Solid Mechanic
description
Transcript of Solid Mechanic
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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