# future- .web viewq34. if e,g and denote young’s modulus, modulus of rigidity and bulk modulus,

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Future Secure Institute

Name: SOM MM:[50],Time:[1] hours

Total Ques. [ 50 ]

Q1. Factor of safety is the ratio of:-

a) breaking stress to working stress b) endurance limit to yield stress

c) elastic limit to ultimate stress d) ultimate stress to working stress

Q2. Poisson ratio is the ratio of:-

a) lateral stress to longitudinal stress b)lateral strain to longitudinal stress

c) lateral strain to longitudinal strain d) shear stress to shear strain

Q3.select the proper sequence :-

1) proportion limit 2) elastic limit 3) yield point 4) fracture point

a) 1-2-3-4 b)2-1-3-4 c) 1-2-4-3 d)2-1-4-3

Q4.Hooks law hold good up to:-

a) yield point b) limit of proportion c) breaking point d) elastic limit

Q5. Youngs modulus (y) can also be written as:-

a) y= b) y= c) y= d)y=force x area x strain

Q6 . A 100 kg lamp is supported by a single electrical copper cable of dia 4 mm. what is the stress carried by the cable:-

a) 39mPa b) 78mPa c) 1173mPa d) 12308mPa

Q7.toughness indicate of a material :-

a)impact strength b) fatigue strength c) tensile strength d) shear strength

Q8.the value of E&G are 200GPa & 80GPa . then =- :-

a).5 b)1 c) 1.25 d) .25

Q9.the above stress strain diag is for:-

a) ductile material b) brittle material c) soft material d) none

Q10.the value of for any material cant exceed :-

a) 2 b)1.414 c) 1 d) .5

Q11.which material has the highest value of :-

a) rubber b) copper c) steel d) concrete

Q12.for a material with Poisson ratio.25, the ratio of modulus of rigidity to modulus of elasticity will be:-

a) .4 b)1.2 c)2 d) 3.6

Q13.the steel bar is elongated by the application of axial compressive load of 200 kn. Determine the elongation if the cross-section of bar is 40mm x40mm length of bar is 2m and E=200GPa:-

a) 1.25 mm b) 2.70mm c) 4.05 mm d)5.40mm

Q14.proof stress:-

a) its the safest stress

b) is that which will cause a specified permanent deformation in a material usually

c) it used in connecting with material usually

d) none

Q15.at the principle plane:-

a)the normal stress is max or min, shear stress is o

b) the tensile and compressive stress are o

c) the tensile stress is o and shear stress is max

d) None

Q16. The ratio of modulus of rigidity to modules of elasticity of a material for a Poissons ratio of.25 would be:-

a) .5 b) .4 c) .3 d).1

Q17. The capacity absorb energy when deformed elastically and then to have this energy recovered upon unloading is called:-

a) endurance b) resilience c) toughness d) ductility

Q18. A circular steel rod of 20cm cross-sectional area and 10m length is heated through 50 c with ends clamped before heating . given, E=200 GPa and coefficient of thermal expansion, =10 x 10/C, the thrust there by generated on the clamp is:-

a) 100kN b)150kN c)200kN d)250kN

Q19. The modulus of rigidity of an elastic material is found to be 38.5% of the value of its youngs modulus. The Poissons ratio of the material is nearly:-

a)0.28 b)0.30 c)0.33 d)0.35

Q20. A beam of rectangular section (12 cm wide x 20 cm deep) is simply supported over a span of 12 m. it is acted upon by a concentrated load of 80 kN at the mid span. The maximum bending stress induced is:-

a)400MPa b)300MPa c)200MPa d)100MPa

Q21.A thin cylindrical pressure vessel and a thin spherical pressure vessel have the same mean radius, same wall thickness and are subjected to same internal pressure . the hoop stresses set up in these vessels(cylinder in relation to sphere) will be in the ratio:-

a)1:2 b)1:1 c)2:1 d)4:1

Q22.A 10 mm diameter bar of mild steel of elastic modulus 200 x 10 Pa is subjected to a tensile load of 50000 N, taking it just beyond its yield point. The elastic recovery of strain that would occur upon removal of tensile load will be:-

a)1.38 x 10 b)2.68 x 10 c)3.18 x 10 d)4.62 x 10

Q23.which one of the following statements is correct?

