AQA GCSE Combined Science
Physics -with correct answers 2025
Energyvisvtransferredvbetweenvstoresv-vcorrect-answers-
Thermal,vkinetic,vgravitationalvpotential,velasticvpotential,vchemical,vmagnetic,velectrostatic,vnucle
ar
Energyvisvtransferred...v-vcorrect-answers-
Mechanicallyv(byvavforcevdoingvwork),velectricallyv(workvdonevbyvmovingvcharges),vbyvheatingvorvb
yvradiationv(likevlightvorvsound)
Whenvavsystemvchanges,venergyvisvtransferredv-vcorrect-answers-
Itvcanvbevtransferredvintovorvawayvfromvthevsystem,vbetweenvobjectsvinvthevsystemvorvbetweenvdiff
erentvtypesvofvenergyvstores.vClosedvsystemsvarevwherevneithervmattervnorvenergyvcanventervorvle
ave.vThevnetvchangevinvthevtotalvenergyvofvavclosedvsystemvisvalwaysv0
kineticvenergyv-vcorrect-answers-energyvofvmotionv-
vthevgreatervanvobject'svmassvandvthevfastervitvisvgoing,vthevmorevenergyvtherevwillvbevinvitsvkineticv
energyvstore.vEkv(j)v=v1/2m(kg)v(m/s)vsquared
Raisedvobjectsvstorevenergyvinvgravitationalvpotentialvenergyvstoresv-vcorrect-answers-
liftingvanvobjectvinvavgravitationalvfieldvrequiresvwork,vcausingvanvenergyvtransfervtovthevthevGPEvst
orevofvthevobject.vEp(j)v=vm(kg)g(n/kg)h(m)
,Fallingvobjectsvtransfervenergyv-vcorrect-answers-
FallingvobjectsvtransfervenergyvfromvitsvGPEvstorevtovitsvkineticvenergyvstore.vWhenvthere'svnovairvr
esistance,venergyvlostvfromvthevGPEvstorev=venergyvgainedvinvthevkineticvenergyvstore
Stretchingvtransfersvenergyvtovelasticvpotentialvenergyvstoresv-vcorrect-answers-
Asvlongvasvthevlimitvofvproportionalityvhasvnotvbeenvexceeded,vEev(j)v=v1/2vkv(N/m)vev(m)vsquared
specificvheatvcapacityv-vcorrect-answers-
thevenergyvrequiredvtovraisevthevtemperaturevofvonevgramvofvavsubstancevbyvonevdegreevCelsius.v
Ev(j)v=vm(kg)vc(j/kgdegree)v thetav(degreesvCelsius)
Conservationvofvenergyvprinciplev-vcorrect-answers-
Energyvcanvbevtransferredvbutvcanvnevervbevcreatedvofvdestroyed
Dissipatedvenergyv-vcorrect-answers-
energyvusedvupvinvavsystem,vtypicallyvlostvduevtovworkvdonevbyvfriction,v'wastedvenergy'
Phonevenergyv-vcorrect-answers-
Whenvyouvusevthevphone,venergyvisvusefullyvtransferredvfromvthevchemicalvenergyvstorevofvthevbat
teryvinvthevphone,vbutvsomevofvthisvenergyvisvdissipatedvtovthermalvenergy
Closedvsystemvenergyvtransferv-vcorrect-answers-
Avcoldvspoonvisvdroppedvintovhotvsoupvinvanvinsulatedvflask,vwhichvisvthenvsealed.vEnergyvisvtransfe
rredvfromvthevthermalvenergyvstorevofvthevsoupvtovthevuselessvthermalvenergyvofvthevspoon
Powerv-vcorrect-answers-Thevratevatvwhichvworkvisvdonev(watts).vP(w)v=vE(j)v/vt(s)
Powerfulvmachinev-vcorrect-answers-Onevwhichvtransfersvavlotvofvenergyvinvavshortvspacevofvtime
, Conductionvoccursvmainlyvinvsolidsv-vcorrect-answers-
Conductionvisvthevprocessvwherevvibratingvparticlesvtransfervenergyvtovneighbouringvparticles.
