1000+ Strength of Materials Multiple Choice Question Answer [Solved]

1. When two bodies are in thermal equilibrium with a third body, they are also in thermal equilibrium with each other. This statement is called
A. Zeroth law of thermodynamics
B. First law of thermodynamics
C. Second law of thermodynamics
D. Kelvin Planck's law
Answer : A

2. For the same maximum pressure and temperature,
A. Otto cycle is more efficient than Diesel cycle
B. Diesel cycle is more efficient than Otto cycle
C. Dual cycle is more efficient than Otto and Diesel cycles
D. Dual cycle is less efficient than Otto and Diesel cycles
Answer : B

3. Carnot cycle has maximum efficiency for
A. Petrol engine
B. Diesel engine
C. Reversible engine
D. Irreversible engine
Answer : C

4. In S. I. units, the value of the universal gas constant is
A. 8.314 J/kg mole-K
B. 83.14 J/kgmole-K
C. 831.4 J/kgmole-K
D. 8314 J/kgmole-K
Answer : D

5. When a body is subjected to a direct tensile stress (?x) in one plane accompanied by a simple shear stress (?xy), the minimum normal stress is
A. (?_x/2) + (1/2) × ?(?_x² + 4 ?²_xy)
B. (?_x/2) - (1/2) × ?(?_x² + 4 ?²_xy)
C. (?_x/2) + (1/2) × ?(?_x² - 4 ?²_xy)
D. (1/2) × ?(?x² + 4 ?²_xy)
Answer : B

6. The oxygen atom is ________ times heavier than the hydrogen atom.
A. 2
B. 8
C. 16
D. 32
Answer : C

7. The maximum tangential stress in a thick cylindrical shell is always _________ the internal pressure acting on the shell.
A. Equal to
B. Less than
C. Greater than
D. None of these
Answer : C

8. According to First law of thermodynamics,
A. Total internal energy of a system during a process remains constant
B. Total energy of a system remains constant
C. Workdone by a system is equal to the heat transferred by the system
D. Internal energy, enthalpy and entropy during a process remain constant
Answer : B

9. The stress induced in a body due to suddenly applied load compared to when it is applied gradually is
A. Same
B. Half
C. Two times
D. Four times
Answer : C

10. Which of the following is a proper sequence?
A. Proportional limit, elastic limit, yielding, failure
B. Elastic limit, proportional limit, yielding, failure
C. Yielding, proportional limit, elastic limit, failure
D. None of the above
Answer : A

11. Which of the following has the highest calorific value?
A. Peat
B. Lignite
C. Bituminous coal
D. Anthracite coal
Answer : D

12. The distillation carried out in such a way that the liquid with the lowest boiling point is first evaporated and recondensed, then the liquid with the next higher boiling point is then evaporated and recondensed, and so on until all the available liquid fuels are separately recovered in the sequence of their boiling points. Such a process is called
A. Cracking
B. Carbonisation
C. Fractional distillation
D. Full distillation
Answer : C

13. The processes occuring in open system which permit the transfer of mass to and from the system, are known as
A. Flow processes
B. Non-flow processes
C. Adiabatic processes
D. None of these
Answer : A

14. For which material the Poisson's ratio is more than unity
A. Steel
B. Copper
C. Aluminium
D. None of the above
Answer : D

15. The principal constituents of a fuel are
A. Carbon and hydrogen
B. Oxygen and hydrogen
C. Sulphur and oxygen
D. Sulphur and hydrogen
Answer : A

16. The neutral axis of a transverse section of a beam passes through the centre of gravity of the section and is
A. In the vertical plane
B. In the horizontal plane
C. In the same plane in which the beam bends
D. At right angle to the plane in which the beam bends
Answer : D

17. The distance between the centres of the rivets in adjacent rows of zigzag riveted joint is known as
A. Pitch
B. Back pitch
C. Diagonal pitch
D. Diametric pitch
Answer : C

