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S A M P L ESYSTEMS ENGINEERING
Written examination
Day Date Reading time: **.** ** to **.** ** (15 minutes) Writing time: **.** ** to **.** ** (1 hours 30 minutes)
QUESTION AND ANSWER BOOK
Structure of bookSection Number of
questionsNumber of questions
to be answeredNumber of
marks
A 20 20 20B 19 19 80
Total 100
• Studentsarepermittedtobringintotheexaminationroom:pens,pencils,highlighters,erasers,sharpeners,rulersandonescientificcalculator.
• StudentsareNOTpermittedtobringintotheexaminationroom:blanksheetsofpaperand/orwhiteoutliquid/tape.
Materials supplied• Questionandanswerbookof24pagesincludingformulasonpage24.• Answersheetformultiple-choicequestions.
Instructions• Writeyourstudent numberinthespaceprovidedaboveonthispage.• Checkthatyournameandstudent numberasprintedonyouranswersheetformultiple-choice
questionsarecorrect,andsignyournameinthespaceprovidedtoverifythis.• Allcalculationsmustshowappropriateformulasandworking.
• AllwrittenresponsesmustbeinEnglish.
At the end of the examination• Placetheanswersheetformultiple-choicequestionsinsidethefrontcoverofthisbook.
Students are NOT permitted to bring mobile phones and/or any other unauthorised electronic devices into the examination room.
©VICTORIANCURRICULUMANDASSESSMENTAUTHORITY2013
Version3–December2017
SUPERVISOR TO ATTACH PROCESSING LABEL HEREVictorian Certificate of Education Year
STUDENT NUMBER
Letter
SYSENGEXAM(SAMPLE) 2 Version3–December2017
SECTION A – continued
Question 1Aboatwinchhasadrivergearof20teethandadrivengearof160teeth.Whatisthegearratio?A. 0.125:1B. 1:8C. 8:1D. 16:1
Question 2Whenanewproduct(forexample,anewcar)isdesignedforthemarket,extensivefield-testingisusuallycarriedoutontheproduct.ThepurposeofthistestingistocheckwhetherA. theproductwillsell.B. peoplewillliketheproduct.C. theproducthastherightrangeofcolours.D. theproductperformstoitsdesignrequirements.
Question 3
gear Z
gear Y
gear X
Inthediagramabove,ifgearXmovesclockwisethengearZwillrotateA. clockwiseandfasterthangearX.B. clockwiseandslowerthangearX.C. anticlockwiseandfasterthangearX.D. anticlockwiseandslowerthangearX.
SECTION A – Multiple-choice questions
Instructions for Section AAnswerall questionsinpencilontheanswersheetprovidedformultiple-choicequestions.Choosetheresponsethatiscorrect forthequestion.Acorrectanswerscores1,anincorrectanswerscores0.Markswillnotbedeductedforincorrectanswers.Nomarkswillbegivenifmorethanoneansweriscompletedforanyquestion.Unlessindicateddiagramsarenottoscale.
Version3–December2017 3 SYSENGEXAM(SAMPLE)
SECTION A – continuedTURN OVER
Question 4ThecorrectworksequencetoreducetheriskofinjurytoapersonisA. riskassessment,hazardidentification,riskcontrol.B. hazardidentification,riskassessment,riskcontrol.C. riskassessment,riskcontrol,hazardidentification.D. riskcontrol,hazardidentification,riskassessment.
Question 5A20-cm-longspannerisusedtoproduceatorqueof60Nm.TheforceappliedtothespannerisA. 3NB. 12NC. 120ND. 300N
Use the following information to answer Questions 6 and 7.
A
B
CD
Question 6 Thehydraulicpumpmovesfluidfromatanktotheoutlet.TherotorsAandBhaverotarymotionthatisA. clockwiseforboth.B. anticlockwiseforboth.C. clockwiseforAandanticlockwiseforB.D. anticlockwiseforAandclockwiseforB.
Question 7ThefluidpressuresareA. zeroatpointCandpointD.B. thesameatpointCandpointD.C. highatpointCandlowatpointD.D. lowatpointCandhighatpointD.
SYSENGEXAM(SAMPLE) 4 Version3–December2017
SECTION A – continued
Question 8
car handbrake
X
Y
Z
Onthediagramofthecarhandbrakeleverabove,whatarethecorrectpositionsoftheeffort,loadandfulcrum?
