CONFIDENTIAL

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UNIVERSITI TUN HUSSEIN ONN MALAYSIA

FINAL EXAMINATIONSEMESTER II

SESSTON 20t0t20tl

COURSE

COURSE CODE

PROGRAMME

EXAMINATION DATE

DURATION

INSTRUCTION

SOLID MECHANICS 1

BDA IO42lBDAIMO2

BACHELOR OF MECHANICALENGINEERING WITH HONOURS

APRIL/ MAY 2OI I

3 HOURS

ANSWER FrVE (s) OUT OF SrX (6)QUESTIONS

THIS PAPER CONSIST OF SEVEN (7) PAGES

CONFIDENTIAL

BDAIO4Z BDAIO4O2

Ql FIGIIRE Ql shows a rigid beam AB suspended horizontally fiom rods C and D. Rod C

made of steel with diameter of 20 mm and rod D made of copper with diamet€r of 25 mm. Ifthe beam is to remain horizontal after the deformation ofthe rods, calculate:-

(a)

(b)

The distance.r, measured from point A where the load P could be applied (10 marks)

The str€sses that occur in the rods C and D. ifP:20 kN? (10 marks)

Given E"r : 200 GPq E* : 120 GPa

Q2 A beam ACDB is loaded with two concentrated load of 400 N as shown in FIGURE Q2.

(a)

(b)

(c)

(d)

Calculate the reaction forces at A and F.

Draw the free body diagram (FBD) of the beam.

Draw the Shearing Force Diagram (SFD) and the Bending Moment

Diagmm (BMD) of the beam.

Determine the maximum absoluk value ofthe shear and the bendins

moment.

(6 marks)

(2 marks)

(8 marks)

(4 marks)

(4 marks)

(6 marks)

(10 marks)

Q3 The horizontal bar AB of a swing s€t shown in FIGLJRE Q3 is made of steel pipe of 50 mm

inner diameter with 5 mm thickness. Two steel wires with diameter of 3 mm are also being

used to hang the swing. If the allowable stress of steel is 250 MPq compute:-

(a) The reaction force at both ends A and B.

(b) The maximum bending moment and their location

(c) What is the maximum mass of a person who may safely use the swing

with a safew factor of 4?

Q4

BDA IO4Z BDAIO4O2

A combination of solid shaft BC and hollow shaft lC is used to transmit I 2 kW power from

the motor M to a belt transmission system located at C where AC = BC as shown in

FIGLJRE Q4. The shaft is 1.5 m long with outer diameter of 40 mm and the inner diamoter

for the hollow shaft is 20 mm. The shaft is made of steel with the shear rnodulus of elasticity

is 80 GPa. The maximum speed of rotation of dre shaft is 180 rpm. The cross sectional

dimension of the belt is 5 mm and 20 mm in thickness and width respeotively. The initial

stress in the belt before the motor is in operation is 50 MPa the belt constant of elasticity is

10 kN/m and the pulley C diameter is 100 mm.

a) Determine the maximum torque at pulley C.(3 marks)

If the torque at .B is 300 Nm in direction opposite to the torque ar C find the

corresponding maximum angle oftwist ofthe shaft.

(9 marks)

Assuming no slip or creep occurs between the pulley and the belt and the change in belt

cross sectional area is negligible, determine the sfresses in the top and bottom b€lts when

the motor is operating at its maximum speed.

(8 marks)

The cap on the cylindrical tank is bolted to the tank along the flanges as in FIGIJRE Q5.

The tank has an inner diameter of 1.5 m and a wall thickness of l8 mm. Each bolt has a

diameter of 20 mm and the allowable stress for the bolts is lEO MPa. If the largest normal

saess is not to exceed 150 MPa" determine:-

b)

c)

Q5

Q6

(a)

(b)

(a)

o)

A square wooden plank with grain direction creating 15" to the vertical is subjected to the

stresses as shown in FIGIIRE Q6. By the use of plane sfress transformation equations,

determine:-

The maximum pressure the tank can sustain

The number of bolts requircd to attach the cap to the tank

Normal stress perpendicular to the grain

The shearing stress in the direction ofthe gmin

(10 marks)

(10 marks)

(10 marks)

(10 marks)

BDA 1042/ BDA10402

FINAL EXAMINATION

SEMESTEWSESSION : SEMESTER II/2010/201 |

COURSE NAME : SOLID MECHANICS I

PROGRAMME: IBDD

COURSE CODE :BD A, rc42/ BDAIO402

FIGI,JRE 01

200mm 200mm

I-l

I

I]l-

I

1.5

200 rnrn

FIGTJRE 02

BDAl04Z BDAl0,r02

FINAL EXAMINATION

SEMESTER /SESSION : SEMESTER IV20l0/201I

COURSE NAME : SOLID MECHANICS IPROGRAMME : IBDD

COURSE CODE :BD A rc4?/ BDAI04O2

FIGTJRE 03

FIGURE ()4

BDAIO42/ BDAIO4O2

FINAL EXAMINATION

SEMESTER/SESSION : SEMESTER IV20r0/201 I

COURSE NAME : SOLID MECHANICS lPROCRAMME : IBDD

COURSE CODE :BD A 1042/ BDAIO4O2

FIGURE 05

3.2 MPa

I

. 8MPa

FIGI,JRE 06

BDAIO42/ BDAlMO2

FINAL EXAMINATION

SEMESTER / SESSION : SEMESTER Il/20 I 0/20 I I

COURSE NAME : SOLID MECHANICS I

PROGRAMME : 1BDD

COURSE CODE :BDA l04Z BDA 10,102

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