewiththedisplacementoftheparticles.
Progressivewave-wavethatcontinues.
Frequency-Thenumberofcompletewavesformedinasecond.MeasuredinHertz(Hz).
Amplitude-Themaximumdisplacementofthewavefromthemeanposition.
Wavelength-thedistancetravelledbyacompleteinmetreslambda(λ)
Simpleharmonicmotion-motionthatmakecompletecyclesoveraperiodoftime.
Vibration-continuousmovementofparticles.
Slinky-
Transverseprogressivewave-Thedirectionofwavemotionisperpendiculartothedisplacementoftheparticles.
Awavetransportonlyenergyandnottheparticles-energytransportphenomenon
Sinewave-sinusoidalwave.
Timeperiod-timetakestomakeonecompletewave,oscillation.F=1/TT=1/f=1/hertz=second
Speedofsound-350m/s
Speedoflight-3×
10^5km/s
Mechanicalwave-wavethatrequireamediumtopassthrough.(ex:
sound,water)
Universalwaveequation-velocity(orspeed)=frequency×
wavelength.V=fλ
PLO-propertiesofwaves.
1)Reflection
Lightwaves:
reflectionisbouncingofwaveswhentheyhitareflectingsurfacewaveswhentheyhitareflectingsurface.
Lawofreflection:
-Theangleofincidenceisequaltotheangleofreflection∠i=∠r
-theincidentray,reflectedrayandthenormallieonthesameplane.
Waterwaves:
Reflectlikelightwaves.Refractwhentheytravelfromdeeptoshallowregion.
Rippletank:
Speedofthewavesdecreaseswavelengthdecreasesfrequencyremainsunchanged.
Soundwaves:
reflectwhentheyhitobjects.
2)Refraction
Refractionmeansbendingwavesreflectwhentheytravelfromonemediumtotheother.
-thespeedoflightincreasedwhenitgoesintothelessdensemedium.(anglebecomebigger)
-thespeedoflightdepressedwhenitgoesintothemoredensemedium.(anglebecomesmaller)
Absoluterefractiveindex=(speedoflightinvacuum)/(speedoflightinmedium)n=C/V
Relativerefractiveindex:
Iflighttravelsfromairtoglasswetalkaboutrelativerefractiveindex.
Sini/Sinr=refractiveindex
Machnumber-theratioofthespeedofanobjecttothespeedofsound.
Sonicboom-thegreatsoundhappenedwhentheairplaneflyinahighspeedacrossthecompressedairinfront.
Decibel
Reverberation
Sonar
Radar:
PLO-propertiesofwaves:
Diffraction:
wavesbecomecircularwhentheyenteranarroworwideopening.
Narrowopening:
(greaterthewavelength,greaterthediffraction)
Wideopening:
Curvedonlyattheedges.
Interference:
-ConstructiveInterference
DestructiveInterference:
Theytendtocancelout.
Dopplereffect:
Thefrequencyofasourceincreasseswhenitapproachesthereceiver.
Polarisation:
Changingthevibrationalmodesofelectromagneticradiation.
PLO-Images
-Inopticalinstrumentstheimagesareformedwhenlenses(or)mirrorsareused.
-Theimagethatisformedonascreeniscalledarealimage.
-Theimagethatisnotformedonascreeniscalledavirtualimage.
Characteristicsofimage:
-real
-inverted
-smallerthantheobject
-inPhysicsthecharacteristicsoftheimagearestatedintermsof