Effort Load Fulcrum
A. X Y ZB. Z Y XC. Y X ZD. X Z Y
Question 9
500 mm
200 mm
cable
car handbrakeforce
Onthediagramabove,theforceappliedtothehandbrakeleverbytheoperator’shandis40N.Whatistheforceappliedtothecable?A. 100NB. 200NC. 300ND. 700N
Version3–December2017 5 SYSENGEXAM(SAMPLE)
SECTION A – continuedTURN OVER
Question 10AsemiconductorisusedintheconstructionofA. arelay.B. atransformer.C. alight-emittingdiode(LED).D. anelectrolyticcapacitor.
Question 11
4 nf 6 nf
Whatisthetotalcapacitanceofthecircuitshownabove?A. 2nfB. 2.4nfC. 10nfD. 24nf
Question 12Batteriescanbeconnectedinseriesorinparallel.ThemainreasonforconnectingbatteriesinparallelistoincreasetheA. availablecurrent.B. voltageavailable.C. internalresistance.D. externalresistance.
SYSENGEXAM(SAMPLE) 6 Version3–December2017
SECTION A – continued
Question 13
let D1 = 0
start
stop
let D1 = 1 + D1
let D0 = 0
let D0 = 1 + D0
wait 1
wait 1
D0 = 5N
N
Y
Y
low 0
D1 = 5
high 0
Aflowchartforamicrocontrollerprogramisshownabove.‘High0’turnsanLEDon.‘Low0’turnsitoff.‘Wait1’isaone-seconddelay.HowmanytimeswilltheLEDturnonandoffinthisprogram?A. onceB. 10timesC. 20timesD. 25times
Question 14
voltage
time
Thedisplayonacathoderayoscilloscopeisshownabove.Giventhatthehorizontalscaleis0.01secondsperdivisionandtheverticalscaleis2Vperdivision,thevoltageandfrequencyoftheabovesignalareA. 3Vand1HzB. 3Vand2HzC. 6Vand50HzD. 6Vand100Hz
Version3–December2017 7 SYSENGEXAM(SAMPLE)
SECTION A – continuedTURN OVER
Question 15
driven gear
driver gear
Thedriverinthegearabovehas8teethandturnsclockwise.Thedrivengearhas22teeth.Whatisthegearratioofthedrivengeartothedrivegearandthedirectionofrotationofthedrivengear?A. 4:11clockwiseB. 4:11anticlockwiseC. 11:4clockwiseD. 11:4anticlockwise
Question 16Solderwire,usedintheconstructionofelectroniccircuitsinthepast,containedametalthatislinkedtoahealthhazard.ThishazardousmetalwasA. tin.B. iron.C. lead.D. copper.
Question 17
Forward voltage Current drawn
Green 2.1V 20mA
Blue 3.5V 20mA
Thetableaboveshowsthespecificationsfor5mmgreenand5mmblueLEDs.ThegreenLEDcomparedtotheblueoneA. haslowerresistance.B. hashigherresistance.C. consumesmorepower.D. consumesthesameamountofpower.
SYSENGEXAM(SAMPLE) 8 Version3–December2017
END OF SECTION A
Question 18
1 14 VDD + 3 –15 V
VSS 0 V
2 13
3 12
4 11
5 10
6 9
7 8
The4011integratedcircuitshownabovehasfourlogicgates.Totestthelogicgateconnectedtopins1,2and3,voltagevaluesaremeasuredandrecordedashighorlow.Whichtablebelowrepresentsthecorrectoperationofthatlogicgate?
A. B. C. D.
Pin Voltage
1 low
2 low
3 low
Pin Voltage
1 high
2 low
3 low
Pin Voltage
1 high
2 high
3 low
Pin Voltage
1 low
2 high
3 low
Question 19Anundersizedelectricalcableisselectedtoconnectapowersupplytoanoperatingcircuit.ThemajorhazardthatislikelytooccuristhattheelectricalcablewillA. break.B. overheat.C. shortcircuit.D. nothaveenoughresistance.
Question 20
VIN = 240 VAC200 windings
VOUTNs = 20
ThevalueofthevoltageacrosstheoutputwindingsisA. 12 VB. 24VC. 240VD. 2400V
Version3–December2017 9 SYSENGEXAM(SAMPLE)
SECTION B – continuedTURN OVER
The following information relates to Questions 1–18.Avehicleistobeconstructedsothatitispoweredbyanelectricengine.Therearetwomainsubsystemsinthevehicle:themechanicalsubsystemandtheelectrical/electronicsubsystem.TwopossibleoutlinesoftheconceptaregiveninFigure1.
