17304 - Strength of Materials

Scheme – G

Sample Question Paper Course Name : Mechanical Engineering Group Course Code : ME/PG/PT/AE/MH/MI/FE/FG Semester

: Third

17304

Subject Title : Strength Strength of Materials Marks

: 100

Time: 3 Hours

Instructions:

1. All questions are compulsory 2. Illustrate your answers with neat sketches wherever necessary 3. Figures to the right indicate full marks 4. Assume suitable data if necessary 5. Preferably, write the answers in sequential order Q1. (A) Attempt any SIX of the following

12 Marks

a) Define plasticity and stiffness.  b) Draw Core section for rectangular column. c) Write the Equation for M.I. of Hollow Shaft. d) Draw stress distribution on Rectangular s ection subjected to bending. e) State expression for Power transmitters by a shaft giving meaning of each term. . f) Define Poisons Ratio & modular of elasticity. g) What is principle stress and principle plain? h) What is meant by direct stress?

Q1. (B) Attempt any TWO of the following

08 Marks

a) A load of 5KN is to be raised with the help of a steel wire. Find the minimum diameter of the steel wire, if the stress is not to exceed 100MPa.  b) A cantilever beam 2 meter long carries a udl of 1.5 KN/m over a length of 1.6 m from the free end. Draw shear force and bending moment diagram for the beam. c) A steel wire of 5mm diameter is bend into a circular shape of 5 m radius. Determine the minimum bending stress induced in the wire. Take E=200GPa.

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Q2. Atte pt any F UR of the following

16 M rks

a) (i  Draw the ketch of st epped section showing axial load.   (ii) State the e fective len th for bot  end hinge  column.  b)

rite the ass mptions

ade in the uler’s col mn theory.

c) D aw the str  ss strain curve for duc tile material and expla n the term ultimate str ess. d) A   automob le component shown in fig no. .is subjected to a te sile load of 160 KN. Determine t e total elo gation of he compo ent, if its

odulus o   elasticity is 200GPa.

Fig no.1. e) The  princi le tensile stress s

at

a

 point across two  p rpendicula   planes ar e 80 N/m

2

2

and 4  N/mm . Find the

st esses and its obliquity on a plane at 20

 0

ormal and   tangential

wit the major  principle plane.

f) A gas cylind  r of intern l diameter 40mm is 5 m thick. f the tensile stress in the material is not to exceed 30 MPa. Find the

aximum pr essure which can be a lowed in t e cylinder.

Q3. Atte pt any F UR of the following

16 M rks

a) A simply su  ported be m of span ‘L’ is sub jected to udl of ‘w’/ nit length. Draw S.F. diagram. and B.M. diagr am.  b) A  beam AB 0 m long as support  at its ends  A and B . t carries a oint load f 5KN at 3 meters from A and a p int load o 5KN at 7 meters fro

A and a udl of 1K   per meter 

 b tween the oint loads. Draw S.F. Diagram a d B.M. dia gram for th e beam. c) A cantilever  beam 1.5

eter long s carrying  point loads  1000N ea h at a dist nce of 0.5

meter, 1.0 m ter, and 1.5 meter from the fixe  end. Dra  S.F. diagr am and B.

. diagram

for the cantil ver beam. d) A simply su  ported rig t side ov rhanging

eam supp rted at 4

eter and r ight side 1

meter overhang. A Load ed by udl 1 0 KN /m o er entire s an. Draw .F. diagra  and B.M. diagram. e) A simply su  ported bea  of 5 met r span subj ected to a lockwise a istance of 2 meter fro m the left e nd. Draw S .F. diagra

oment of 1 5 KN/m in

and B.M. iagram.

f) Find M.I. of  square 10 0 mm size  bout their iagonal.

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Q4. Atte pt any F UR of the following

16 M rks

a) Find M.I. ab ut x-x axi  of T-secti n having lange 150

m x 50 m m and web 150 mm x

5  mm, over  ll depth 20 0 mm.  b) A   I-section have the f  llowing dimensions

op flange 60 mm x 0 mm. bot tom flange

1 0 mm x 2  mm, web 100 mm x 20 mm, ov erall depth 140 mm .Find the M.I. about y-y a is. c)

n angle se tion havin dimensio s 100 mm

80 mm x 20 mm. Fi d M.I. abo t y-y axis,

w ere 100 m  side is v rtical. d) A  isosceles triangular s ection AB

has a bas width 80

m and hei ht 60 mm.  Determine

the M.I. of th e section a out c.g. of the section and the ba e BC. e)

hat is mea t by moment of resist nce and ne utral axis?

f) D aw shear s ress distribution diagr am for circ lar section and define average sh ear stress.

Q5. Atte pt any F UR of the following

a) A rectangula  beam 60

16 M rks

m wide a d 150 mm deep is sim ply supported over a s an of 6 m.

If the beam is subject d to centr al point load 12 KN , Find ma imum bending stress induced in the beam sec ion.  b) C lculate the limit of ec entricity f  r a circular  section ha ing diame er 50 mm. c) A rectangular strut is

50 mm a d 120 m   thick. It carries a l ad of 180   KN at an

eccentricity f 10 mm i  a plane bisecting the thickness. ind the m ximum an  minimum intensities of stress in th  section. d) A hallow cir  ular colu n having e xternal and  internal diameters of 300 mm a d 250 mm respectively arries a ve tical load f 100 KN t the outer edge of the column. C lculate the maximum and minimu

intensities of stress in the sectio .

e) A c-clamp as shown in ig.no 2 car ries a load P=25 KN. The cross ection of t e clamp at x-x is rectan ular, havin g width eq  al to twice the thickness. Assum ng that the c-clamp is made of steel  casing wit  allowable stress of 1 0N/ mm2. ind its di ensions. f)

A M.S. link as shown in fig.no.3 .by full li es, trans its a pull of 80 K  . Find the

dimensions b and t if  b=3t. Assu e the per  issible tensile stress as 70 MPa.

Fig no.2. 3

Fig no.3.

t

b

p

p t

Q6. Attempt any FOUR of the following

16 Marks

a) State the equation of torsion and write the notations used in it.  b) A solid circular shaft of 120 mm diameter is transmitting power of 120 KW at 150 rpm. Find the intensity of the shear stress induced in the shaft. Take Tmax =1.4 Tavg. c) Find power transmitted by a shaft having 60 mm diameter rotating at120 rpm.If maximum  permissible shear stress =80 MPa. d) A steel shaft of solid circular section has to transmit 375 KW at 210 rpm. The maximum 0

shear stress is not to exceed 50 MPa and the angle of twist must not be more than 1  in the length of 3m. Take G=80GPa.Determine diameter of the shaft. e) A shaft of hallow circular cross section has outer diameter 120 mm, inner 90 mm It is subjected to a torsional moment of 18 KN/m. For this shaft compute shear stress at the outer surface. f)

(i) Define bending stress. (ii) Define torque and state its S.I. unit.

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