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2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Engineering Studies
General Instructions
•Readingtime–5minutes
•Workingtime–3hours
•Writeusingblackpen
•Drawdiagramsusingpencil
•Board-approvedcalculatorsmaybeused
•Aformulaesheetisprovidedatthebackofthispaper
•WriteyourCentreNumberandStudentNumberatthetopofpages13,17,19,21,25,27and35
Total marks – 100
Section I Pages 2–11
20 marks
•AttemptQuestions1–20
•Allowabout30minutesforthissection
Section II Pages13–35
80 marks
•AttemptQuestions21–27
•Allowabout2hoursand30minutesforthissection
– 2 –
Section I
20 marksAttempt Questions 1–20Allow about 30 minutes for this section
Usethemultiple-choiceanswersheetforQuestions1–20.
1 Whichofthefollowinghasbothmagnitudeanddirection?
(A) Mass
(B) Scalar
(C) Speed
(D) Vector
2 WhichofthefollowingmethodswouldbesuitabletomanufacturePETpolymerbottles?
(A) Casting
(B) Pressing
(C) Stamping
(D) Blowmoulding
3 Amotorvehicleistravellingalongahorizontalroad.
Howdoesanincreaseinvelocityaffectitspotentialenergyandkineticenergy?
Potential energy Kinetic energy
(A) Increases Increases
(B) Maintains Increases
(C) Increases Decreases
(D) Maintains Decreases
–3–
4 Apictorialviewofablockisshown.
Front View
Whichsetofviewsrepresentstheblockinorthogonalprojection?
(A) (B)
(C) (D)
5 Theteethonasteelsprocketneedtobehard.
Sprocket teeth
Whichheattreatmentprocessismostsuitableforhardeningtheteeth?
(A) Flameheatingthenaircooling
(B) Flameheatingthenovencooling
(C) Inductionheatingthenquenching
(D) Inductionheatingthenslowcooling
– 4 –
6 Whichprocesscombinesdataandacarrierwavetoformatelevisionsignal?
(A) Compressing
(B) Encryption
(C) Modulation
(D) Multiplexing
7 Which of the lever systems would require the least force at X to balance the 100kgmass?
X100 kg
(A)
X100 kg
(C)
X100 kg
(B)
X100 kg
(D)
–5–
8 Whichstatementbestdescribesthedifferencebetweencastironandsteel?
(A) Steelcontainsmorefreegraphite.
(B) Castironhashighertensilestrength.
(C) Steelhashighercompressivestrength.
(D) Castironhasahigherpercentageofcarbon.
9 WhichformoftheACtoDCrectificationprocessisshownbythegraphs?
Before rectification
V
t
After rectification
V
t
(A) Fullwave
(B) Halfwave
(C) Smoothfullwave
(D) Smoothhalfwave
10 Theheatsinkshownisusedtoconductheatawayfromcomponents.
Heat sink
Whichrowofthetableidentifiesasuitablematerialandmanufacturingprocessfortheheatsink?
Material Manufacturing process
(A) Steel Rolling
(B) Nylon Injectionmoulding
(C) Aluminiumalloy Diecasting
(D) Ceramic Compressionmoulding
– 6 –
11 Considerthislogiccircuitforturningalamponoroff.
Switch 1
Lamp
Switch 2
Switch 3
Whichsetofconditionswillturnthelampon?
Switch 1 Switch 2 Switch 3
(A) Off Off Off
(B) On On On
(C) Off Off On
(D) Off On On
12 Eachresistorinthediagramsbelowhasavalueof10W.
Whichcombinationofresistorsprovidesatotalresistanceof15WbetweenXandY ?
(A)
(B)
(C)
(D)
X Y
X Y
X Y
X Y
–7–
13 Inwhichdirectiondoesareactionforceactatarollersupport?
(A) Paralleltothesupportingsurface
(B) Verticaltothesupportingsurface
(C) Horizontaltothesupportingsurface
(D) Perpendiculartothesupportingsurface
14 The image shows one end of an electrical spark plug used in an internal combustionengine.
M
WhichcombinationofpropertieswouldthecomponentlabelledMneedtohave?
(A) Electricalresistivityandmachinability
(B) Electricalconductivityandmachinability
(C) Electricalresistivityandtemperaturestability
(D) Electricalconductivityandtemperaturestability
– 8 –
15 Whichgraphbestrepresentstherelativeproportionsofmaterialsusedintheconstructionofnew,largepassengeraircraft?
(A) (B)
Aluminiumalloy
Composite
Titanium
Steel
Other
Composite
Aluminiumalloy
Titanium
Steel
Other
(C) (D)
Composite
Steel
Titanium
Aluminiumalloy
Other
Aluminiumalloy
Titanium
Composite
Steel
Other
–9–
16 Apoleissupportedbyfourcablesthatareattachedtoitstopandtotheslopingground.
3
34
21
2
4
1
Whichcableisshownastruelength?