Figure 1
Question 1 (1mark)Whyisthisvehicleconsideredtobeanintegratedsystem?
Question 2 (4marks)Oneperformancespecificationofthevehicleisthatitshouldbeabletotravelataconstantspeedfor140km.a. Givetwootherappropriateperformancespecificationsthatcouldbeincludedinthedesign
brief. 2marks
1.
2.
b. Describeatestforoneoftheperformancespecificationsthatyounamedinpart a. 2marks
SECTION B
Instructions for Section BAnswerall questionsinthespacesprovided.Unlessindicatedthediagramsarenottoscale.
SYSENGEXAM(SAMPLE) 10 Version3–December2017
SECTION B – continued
Question 3 (6marks)AsshowninFigure1,thevehiclecouldbeeitherathree-orfour-wheeledvehicle.a. Discusstwoissuesthatwouldarisewhendecidingwhichwheellayouttouse. 4marks
b. Theclienthasdecidedtoconstructathree-wheeledvehicle(tricycle). Givetwosafetyconsiderationsthatneedtobeaddressedwhendesigningthelayoutofthe
tricycle. 2marks
Version3–December2017 11 SYSENGEXAM(SAMPLE)
SECTION B – continuedTURN OVER
Question 4 (6marks)Thebuilderofthevehiclewantstoexplorethepossibilityofpoweringthevehiclewithnewtechnology.Hedoesnotwanttousefossilfuels.Atthisstage,thebuilderdoesnotwanttousesolarenergy.a. Nametworenewablesourcesofenergy(otherthansolarenergy). 2marks
1.
2.
b. Explainhowoneoftherenewablesourcesofenergythatyounamedinpart a.couldbeusedtopowerthetricycle. 2marks
c. Discussoneenvironmentaladvantageoftherenewablesourceofenergythatyoudescribedinpart b. 2marks
SYSENGEXAM(SAMPLE) 12 Version3–December2017
SECTION B – continued
Question 5 (5marks)
solar panel
Thebuilderofthevehicleeventuallydecidestochargethebatteryusingsolarpanels.Thebuilderdecidestousea2m2panelthatgeneratesapeakoutputof100W.a. Calculatehowmanywattsofsolarpowerwillfallonthesolarpanelifthesolarcellsare
20percentefficient. 2marks
Theprocessofchargingthebatteryis90percentefficient.Themotorthatisusedis85percentefficient.b. Calculatethecombinedefficiencyofthebatterysystemandoperatingthemotor. 1mark
c. Whatmightbeonedisadvantageofpoweringthetricyclewithsolartechnology? 2marks
Version3–December2017 13 SYSENGEXAM(SAMPLE)
SECTION B – continuedTURN OVER
Question 6 (3marks)Onedesignoptionforthevehicleistoincorporateaself-centringsteeringmechanism.Anotherdesignoptionistohavetheshaftsatanangle.
a a
shaft
height
Figure 2
a. Whathappenstotheheightofthevehiclewhenthewheelschangedirection? 1mark
b. Intermsofpotentialenergy,explainhowtheself-centringmechanismwouldwork. 2marks
SYSENGEXAM(SAMPLE) 14 Version3–December2017
SECTION B – continued
Question 7 (7marks)a. Designasafesteeringmechanismforthetricycle.Drawandlabelthepartsonthediagram
below. 3marks
b. Listtwoprocessesthatwillbeneededtoconstructthesteeringmechanism. 2marks
1.
2.
c. Giveadifferentsafetyprecautionforeachoftheprocessesthatyoudescribedinpart b. 2marks
1.
2.
Version3–December2017 15 SYSENGEXAM(SAMPLE)
SECTION B – continuedTURN OVER
Question 8 (5marks)Achainaroundthetwo-cogdrivesystemisadesignoptionforthetricycle.Dataisshowninthetablebelow.
speedoftricycle 40.0km/hor11.1m/s
rpmofaxle 600rpm
cogsavailable teethfrom10to60
motorspeed 6000rpm
a. Calculatethecircumferenceofthewheel. 2marks
b. Drawadrivesystemonthediagrambelowthatwouldsatisfytheconditionsstatedinpart a. andthetableabove.Givethenumberofteethoneachcog.Justifyyouranswerbyshowingrelevantcalculations. 3marks
motoraxle
SYSENGEXAM(SAMPLE) 16 Version3–December2017
SECTION B – continued
Question 9 (4marks)Ahydraulicdiscbrakingsystemistobeusedonthevehicle.Thediameterofthediscbrakecylinderis60.0mmandthediameterofthemastercylinderis20.0mm.ThebrakingsystemisshowninFigure3.
