Strength of Materials MCQ Solved Paper for RRB JE

1. When a closely-coiled helical spring of mean diameter (D) is subjected to an axial load (W), the stiffness of the spring is given by
A. Cd?/D³n
B. Cd?/2D³n
C. Cd?/4D³n
D. Cd?/8D³n
Answer : D

2. The fuel mostly used in cement industry and in metallurgical processes is
A. Wood charcoal
B. Bituminous coke
C. Pulverised coal
D. Coke
Answer : C

3. One kg of carbon produces __________ kg of carbon dioxide.
A. 3/7
B. 7/3
C. 11/3
D. 3/11
Answer : C

4. The ratio of direct stress to volumetric strain in case of a body subjected to three mutually perpendicular stresses of equal intensity, is equal to
A. Young's modulus
B. Bulk modulus
C. Modulus of rigidity
D. Modulus of elasticity
Answer : B

5. In a tensile test, near the elastic limit zone, the
A. Tensile strain increases more quickly
B. Tensile strain decreases more quickly
C. Tensile strain increases in proportion to the stress
D. Tensile strain decreases in proportion to the stress
Answer : A

6. 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

7. The value of modulus of elasticity for mild steel is of the order of
A. 2.1 × 10? kg/cm²
B. 2.1 × 10? kg/cm²
C. 2.1 × 10? kg/cm²
D. 0.1 × 10? kg/cm²
Answer : B

8. Tensile strength of a material is obtained by dividing the maximum load during the test by the
A. Area at the time of fracture
B. Original cross-sectional area
C. Average of (A) and (B)
D. Minimum area after fracture
Answer : B

9. A cycle consisting of two adiabatic and two constant pressure processes is known as
A. Otto cycle
B. Ericsson cycle
C. Joule cycle
D. Stirling cycle
Answer : C

10. In a free expansion process,
A. W_{1 - 2} = 0
B. Q_{1 - 2} = 0
C. dU = 0
D. All of these
Answer : D

11. According to kinetic theory of gases, the velocity of molecules __________ with the increase in temperature.
A. Remains constant
B. Increases
C. Decreases
D. None of these
Answer : B

12. In an irreversible process, there is a
A. Loss of heat
B. No loss of heat
C. Gain of heat
D. No gain of heat
Answer : A

13. For the beam shown in the below figure, the shear force diagram between A and B is

A. A horizontal line
B. A vertical line
C. An inclined line
D. A parabolic curve
Answer : D

14. Kerosene is distilled at
A. 65° to 220°C
B. 220° to 345°C
C. 345° to 470°C
D. 470° to 550°C
Answer : B

15. A coil is cut into two halves, the stiffness of cut coil will be
A. Double
B. Half
C. Same
D. None of these
Answer : A

16. In a uniform bar, supported at one end in position, the maximum stress under self weight of bar shall occur at the
A. Middle of bar
B. Supported end
C. Bottom end
D. None of these
Answer : B

17. Which of the following materials is most elastic?
A. Rubber
B. Plastic
C. Brass
D. Steel
Answer : D

18. The efficiency and work ratio of a simple gas turbine cycle are
A. Very low
B. Low
C. High
D. Very high
Answer : A

19. A bar of copper and steel form a composite system, which is heated to a temperature of 40°C. The stress induced in the copper bar will be
A. Tensile
B. Compressive
C. Shear
D. Zero
Answer : B

20. An adiabatic process is one in which
A. No heat enters or leaves the gas
B. The temperature of the gas changes
C. The change in internal energy is equal to the mechanical workdone
D. All of the above
Answer : D

21. The strain energy stored in a body due to suddenly applied load compared to when it is applied gradually is
A. Same
B. Twice
C. Four times
D. Eight times
Answer : C

22. The cycle in which heat is supplied at constant volume and rejected at constant pressure is known as
A. Dual combustion cycle
B. Diesel cycle
C. Atkinson cycle
D. Rankine cycle
Answer : C

23. A definite area or a space where some thermodynamic process takes place is known as
A. Thermodynamic system
B. Thermodynamic cycle
C. Thermodynamic process
D. Thermodynamic law
Answer : A

24. In a tensile test on mild steel specimen, the breaking stress as compared to ultimate tensile stress is
A. More
B. Less
C. Same
D. More/less depending on composition
Answer : B

25. The total strain energy stored in a body is termed a
A. Resilience
B. Proof resilience
C. Modulus of resilience
D. Toughness
Answer : A