(A) Cable1
(B) Cable2
(C) Cable3
(D) Cable4
17 Whichofthefollowingcouldcausefatiguecrackinginametal?
(A) Astatictensileload
(B) Asubstantialshockload
(C) Ahighcompressionload
(D) Acyclicallyappliedload
– 10 –
18 What are TWO advantages of using the powder forming process to manufacture aself-lubricatingbearing?
(A) Lowmaterialwasteandhighdensity
(B) Highporosityandlowmaterialwaste
(C) Lowdensityandhightensilestrength
(D) Highqualitysurfacefinishandhightensilestrength
19 The diagram shows one end of a universal ‘I’ beam with access holes drilled and asupportingbracketfixedtoeachside.
X
X
WhichviewshowsthecorrectfullsectionX−Xofthebeamviewedinthedirectionofthearrows?
(A) (B)
(C) (D)
– 11 –
20 Thedrawingrepresentsaloadedsteelbeamsimplysupportedateachend.
2 m 5 m 1 m
7 kN3 kN
5.1 kN 8.9 kN
UDL 500 N/m
(A)
0
(B)
0
(C)
0
(D)
0
Whichdiagrambestrepresentsthedistributionofshearforcesalongthebeam?
2 m 5 m 1 m
7 kN3 kN
5.1 kN 8.9 kN
UDL 500 N/m
(A)
0
(B)
0
(C)
0
(D)
0
–13–
CentreNumber
StudentNumber
2201
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Engineering Studies
Section II
80 marksAttempt Questions 21–27Allow about 2 hours and 30 minutes for this section
Answerthequestionsinthespacesprovided.Thesespacesprovideguidancefortheexpectedlengthofresponse.
Question 21 (11marks)
Please turn over
– 14 –
Question 21 (11marks)
(a) ThesketchshowsanearlyAustralian-builtcar.
ExplainhowTWOfeaturesofthisearlyAustralian-builtcarhavebeenmodifiedinmoderncarstoimprovetheirsafety.
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3
Question 21 continues on page 15
–15–
Question21(continued)
(b) Thediagramrepresentspartofacar’shydraulicbrakingsystem.
Brake disc
Brake caliper
Brake pedalBrake master
cylinder
Outline the operation of this hydraulic system and its advantages overmechanicalsystems.
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Question 21 continues on page 16
– 16 –
Question21(continued)
(c) Ahydrauliccylindersystemisshown.
Cylinder A has a piston area of 100mm2. Cylinder B has a piston area of700mm2.
A B
X
Y
(i) CalculatetheforceonrodYwhenaforceof50NisappliedonrodX. 2
.........................................................N
(ii) CalculatethedistancerodYwouldmovewhenrodXmoves60mm.
..................................................... mm
2
End of Question 21
©2015BoardofStudies,TeachingandEducationalStandardsNSW
–17–
CentreNumber
StudentNumber
2202
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Engineering Studies
Section II (continued)
Question 22 (12marks)
(a) Acircuitdiagramofasimpleradioreceiverisshown.
B
A
NamethecomponentslabelledAandBandoutlineeachcomponent’sfunctioninthiscircuit.
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4
(b) Howhavesemi-conductorsinfluencedthedesignofmoderntelecommunicationsproducts?
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2
Question 22 continues on page 18
– 18 –
Question22(continued)
(c) Aradioaerialsupportbracketboltedtoasteelplateisshown.Completeafullysectionedfrontviewofthebracketassembly.ApplyAS1100.
6
A A
End of Question 22
©2015BoardofStudies,TeachingandEducationalStandardsNSW
–19–
CentreNumber
StudentNumber
2203
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Engineering Studies
Section II (continued)
Question 23 (12marks)
(a) Animageofatelephonechargerisshown.
Pins
Cover
(i) Thematerialusedfortheelectricalpinsofthetelephonechargerneedstobeagoodconductorofelectricity.
List TWO other engineering properties that would be relevant whenselectingthematerialforthepins.
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2
(ii) Thetelephonechargercoveristobemanufacturedfromapolymer.
Nameanddescribeasuitablemanufacturingprocess.
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3
Question 23 continues on page 20
– 20 –
Question23(continued)
(b) Contrastthekeyfeaturesoffixedandmobiletelephonesystems.
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3
(c) A smart-phone transmits digital information. One step in this process is toconvertanaloguevoicedatatodigitiseddata.
Analogue signal
T
V
Digitised signal
T
V
4
Outlinehowananaloguesignalisdigitisedusingsamplingandquantising.