Longvdefinitionvofvconductionv-vcorrect-answers-
Energyvtransferredvtovanvobjectvbyvheatingvisvtransferredvtovthevthermalvstore,vwhichvisvsharedvacr
ossvthevkineticvstorevofvthevparticles.vThevparticles'vcollisionsvcausevenergyvtovbevtransferredvbetw
eenvparticlesvkineticvenergyvstores.
thermalvconductivityv-vcorrect-answers-
thevMrsvsurevofvthevratevatvwhichvthermalvenergyvcanvtravelvthroughvavmaterial
Convectionvoccursvonlyvinvliquidsvandvgasesv-vcorrect-answers-
Convectionvisvwherevenergeticvparticlesvmovevawayvfromvhottervtovcoolervregions
Convectionvlongervdefinitionv-vcorrect-answers-
Unlikevinvsolids,vthevparticlesvinvliquidsvandvgasesvarevablevtovmove.vWhenvyouvheatvavregionvofvavg
as/liquid,vthevparticlesvmovevfastervandvthevspacevbetweenvparticlesvincreases.vThisvcausesvthevde
nsityvofvthevregionvtovdecrease.vBecausevtheyvcanvflow,vthevwarmervandvlessvdensevregionvwillvrisev
abovevdenservcoolervregions.vIfvtherevisvavconstantvheatvsource,vavconvectionvcurrentvwillvbevmade
Radiatorsv-vconvectionvcurrentsv-vcorrect-answers-
Energyvisvtransferredvfromvthevradiatorvtovnearbyvairvparticlesvbyvconduction.vThevairvbyvthevradiat
orvbecomesvwarmervandvlessvdense.vThisvwarmvairvrisesvandvisvreplacedvbyvcoolervair.vAtvthevsamev
time,vthevpreviouslyvheatedvairvtransfersvenergyvtovthevsurroundingvandvcools,vbecomesvdenser,va
ndvsinks.vThisvcyclevrepeatsvandvcausesvavflowvofvairvtovcirculatevaroundvthevroom
Howvtovreducevunwantedvenergyvtransfersv-vcorrect-answers-Lubricationvandvthermalvinsulation
Lubricationvreducesvfrictionalvforcesv-vcorrect-answers-
Whenvsomethingvmoves,vthere'svatvleastvonevfrictionalvforcevactingvonvit,vcausingvsomevenergyvtov
Physics -with correct answers 2025
Energyvisvtransferredvbetweenvstoresv-vcorrect-answers-
Thermal,vkinetic,vgravitationalvpotential,velasticvpotential,vchemical,vmagnetic,velectrostatic,vnucle
ar
Energyvisvtransferred...v-vcorrect-answers-
Mechanicallyv(byvavforcevdoingvwork),velectricallyv(workvdonevbyvmovingvcharges),vbyvheatingvorvb
yvradiationv(likevlightvorvsound)
Whenvavsystemvchanges,venergyvisvtransferredv-vcorrect-answers-
Itvcanvbevtransferredvintovorvawayvfromvthevsystem,vbetweenvobjectsvinvthevsystemvorvbetweenvdiff
erentvtypesvofvenergyvstores.vClosedvsystemsvarevwherevneithervmattervnorvenergyvcanventervorvle
ave.vThevnetvchangevinvthevtotalvenergyvofvavclosedvsystemvisvalwaysv0
kineticvenergyv-vcorrect-answers-energyvofvmotionv-
vthevgreatervanvobject'svmassvandvthevfastervitvisvgoing,vthevmorevenergyvtherevwillvbevinvitsvkineticv
energyvstore.vEkv(j)v=v1/2m(kg)v(m/s)vsquared
Raisedvobjectsvstorevenergyvinvgravitationalvpotentialvenergyvstoresv-vcorrect-answers-
liftingvanvobjectvinvavgravitationalvfieldvrequiresvwork,vcausingvanvenergyvtransfervtovthevthevGPEvst
orevofvthevobject.vEp(j)v=vm(kg)g(n/kg)h(m)
,Fallingvobjectsvtransfervenergyv-vcorrect-answers-
FallingvobjectsvtransfervenergyvfromvitsvGPEvstorevtovitsvkineticvenergyvstore.vWhenvthere'svnovairvr
esistance,venergyvlostvfromvthevGPEvstorev=venergyvgainedvinvthevkineticvenergyvstore