18. Kelvin-Planck's law deals with
A. Conservation of work
B. Conservation of heat
C. Conversion of heat into work
D. Conversion of work into heat
Answer : C

19. The assumption made in Euler's column theory is that
A. The failure of column occurs due to buckling alone
B. The length of column is very large as compared to its cross-sectional dimensions
C. The column material obeys Hooke's law
D. All of the above
Answer : D

20. When a body is subjected to biaxial stress i.e. direct stresses (?_x) and (?_y) in two mutually perpendicular planes accompanied by a simple shear stress (?_xy), then maximum normal stress is
A. (?_x + ?_y)/2 + (1/2) × ?[(?_x - ?_y)² + 4 ?²_xy]
B. (?_x + ?_y)/2 - (1/2) × ?[(?_x - ?_y)² + 4 ?²_xy]
C. (?_x - ?_y)/2 + (1/2) × ?[(?_x + ?_y)² + 4 ?²_xy]
D. (?_x - ?_y)/2 - (1/2) × ?[(?_x + ?_y)² + 4 ?²_xy]
Answer : A

21. A thin mild steel wire is loaded by adding loads in equal increments till it breaks. The extensions noted with increasing loads will behave as under
A. Uniform throughout
B. Increase uniformly
C. First increase and then decrease
D. Increase uniformly first and then increase rapidly
Answer : D

22. For same compression ratio and for same heat added
A. Otto cycle is more efficient than Diesel cycle
B. Diesel cycle is more efficient than Otto cycle
C. Efficiency depends on other factors
D. Both Otto and Diesel cycles are equally efficient
Answer : A

23. The heating of gas at constant volume is governed by
A. Boyle's law
B. Charles' law
C. Gay-Lussac law
D. Avogadro's law
Answer : C

24. The ratio of root mean square velocity to average velocity of gas molecules at a particular temperature is
A. 0.086
B. 1.086
C. 1.086
D. 4.086
Answer : B

25. The extension of a circular bar tapering uniformly from diameter d? at one end to diameter d? at the other end and subjected to an axial pull of P is given by
A. ?l = 4PE/ ?l²
B. ?l = 4?ld²/PE
C. ?l = 4Pl/?Ed?d?
D. ?l = 4PlE/ ?d?d?
Answer : C

26. The change in the unit volume of a material under tension with increase in its Poisson's ratio will
A. Increase
B. Decrease
C. Remain same
D. Increase initially and then decrease
Answer : B

27. The fuel mostly used in blast furnace for extracting pig iron from iron ores is
A. Hard coke
B. Soft coke
C. Pulverised coal
D. Bituminous coal
Answer : A

28. Diesel cycle consists of __________ processes.
A. Two constant volume and two isentropic
B. Two constant pressure and two isentropic
C. Two constant volume and two isothermal
D. One constant pressure, one constant volume and two isentropic
Answer : D

29. The mass of flue gas per kg of fuel is the ratio of the
A. Mass of oxygen in 1 kg of flue gas to the mass of oxygen in 1 kg of fuel
B. Mass of oxygen in 1 kg of fuel to the mass of oxygen in 1 kg of flue gas
C. Mass of carbon in 1 kg of flue gas to the mass of carbon in 1 kg of fuel
D. Mass of carbon in 1 kg of fuel to the mass of carbon in 1 kg of flue gas
Answer : C

30. The total energy of a molecule is shared equally by the various degrees of freedom possessed by it. This law is known as
A. Law of equipartition of energy
B. Law of conservation of energy
C. Law of degradation of energy
D. None of these
Answer : A

31. The amount of heat generated per kg of fuel is known as
A. Calorific value
B. Heat energy
C. Lower calorific value
D. Higher calorific value
Answer : A