26. If the rivets in adjacent rows are staggered and the outermost row has only one rivets, the arrangement of the rivets is called
A. Chain riveting
B. Zigzag riveting
C. Diamond riveting
D. Crisscross riveting
Answer : C

27. The ratio of elongation in a prismatic bar due to its own weight (W) as compared to another similar bar carrying an additional weight (W) will be
A. 1 : 2
B. 1 : 3
C. 1 : 4
D. 1 : 2.5
Answer : B

28. The value of cp/cv for air is
A. 1
B. 1.4
C. 1.45
D. 2.3
Answer : B

29. The atomic mass of nitrogen is __________ oxygen.
A. Equal to
B. Less than
C. More than
D. None of these
Answer : B

30. A fletched beam is used to
A. Change the shape of the beam
B. Effect the saving in material
C. Equalise the strength in tension and compression
D. Increase the cross-section of the beam
Answer : C

31. 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

32. The weakest section of a diamond riveting is the section which passes through
A. The first row
B. The second row
C. The central row
D. One rivet hole of the end row
Answer : D

33. When the gas is heated at constant pressure, the heat supplied
A. Increases the internal energy of the gas
B. Increases the temperature of the gas
C. Does some external work during expansion
D. Both (B) and (C)
Answer : D

34. The maximum bending moment for the beam shown in the below figure, is

A. wl²/3?3
B. wl²/6?3
C. wl²/9?3
D. wl²/12?3
Answer : C

35. The fuel mostly used in steam boilers is
A. Brown coal
B. Peat
C. Coking bituminous coal
D. Non-coking bituminous coal
Answer : D

36. The maximum diameter of the hole that can be punched from a plate of maximum shear stress 1/4th of its maximum crushing stress of punch, is equal to (where t = Thickness of the plate)
A. t
B. 2t
C. 4t
D. 8t
Answer : C

37. A cycle consisting of __________ and two isothermal processes is known as Stirling cycle.
A. Two constant pressure
B. Two constant volume
C. Two isentropic
D. One constant pressure, one constant volume
Answer : B

38. The pressure exerted by an ideal gas is ________ of the kinetic energy of all the molecules contained in a unit volume of gas.
A. One-half
B. One-third
C. Two-third
D. Three-fourth
Answer : C

39. When the expansion or compression takes place according to the law pvn = C, the process is known as
A. Isothermal process
B. Adiabatic process
C. Hyperbolic process
D. Polytropic process
Answer : D

40. A shaft revolving at ? rad/s transmits torque (T) in Nm. The power developed is
A. T.? watts
B. 2?. T.? watts
C. 2?. T.?/75 watts
D. 2?. T.?/4500 watts
Answer : A

41. The value of gas constant (R) in S. I. units is
A. 0.287 J/kgK
B. 2.87 J/kgK
C. 28.7 J/kgK
D. 287 J/kgK
Answer : D

42. The temperature at which the volume of a gas becomes zero is called
A. Absolute scale of temperature
B. Absolute zero temperature
C. Absolute temperature
D. None of these
Answer : B

43. When a body is subjected to three mutually perpendicular stresses, of equal intensity, the ratio of direct stress to the corresponding volumetric strain is known as
A. Young's modulus
B. Modulus of rigidity
C. Bulk modulus
D. Poisson's ratio
Answer : C

44. Modulus of rigidity is defined as the ratio of
A. Longitudinal stress to longitudinal strain
B. Volumetric stress to volumetric strain
C. Lateral stress to Lateral strain
D. Shear stress to shear strain
Answer : D

45. Petrol is distilled at
A. 65° to 220°C
B. 220° to 345°C
C. 345° to 470°C
D. 470° to 550°C
Answer : A

46. The specific heat of water is
A. 1.817
B. 2512
C. 4.187
D. None of these
Answer : C

47. The amount of heat required to raise the temperature of 1 kg of water through one Kelvin is called
A. Specific heat at constant volume
B. Specific heat at constant pressure
C. kilo-Joule
D. None of these
Answer : C

48. The amount of heat required to raise the temperature of __________ water through one degree is called kilojoules.
A. 1 g
B. 10 g
C. 100 g
D. 1000 g
Answer : D

49. The point of contraflexure is a point where
A. Shear force changes sign
B. Bending moment changes sign
C. Shear force is maximum
D. Bending moment is maximum
Answer : B

50. A riveted joint in which every rivet of a row is opposite to other rivet of the outer row, is known as
A. Chain riveted joint
B. Diamond riveted joint
C. Crisscross riveted joint
D. Zigzag riveted joint
Answer : A