a) the strain produced per unit volume is called resilience

b) the maximum strain produced per unit volume is called proof resilience.

c)the least strain energy stored in a unit volume is called proof resilience

d) the greatest strain energy stored in a unit volume of a material without permanent deformation is called proof resilience

Q24. The total extension of the bar loaded as shown in the figure is

A = area of cross-section

E= modulus of elasticity

a)10 x 30/AE b)26X10/AE c)9 x 30/AE d)30 x 22/AE

Q25. The deformation of a bar under its own weight as compared to that when subjected to a direct axial load equal to its own weight will be:-

a) the same b) one fourth c) half d)double

Q26. A slender bar of 100 mm cross-section is subjected to loading shown in the figure below, if the modulus of elasticity is taken as 200 x 10 Pa, then the elongation produced in the bar will be:-

a)10 mm b)5 mm c)1 mm d)nil

Q27.a straight bar is fixed at edges A and B its elastic modulus is E and cross-section is A there is a load P=120 N acting at C. the reactions at the ends are:-

a)60 N at A,60 N at B b)30N at A,90 N at B c)40 N at A,80 N at B d)80 N at A, 40 N at B

Q28. Two tapering bare of the same material are subjected to a tensile load P, the lengths of both the bars are the same. The larger diameter of each of the bars is D. the diameter of the bar B is D/3 what is the ratio of elongation of the bar A to that of the bar B?

a)3:2 b)2:3 c)4:9 d)1:3

Q29.A copper rod of 2 cm diameter is 2 cm and outer diameter 4 cm under an axial load, the stress in the tube is 100 N/mm

If Es =2 Ec then the stress in the copper rod is

a) 50 N/mm b) 33.33 N/mm c) 100N/mm d) 300 N/mm

Q30.if Poisson ratio of a material is 0.5, then the elastic modulus for the material is:-

a) three times its shear modulus b) four times its shear modulus

c) equal to its shear modulus d) indeterminate

Q31. The number of independent elastic constants required to express the stress-strain relationship for a linearly elastic isotropic material is:-

a) one b) two c) three d) four

Q32. For a given material , the modulus of rigidity is 100 GPa and Poissons ratio is 0.25. the value of modulus of elasticity in GPa is:-

a) 125 b) 150 c)200 d) 250

Q33. The modulus of elasticity for a material is 200 GN/m and Poissons ratio is 0.25. what is the modulus rigidity?

a)80GN/m b)125GN/m c) 250 GN/m d) 320 GN/m

Q34. If E,G and denote youngs modulus, modulus of rigidity and bulk modulus, respectively, for an elastic material, then which one of the following can be possible true for certain value of poissons ratio?

a)G=2K b)G=E c)K=E d) G=K=E

Q35. What is the relationship between the liner elastic properties, youngs modulus(E), rigidity modulus (G) and bulk modulus (K)?

a) = b) = c) = d) =

Q36.A rod of length/tapers uniformly from a diameter D at one end to a diameter D/2 at the other end and is subjected to an axial load P.A second rod of length/ and of uniform diameter D is subjected to the same axial load P. both the rods are of same material with youngs modulus of elasticity E. the ratio of extension of the first rod to that of the second rod is:-

a) 4 b) 3 c)2 d) 1

Q37. A beam cross-section is used in two different orientations as shown in the figure given below. bending moment applied to the beam in both cases are same, the max bending stress in case A & B are related as:-

a) A = B B) A = B C) A = D) A =

Q38. What is the nature of distribution of shear stress in a rectangular beam?

a) Linear b) Parabolic c) Hyperbolic d) Elliptic

Q39. What is the shape of the shearing stress distribution across a rectangular cross-section beam?

a) Triangular b) Parabolic only

c) rectangular only d)A combination of rectangular and parabolic shape

Q40. Match List-1 with List -2 and select