32. Coke is produced
A. When coal is first dried and then crushed to a fine powder by pulverising machine
B. From the finely ground coal by moulding under pressure with or without a binding material
C. When coal is strongly heated continuously for 42 to 48 hours in the absence of air in a closed vessel
D. By heating wood with a limited supply of air to a temperature not less than 280°C
Answer : C

33. The heat and work are mutually convertible. This statement is called __________ law of thermodynamics.
A. Zeroth
B. First
C. Second
D. Third
Answer : B

34. A riveted joint in which the number otrivets decrease from innermost to outer most rows is called
A. Chain riveted joint
B. Diamond riveted joint
C. Crisscross riveted joint
D. Zigzag riveted joint
Answer : B

35. If Kh is the torque resisting capacity of a hollow shaft and Ks is that of a solid shaft, of the same material, length and weight. Then,
A. Kh > Ks
B. Kh < Ks
C. Kh = Ks
D. None of these
Answer : A

36. The ratio of the largest load in a test to the original cross-sectional area of the test piece is called
A. Elastic limit
B. Yield stress
C. Ultimate stress
D. Breaking stress
Answer : C

37. The polytropic index (n) is given by
A. log (p₁p₂)/log (v₁v₂)
B. log (p₂/ p₁)/log (v₁/ v₂)
C. log (v₁/ v₂)/ log (p₁/p₂)
D. log [(p1v1)/(p2v2)]
Answer : B

38. The absolute zero temperature is taken as
A. 237°C
B. -273°C
C. -237°C
D. 273°C
Answer : B

39. For a beam, as shown in the below figure, the deflection at C is (where E = Young's modulus for the beam material, and I = Moment of inertia of the beam section.

A. Wl3/48 EI
B. Wa²b²/3EIl
C. [Wa/(a?3) x EIl] x (l² - a²)3/2
D. 5Wl3/384 EI
Answer : B

40. Which of the following is correct?
A. Gauge pressure = Absolute pressure + Atmospheric pressure
B. Absolute pressure = Gauge pressure + Atmospheric pressure
C. Absolute pressure = Gauge pressure - Atmospheric pressure
D. Atmospheric pressure = Absolute pressure + Gauge pressure
Answer : B

41. The state of stress at a point in a loaded member is shown in the below figure. The magnitude of maximum shear stress is

A. 10 MPa
B. 30 MPa
C. 50 MPa
D. 100 MPa
Answer : C

42. Charles' law states that all perfect gases change in volume by __________ of its original volume at 0°C for every 1°C change in temperature, when pressure remains constant.
A. 1/27th
B. 1/93th
C. 1/173th
D. 1/273th
Answer : D

43. The throttling process is __________ process.
A. Reversible
B. Irreversible
C. Reversible or irreversible
D. None of these
Answer : B

44. When it is indicated that a member is elastic, it means that when force is applied, it will
A. Not deform
B. Be safest
C. Stretch
D. Not stretch
Answer : C

45. One molecule of oxygen consists of __________ atoms of oxygen.
A. 2
B. 4
C. 8
D. 16
Answer : A

46. Which is the incorrect statement about Carnot cycle?
A. It is used as the alternate standard of comparison of all heat engines.
B. All the heat engines are based on Carnot cycle.
C. It provides concept of maximising work output between the two temperature limits.
D. All of the above
Answer : B

47. Which of the following process can be made reversible with the help of a regenerator?
A. Constant pressure process
B. Constant volume process
C. Constant pvn process
D. All of these
Answer : D

48. The ideal efficiency of a Brayton cycle with regeneration, with increase in pressure ratio will
A. Increase
B. Decrease
C. Remain unchanged
D. Increase/decrease depending on application
Answer : B

49. If the value of n = 0 in the equation pvn = C, then the process is called
A. Constant volume process
B. Adiabatic process
C. Constant pressure process
D. Isothermal process
Answer : C

50. The stress induced in a body, when suddenly loaded, is ________ the stress induced when the same load is applied gradually.
A. Equal to
B. One-half
C. Twice
D. Four times
Answer : C