1.speed=distance/timetaken2.velocity=displacement/timetaken
NAME:
3.displacement:distancemovedbyanobjectinaparticulardirection4.scalar:hasonlymagnitude5.vector:hasmagnitudeanddirection6.acceleration:therateofchangeofvelocity7.mass:propertyofabodyresistingchangesinmotion8.weight:forceduetogravitationalforce
9.centreofgravity:thepointwhereallthepointisconsidered.
10.Newton’sfirstlaw:Anobjectwillremainatrestortravellingatconstantvelocityinastraightlineunlessitisactedonbyaresultantforce.
11.Newton’ssecondlaw:Forabodyofconstantmass,itsaccelerationisdirectlyproportionaltotheforceappliedtoit.
12.Newton’sthirdlaw:whentwobodiesinteract,theforcestheyexertoneachotherareequalinmagnitudeandoppositeindirection.
13.moment:force×perpendiculardistanceofthepivotfromthelineofactionoftheforce.
14.couple:force×distancebetweentwoforces
15.principleofconservationofmoment:Foranyobjectthatisequilibrium,thesumoftheclockwisemomentaboutanypointprovided
bytheforcesactingontheobjectequalsthesumoftheanticlockwisemomentsaboutthatsamepoint.16.equilibrium:resultantforce=0
resultantmoment=0
17.workdone:productofforceanddistancemovedinthedirectionoftheforce
18.gravitationalpotentialenergy(g.p.e.):theenergytodoworkofamassthatithasstoredduetoitspositioninagravitationalfield.
19.kineticenergy(k.e.):energytodoworkofanobjecthasduetoitsvelocity.
20.conservationofenergy:Energycannotbecreatedordestroyed.Itcanonlybeconvertedfromonetoanother.
21.momentum:theproductofitsmassanditsvelocity
22.principleofconservationofmomentum:Foraclosedsystem,thetotalmomentumbeforethecollisionequalsthetotalmomentumafterthecollision.
23.force:therateofchangeofmomentum.
24.perfectlyelasticcollision:relativespeedofapproach=relativespeedofseparation.
25.Density:massperunitvolume26.Pressure:forceperunitarea
27.Hooke’slaw:AmaterialsobeysHooke'slawiftheextensionproducedinitisproportionaltotheappliedforce
28.Stress:forceperunitarea
29.Strain:extensionperunitoriginallength30.Youngmodulus:stress/strain
31.Elasticdeformation:Materialreturnstoitsoriginalshapewhenforcesareremoved
32.Plasticdeformation:MaterialdoesNOTreturntoitsoriginalshapewhenforcesareremoved
33.Electricfields:Anelectricfieldisaregioninwhichchargedbodiesexperienceaforce.
34.electricfieldstrength:Theelectricfieldstrengthatapointelectricforceperunitthatpoint.
35.Electriccurrent:istherateofflowofelectricchargepastapoint36.Coulomb:isthechargewhichflowspastapointinacircuitinatimeof1swhenthecurrentis1A
37.Potentialdifference:energyisconvertedfromelectricaltootherformsperunitcharge
38.Electromotiveforce:energyisconvertedfromotherformstoelectricalperunitcharge
39.Resistance:potentialdifference/current40.Ohm:volt/ampere
41.Power:workdone/timetaken
isthe
chargeexertedonastationarypositivechargeat
42.Kirchhoff'sfirstlaw:Thesumofthecurrentsenteringanypointinacircuitisequaltothesumofthecurrentleavingthatsamepoint.43.Kirchhoff'ssecondlaw:thesumofe.m.f.saroundanyloopisequaltothesumofp.d.saroundtheloop.
44.Ohm’slaw:AconductorobeysOhm'slawifthecurrentinitisdirectlyproportionaltothepotentialdifferenceacrossitsends.
45.Amplitude:isthemaximumdisplacementofthemediumfromitsequilibriumposition.
46.Wavelength:istheminimumdistancebetweentwopointswhichareinphase
47.Frequency:isthenumberofcompleteoscillationsinonesecond48.Period:isthetimetakenforonecompleteoscillation.
49.Wavespeed:isthedistancetraveledbyawaveformperunittime.50.Longitudinal:vibrationsoftheparticlesareparalleltothewavedirection
51.Transverse:vibrationsoftheparticlesareperpendiculartothewavedirection
52.Dopplereffect.theobservedfrequencyisdifferenttotheemittedfrequencywhenthereisrelativemotionbetweenthesourceandobserver.53.Superpositionofwaves:whentwoormorewavesatapoint,theresultantdisplacementisthealgebraicsumofthedisplacementsoftheindividualwaves
.node:equilibriumposition55.antinode:maximumdisplacement
56.DifferencebetweenprogressivewavesandstationarywavesProgressivewaves
progressivewavestransferenergy.
Stationarywaves
stationarywavesdoesnottransferenergy
Allparticleshavedifferentphases
Allthepointsbetweenadjacentnodesareinphase
AllthepointsalongthewavehaveTheamplitudeofdifferentpointssameamplitude.
varyfromamaximumtozero.
57.Interference:isthesuperpositionoftwoormorewavesinsimilardirectiontogivearesultantwavewhoseamplitudeisgivenbytheprincipleof
superposition.
58.Coherent:identicalwavelengthsandfrequencyconstantphasedifference
59.Diffraction:Thespreadingoutofwavewhenwavespassthroughagap
60.Isotopes:arenucleiofthesameelementwithdifferentnumbersofneutronsbutthesamenumberofprotons.
61.Hadrons['hædrɒn]:suchasprotonsandneutrons.Theseareallparticlesthatareactedbythestrongnuclearforce.
62.Leptons['leptɒn]:suchaselectrons.Theseareparticlesthatarenot
actedbythestrongnuclearforce.
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