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End of Question 23
©2015BoardofStudies,TeachingandEducationalStandardsNSW
– 21 –
CentreNumber
StudentNumber
2204
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Engineering Studies
Section II (continued)
Question 24 (12marks)
(a) Thephotographshowsrailwaypowercablessupportedbyasteelcolumn.
(i) Suggestasuitablemethodthatcouldbeusedtoprotectthissteelcolumnfromcorrodingandexplainhowthismethodslowsthecorrosionprocess.
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2
(ii) Thecolumnismanufacturedbycoldrolling0.4%carbonsteel.
Sketchandlabeltheresultingmicrostructure.
2
Question 24 continues on page 22
– 22 –
Question24(continued)
(b) A diagram of a pin-jointed, cantilever truss that supports overhead railwaypowercablesisshown.
1.5 m
1.5
m
1.5 m 1.5 mCB
A
F
D E
750 N
1200 N
Aweightof1200NisdeterminedtobeactingatjointCandthepowercableweightof750NisactingatjointE.
(i) DeterminethemagnitudeofthereactionatsupportA. 2
MagnitudeofreactionatA................................N
Question 24 continues on page 23
–23–
Question24(continued)
(ii) Determine the magnitude and the direction of the reaction at the pinjointB.
3
ReactionatB.................................N Direction...................................
(iii) DeterminethemagnitudeandthenatureoftheforceinmemberAC. 3
ForceinAC.................................... N Nature.......................................
End of Question 24
–25–
CentreNumber
StudentNumber
2205
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Engineering Studies
Section II (continued)
Question 25 (12marks)
(a) Thetwoimagesshowlightaircraftpoweredbydifferentpropulsionsystems. 3
Business aircraft Recreational aircraft
Identifyasuitablepropulsionsystemforeachaircraftandjustifyyourchoice.
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(b) OutlineTWOcontroladjustmentsthatcanbemadetovarytheliftforceactingonanaircraftduringflight.
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Question 25 continues on page 26
– 26 –
Question25(continued)
(c) Anaerofoilwastestedinawindtunnel.
Thistestproducedaresultantforceof350Natanangleof10°totheliftaxis.
2
10°Air flow
Calculatethelifttodragratio.
LifttoDragRatio...............................
(d) Outline the ultrasonic testing process and its advantages for use in testingaircraftcomponents.
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End of Question 25
©2015BoardofStudies,TeachingandEducationalStandardsNSW
–27–
CentreNumber
StudentNumber
2206
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Engineering Studies
Section II (continued)
Question 26 (13marks)
Please turn over
– 28 –
Question 26 (13 marks)
(a) A winch mechanism is used to pull a 150 kg crate up a ramp and onto a transport vehicle.
25°
150 kg Ramp
Cable
Crate
Winch
The winch cable is parallel to the ramp.
(i) A simplified sketch of the crate, ramp and the tensile force (T) in the cable is shown at the point of the crate sliding up the ramp.
Add labelled arrows to the sketch to indicate the following forces:
• normal
• weight
• friction.
T
2
(ii) Calculate the tensile force in the cable at this point if the coefficient of friction between the crate and the ramp is 0.3.
3
Tension in cable ............................ N
Question 26 continues on page 29
–29–
Question26(continued)
(iii) Foradifferentsituation,thetensioninthecableis910N.Thiswinchis85%efficientandhasaneffectivedrumdiameterof100mm.
What is the minimum force (F) required to operate this winch if theeffectivelengthofthewinchhandleis350mm?
2
35
0
F
T = 910 N Ø100
Force............................................... N
Question 26 continues on page 30
–30–
Question26(continued)
(b) Thesteelusedtomanufacturethewinchcablewastestedusingatensometerandtheresultingdetailsareshownontheload−extensiongraph.
0.50
10
20
30
1 1.5
Extension (mm)
Loa
d (k
N)
2
X
Y
Z
(i) Statethesignificanceofthethreekeypointsidentifiedonthegraph. 3
X ...............................................................................................................
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Y ...............................................................................................................
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Z ...............................................................................................................
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Question 26 continues on page 31
–31–
Question26(continued)
(ii) The original gauge length of the steel test piece was 55mm with across-sectionalareaof9.6mm2.
Using data from the load−extension graph, calculate the value ofYoung’sModulusforthissteel.
3
Young’sModulus.......................................... GPa
End of Question 26
Question 27 starts on page 35
–35–
CentreNumber
StudentNumber
2207
2015 HIGHER SCHOOL CERTIFICATE EXAMINATION
Engineering Studies
Section II (continued)
Question 27 (8marks)
An engineering team consists of a civil engineer, an electrical engineer and anenvironmentalengineer.Theyhavebeencontractedbyalocalcounciltomanagethedesignandconstructionofafivemetrelongpedestrianbridgeacrossanarrowcreekinapublicpark.
Outlinehoweachof theseengineerswouldcontribute to thesuccessfulcompletionofthisproject.
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