master cylinder
brake pedaldisc brakecylinder
axle
disc
brake pads
Figure 3
a. Calculatethepressureinthesystemifaforceof120.0Nisappliedtothebrakepedal.Includeanyworkingandthefinalunits.Giveyouranswertothreesignificantfigures. 2marks
b. Calculatetheforceappliedtoeachofthebrakepads.Giveyouranswerinnewtons(N)andtothreesignificantfigures. 2marks
Question 10 (2marks)Thetricycleistobepoweredbya200Wmotorwithasupplyvoltageof40Vatmaximumoutput.Calculatethecurrentthroughthemotor.
Version3–December2017 17 SYSENGEXAM(SAMPLE)
SECTION B – continuedTURN OVER
Question 11 (3marks)Themotoristobewiredupwithaswitch,battery,ammeterandapotentiometerthatisusedtovarythespeed.Completethewiringdiagrambelow.
A M
Question 12 (5marks)AgraphofpowerconsumptionversusspeedisgiveninFigure4below.
20018016014012010080604020
5 10 15 20 25 30 35 40
Power consumption versus speed
power output (W)
speed (km/h)
Figure 4
a. UsetheinformationfromFigure4abovetocalculatetherangeofthetricycleifitistocruiseat25kmh–1.Assumethata40Vsupplytothemotoranda10Ahbatteryareused. 2marks
b. Howfarwillthetricycletravelatfullpower? 2marks
c. Explainwhythereisadifferenceintherangeofthetricycleatdifferentspeeds. 1mark
SYSENGEXAM(SAMPLE) 18 Version3–December2017
SECTION B – continued
Question 13 (4marks)Thetricycledoesnotmeettheperformancespecificationofhavingarangeof140km.Givetworecommendationsforchangestothetricycleinordertomeettheperformancespecificationabove.Justifyeachrecommendation.
1.
2.
Question 14 (4marks)Someoftheprocessesintheconstructionofthetricycleareshownbelow.Constructaproductionsequenceforthetricyclebynumberingtheprocessesbelow.
Process Number
constructionofframe
computer-simulationofelectronics
constructionofsteeringsystem
installationofbrakes
mountingmotorandgearbox
simulationofmotorandgearbox
mountingwheels
wiringtheelectricalcomponents
Version3–December2017 19 SYSENGEXAM(SAMPLE)
SECTION B – Question 15 –continuedTURN OVER
Question 15 (7marks)Inordertomaintainthetricycleataconstantspeed,aspeedometerisrequired.Asystemsdiagramforaspeedometerisgivenbelow.
input device
AninputdeviceistobeattachedtothetricycletoproducethesignalshowninFigure5below.
9 volts
voltage
0 voltstime
Figure 5
a. ExplainwhythesignalshowninFigure5isconsideredadigitalsignal. 1mark
b. Nameaninputdevicethatcanbeusedonthetricycletoproducethesignalshownin Figure5. 1mark
c. Onthetricyclebelow,placetheinputdevicethatwasnamedinpart b.sothatitwillgeneratethesignal. 1mark
d. Howmanypulsesperrevolutionofthewheelarethereforthisinputdevice? 1mark
SYSENGEXAM(SAMPLE) 20 Version3–December2017
SECTION B – continued
e. Drawthisinputdeviceinacircuitdiagramsothatitwillproducethegivensignal.Labelallcomponents. 3marks
Question 16 (2marks)Amicrocontrolleristobeusedtoconvertthesignaltogiveadecimaloutputthatwilllaterbereadouton7-segmentdisplays.Thepinconfigurationofan18-pinmicrocontrollerisshowninFigure6.
123456789
181716151413121110
ADC 2/input 2serial out
serial inreset
0 Voutput 0
output 1/12c sdaoutput 2
output 3/pwn 3
input 1/ADC 1input 0/ADC 0/infraininput 7/keyboard datainput 8/keyboard clock+Voutput 7output 6output 5output 4/12c scl
microcontroller
Figure 6
a. Whichpinisconnectedtothevoltagesupply? 1mark
b. Thesignalfromthesensorwillbeconnectedtoapin. Nameapintowhichthesignalcanbeconnected. 1mark
Version3–December2017 21 SYSENGEXAM(SAMPLE)
SECTION B – continuedTURN OVER
Question 17 (4marks)Themicrocontrollerwillneedtobeprogrammedtoconverttheinputsignalfromthesensorintoadecimaloutputthatgivesthevelocity.Theinputsignalisfromyourinputsensorandthecircumferenceofthewheel is1.2m.Drawaflowchartorwriteashortprogramtoperformtheprocessofconvertingtheinputsignalfromthesensorintoadecimaloutput.Anyformulausedmustbestated.
