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NATIOI{AL T,, TYERI'ITY OF SINGA,FONE

MEIII' - MICf,AI{IGI OT MATEnIAI.3 tr

(S.oEG 2; 4Y200{-2001

llaeAlowd: 2IIf,r

INSTRUCTIONS r() CANDInAIT'q:

!. Ttb qnLrkn pf cooi!3 F(xit (O qucdor aA cmpascs $x (O FLtt dF F '

2. Arrtrd It(tllR(O $tdd&

!. A|l $rcab.art.{d d.

a. TlbbrcumDdXcrff.

Pg,2 MElllta

Fo .h.

The follosil|g formulG writh ushg *rodad amios nry bG u!cd.

YlcH Critqtr:

(l) Trcsca Yicld Criuin

Sfrb ErcitL|:

Axid ladiDg:

BlldiE:

Tqsln:

(2) Vo Mi!.r CriEkr

'- =|t"* -"..)=?

- rg . . )

_,o_)

-'--)

u=tI1a.'ozEA

u=?!f-a62f;l

L12U= J-:-&(

62Gr

"-=|G--'-,",=iG,---" .= | (o - - ' - ,

l lfo=Et. , fr=dt, ,

G t E4l+v)

Corrfitrllvr rdrdor ftr Lotrolac &rdc lttttb:

Ir- =

6t-

ME2lla

Or6tior I

A strair glrgc fu mourt d oi s tiirFwal€d cylidricel pr.s$rc vcsscl oflhickr.ss 5 mm .tddirm.b 600 mm rs So*! in Figue l.Iflbc drrin gat3c hls t gauga Lttgth of 5 mm stdclqgrtcs 0,0(D mm wlrco o bEorl plwrc P is applic4 drtrmirc:

(a) lhc intcmrl prrsnrc P,

(10 t totb)

O) using thc trffir's cirElc for -*!it! detEiE rhr sr.xiEun ittsplte $€.ring strsinrnd dlc lerins d |t| |oSlc I t lnticlclwilc to thc r-ark.

(15 n&b)

Asru € E = 200 cPr, rad v= 0.3.

Frgp:! I

Pg3

5 rnn

ME2rr4

Ou6tior 2

A forcr P is applied to the handle AB of. contol levef, BC as shown in Figurc 2a. The lcv6is pinncd at both ends and has a cross section as shown in Figu.e 2b. It is made of stcel whichhas a yield stess in comprEssion of250 MPa- For a safety ftc'tor of I .5,

(a) det€rmine lhe maximum force P thaf can be applied so that the leve. does not buckle,

(l7 arks)

O) dctcrmine the maximuD forc€ P that cs bc applied if the length of levcr BC isshorl€ned to ,100 mm-

AssumcE=200GPa-

18 nar*s)

Fta'' 2b

Pga

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NATIONAL L]NIVERSITY OF SINGAPOREDepartment of Mechanical Engineering

Session 2003-2004, Semester [ln l)roou,"roo,,

Module Title :

Solution to Question No. Marks

anr'c n 1: --

t

(m. Y - 3ro,.',a3 -'- 2r6D //o r'\h- , )f:o.3

I D.oo a -34 =

- = o ' / r x r o

lx= t(rr- r 'ox\

0-x t vJ07 = +. %=y. >- 3 - r - ( 9 - o ' s o q )

O,+t tA - ) , tOf to \

\ Z

-'- fJ= 4oo t'|h

i.t. Cl= >ao n (a'

LnIc f,ave n-, - ?r p I 36D" J _

4 = . . : _ = ? 6 D

The ubove question hdds not been as*ed in onf preyious test ot exminatiofi papeL

saev, C5 -a7

Date:

Checked By : Date:

NA1IONAL T]NIVERSITY OF SINGA?OREDepaxtment of Mechanical Engineering

Session 2003-2004. Semester I1

Module Code:

Module Titlel

Solution lo Qu€stion No.

q) P= X= (111-yt/a

U 4= iQ- r - - ;o )- _l--, (aa6- otx'")

>dDfrcf '- 6

= t -76D{ to

.f-" -tt< t4ttr\ st-"^ cfrk- e sO"

( ., = g-ct: yL (e' = lho Vkr-x =-- J -=-

Y*'4 - -<+o ( a. ' t ' --c/"ctt ' tsP )

' Y*,r' -- 6to 4t.' J :

-+*e r?#r3 crkle\. /r^ -A!!4 = 9:: /to

-

-6- Y'"0* = t36o t to

- /.L

Als" {t"-"

The fiove question has not becn asked in on! prcvious test or examination pryer.

set By: - Date:

Checked By : Date:

Y

7

-6 tdD

/r0

k

0

- 4oo

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tad! 1660 ?@

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FACULTY OF ENGINEERINGt-g '

Course &. \ eat: .....4€?.//.ft.....

srrb jecr.................../-A.a-!:......

T_l 9

,,ll-

z r ' t + t + o + 3 z t t +

t rzo - f ? ( t

( f 63 ^^"

t + x + o L ' + = L l 1 4 X 1

zYy 36

16. Lq ""r .1

#*+J t t4x(o * Qo- r(ot)L

Q - a

o . 8 2 + * t o ' Y h " ' 1 '

/ ' 6Y l rJ ' ' - '+

-Lo * 3 z / t 43 + z z x | 4 x (tt ze'1)L

4'(< to+ ,n-?

Iot"( a><o, :t la a . + A _

:

:

-T" .lthr^t^< 9

t t6YS =

rr(8' --J =.-

J =-(o

Jcfer-,'nt lxx

f t" A,Iz_; Ar _

2 aatA r

?, Ay

I+v-At

FACULTY OF ENGINEERING

Lr Lcs<u uy,

Solution to Question No.

l . ( t '< ,or +

a . t l < r o f

4 - 6 < t o +

.T-Y \.1 -

- J

l4Pnrt

6 , 4 9 x r o

f t , / t^<o\

(.,- -F2 ET

Lz

- {r l

In,

P6bL

-kN

€,.tz- | ,Q- (x<m = f6rx an: cos+t"

o.S-oK Trtc

o. tor x d f I- 32q &/,1

T*x- = a. l t <to

co /u ,n n

- I l- L x 7noxdx 2't t<'or

Po Z-

FACULTY OF ENGINEERING. _ 3

Solution to Question No. ..........

-Frr T.s.= t . (

? , T - z t 1 e l

ch t& n - T " t -69= z t r t l l a -vcr= _F _

rlt

(= o't"\ . ! : ' = t3z-R^)l ' {

& ) $ v l = { a m n

O - -i2 y'r**,Jx z'rr/riI u t

4tnz- z € o 1 + N

. D - e 6 o * t o . l ' o ! '' F- { - .s .

= J:Jt -_ e77 4N/'r

Htnce raqxi'ru- val''e *f ( i t stA

Jwetn d bg tl4{ J,'.r,| sfr<s-r

of aro n{24 .