Stretchingvtransfersvenergyvtovelasticvpotentialvenergyvstoresv-vcorrect-answers-
Asvlongvasvthevlimitvofvproportionalityvhasvnotvbeenvexceeded,vEev(j)v=v1/2vkv(N/m)vev(m)vsquared
specificvheatvcapacityv-vcorrect-answers-
thevenergyvrequiredvtovraisevthevtemperaturevofvonevgramvofvavsubstancevbyvonevdegreevCelsius.v
Ev(j)v=vm(kg)vc(j/kgdegree)v thetav(degreesvCelsius)
Conservationvofvenergyvprinciplev-vcorrect-answers-
Energyvcanvbevtransferredvbutvcanvnevervbevcreatedvofvdestroyed
Dissipatedvenergyv-vcorrect-answers-
energyvusedvupvinvavsystem,vtypicallyvlostvduevtovworkvdonevbyvfriction,v'wastedvenergy'
Phonevenergyv-vcorrect-answers-
Whenvyouvusevthevphone,venergyvisvusefullyvtransferredvfromvthevchemicalvenergyvstorevofvthevbat
teryvinvthevphone,vbutvsomevofvthisvenergyvisvdissipatedvtovthermalvenergy
Closedvsystemvenergyvtransferv-vcorrect-answers-
Avcoldvspoonvisvdroppedvintovhotvsoupvinvanvinsulatedvflask,vwhichvisvthenvsealed.vEnergyvisvtransfe
rredvfromvthevthermalvenergyvstorevofvthevsoupvtovthevuselessvthermalvenergyvofvthevspoon
Powerv-vcorrect-answers-Thevratevatvwhichvworkvisvdonev(watts).vP(w)v=vE(j)v/vt(s)
Powerfulvmachinev-vcorrect-answers-Onevwhichvtransfersvavlotvofvenergyvinvavshortvspacevofvtime
, Conductionvoccursvmainlyvinvsolidsv-vcorrect-answers-
Conductionvisvthevprocessvwherevvibratingvparticlesvtransfervenergyvtovneighbouringvparticles.
Longvdefinitionvofvconductionv-vcorrect-answers-
Energyvtransferredvtovanvobjectvbyvheatingvisvtransferredvtovthevthermalvstore,vwhichvisvsharedvacr
ossvthevkineticvstorevofvthevparticles.vThevparticles'vcollisionsvcausevenergyvtovbevtransferredvbetw
eenvparticlesvkineticvenergyvstores.
thermalvconductivityv-vcorrect-answers-
thevMrsvsurevofvthevratevatvwhichvthermalvenergyvcanvtravelvthroughvavmaterial
Convectionvoccursvonlyvinvliquidsvandvgasesv-vcorrect-answers-
Convectionvisvwherevenergeticvparticlesvmovevawayvfromvhottervtovcoolervregions
Convectionvlongervdefinitionv-vcorrect-answers-
Unlikevinvsolids,vthevparticlesvinvliquidsvandvgasesvarevablevtovmove.vWhenvyouvheatvavregionvofvavg
as/liquid,vthevparticlesvmovevfastervandvthevspacevbetweenvparticlesvincreases.vThisvcausesvthevde
nsityvofvthevregionvtovdecrease.vBecausevtheyvcanvflow,vthevwarmervandvlessvdensevregionvwillvrisev
abovevdenservcoolervregions.vIfvtherevisvavconstantvheatvsource,vavconvectionvcurrentvwillvbevmade
Radiatorsv-vconvectionvcurrentsv-vcorrect-answers-
Energyvisvtransferredvfromvthevradiatorvtovnearbyvairvparticlesvbyvconduction.vThevairvbyvthevradiat
orvbecomesvwarmervandvlessvdense.vThisvwarmvairvrisesvandvisvreplacedvbyvcoolervair.vAtvthevsamev
time,vthevpreviouslyvheatedvairvtransfersvenergyvtovthevsurroundingvandvcools,vbecomesvdenser,va
ndvsinks.vThisvcyclevrepeatsvandvcausesvavflowvofvairvtovcirculatevaroundvthevroom
Howvtovreducevunwantedvenergyvtransfersv-vcorrect-answers-Lubricationvandvthermalvinsulation
Lubricationvreducesvfrictionalvforcesv-vcorrect-answers-
Whenvsomethingvmoves,vthere'svatvleastvonevfrictionalvforcevactingvonvit,vcausingvsomevenergyvtov