SYSENGEXAM(SAMPLE) 22 Version3–December2017
SECTION B – continued
Question 18 (3marks)Themicrocontrollerhasacommandtoconvertadecimaloutputintoa4bitBinaryCounttoDecimal(BCD)signal.Thatis,abinarysignalthatcountsfrom0to9.Usingthe4bitoutputpinsofthemicrocontroller,thedecimaloutputcanbeconvertedtoaBCDsignal.(Eachdecimaldigitisrepresentedbya4bitbyte.)Thepinconfigurationofthe45117-segmentdriveranda7-segmentdisplayaregivenbelow.
1
4511
16
2 15
3 14
4 13
5 12
6 11
7 10
8 9
+2 to +6 V HC+5 V LS/HCToutput f
output g
output a
output b
output c
output d
output e
input B (2)
input C (4)
display test
blank output
blank input
input D (8)
input A (1)
0 V
g f Gnd a b
e d Gnd c dp
a
bf
g
ce
d
common cathode
Figure 7
Completethecircuitboarddiagrambelowthatcanconvertthemicrocontrollersignaltoa7-segmentdisplay.Althoughnotdesirable,asingleresistorhasbeenputinserieswiththedisplay.
input Ainput Binput Cinput D
Version3–December2017 23 SYSENGEXAM(SAMPLE)
END OF SECTION B
Question 19 (5marks)Emergingtechnologiesincludemotorvehiclesthatareconsideredtobelow-orno-emissionvehicles.Theseincludethefollowing.
Type 1: Hybrid Ahybridispoweredbyasmallerthannormalinternalcombustionengine.Extrapowerisprovidedbyanelectricmotorthatissuppliedbyabatteryforstop-startcitydrivingandacceleration.Thisvehicleisconsideredtobealow-emissionvehicleandhasarangesimilartoconventionalvehicles.
Type 2: Rechargeable batteryAnothertypeisavehiclepoweredentirelybyanelectricmotorthatissuppliedfromabatteryandhasarangeof80–100km.Thebatterycanberechargedfrommainselectricity,thereforeemittingnoemissionsfromthevehicleinoperation.Thevehiclealsocontainsanengine-poweredgeneratorthat,whenactivated,canextendtherangemuchfurtherbyrechargingthebatterywhilebeingdriven.Thevehicleisalsoconsideredtobelow-emissionwheninthe‘enginechargingthebattery’mode.
Type 3: Mains-only rechargeable batteryAthirdvehicleonthemarketisanelectricvehiclethatispoweredentirelybyanelectricmotorthatissuppliedfromalargerbatterythatgivesitarangeofapproximately150km.Thebatterycanberechargedonlyfrommainselectricity,thereforeemittingnoemissionsfromthevehicleinoperation.
Analysetheadvantagesanddisadvantagesofusingeachtypeofmotorinacityenvironment.
SYSENGEXAM(SAMPLE) 24 Version3–December2017
END OF QUESTION AND ANSWER BOOK
Gearratiofinal=gearratio1×gearratio2
Efficiency = output energyinput energy
× 100%
Voltage=current×resistance
Resistorsinparallel:Rt=R RR R
1 2
1 2
×
+
ColourcodesColour Valueblack 0brown 1red 2orange 3yellow 4green 5blue 6violet 7grey 8white 9gold 5%silver 10%
Resistorsinseries:Rt=R1 +R2
Power=voltage×current
Areaofcircle=�r2 (�=3.14)
Circumferenceofcircle=2�r
Force=pressure×area
gear A rpmgear B rpm
number of teeth gear Bnumber of teeth
= gear A
pulley A rpmpulley B rpm
radius of pulley Bradius of pulle
=yy A
Speed = distancetime
Gear ratio = number of teeth on driven gearnumber of teeth on driver gear
Mechanical advantage loadeffort
=
Torque=force×distance
Frequency = 1period
EfficiencyTotal=Efficiency1×Efficiency2
Formula sheet
Version3–December2017 25 SYSENGEXAM(SAMPLE)
Answers to multiple-choice questions
Question Answer
1 C
2 D
3 B
4 B
5 D
6 C
7 C
8 D
9 A
10 C
11 B
12 A
13 D
14 C
15 C
16 C
17 A
18 C
19 B
20 B
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