51. A beam of uniform strength has at every cross-section same
a) bending moment
b) bending stress
c) deflection
d) stiffness
Ans: b
52. For no torsion, the plane of bending should
a) be parallel to one of the principal axes
b) pass through shear centre of section
c) pass through neutral axis of the section
d) pass through centre of gravity of the section
Ans: b
53. Two beams, one of circular cross-section and other of square cross-section, have equal areas of cross-section. If subjected to bending
a) circular section is more economical
b) square section is more economical
c) both sections are equally strong
d) both sections are equally stiff
Ans: b
54. The portion, which should be removed from top and bottom of a circular cross section of diameter d in order to obtain maximum section modulus, is
a) 0.01 d
b) 0.1 d
c) 0.011 d
d) 0.11 d
Ans: c
55. A beam of overall length / rests on two simple supports with equal overhangs on both sides. Two equal loads act at the free ends. If the deflection at the centre of the beam is the same as at either end, then the length of either overhang is
a) 0 152 1
b) 0.207 1
c) 0.252 1
d) 0.277 1
Ans: a
56. A beam ABC rests on simple supports at A and B with BC as an overhang. D is centre of span AB. If in the first case a concentrated load P acts at C while in the second case load P acts at D, then the
a) deflection at D in the first case will be equal to the deflection at C in the second case
b) deflection at C in the first case is equal to the deflection at D in the second case
c) deflection at D in the first case will always be smaller than the deflection at C in the second case
d) deflection at D in the first case will always be greater than the deflection at C in the second case
Ans: a
57. If the deflection at the free end of a uniformly loaded cantilever beam is 15mm and the slope of the deflection curve at the free end is 0.02 radian, then the length of the beam is
a) 0.8 m
b) lm
c) 1.2 m
d) 1.5m
Ans: b
58. If the deflection at the free end of a uniformly loaded cantilever beam of length 1 m is equal to 7.5 mm, then the slope at the free end is
a) 0.01 radian
b) 0.015 radian
c) 0.02 radian
d) none of the above
Ans: c
59. If the length of a simply supported beam carrying a concentrated load at the centre is doubled, the defection at the centre will become
a) two times
b) four times
c) eight times
d) sixteen times
Ans: c
60. A simply supported beam with rectangular cross-section is subjected to a central concentrated load. If the width and depth of the beam are doubled, then the deflection at the centre of the beam will be reduced to
a) 50%
b) 25%
c) 12.5%
d) 6.25%
Ans: d
61. A laminated spring is given an initial curvature because
a) it is more economical
b) it gives uniform strength
c) spring becomes flat when it is subjec-ted to design load
d) none of the above
Ans: c
62. A laminated spring is supported at
a) ends and loaded at centre
b) centre and loaded at ends
c) ends and loaded anywhere
d) centre and loaded anywhere
Ans: b
63. Laminated springs are subjected to
a) direct stress
b) bending stress
c) shear stress
d) none of the above
Ans: b
64. Deflection in a leaf spring is more if its
a) strength is more
b) strength is less
c) stiffness is less
d) stiffness is more
Ans: c
65. Buckling load for a given column depends upon
a) length of column only
b) least lateral dimension only
c) both length and least lateral dimension
d) none of the above
Ans: c
66. When both ends of a column are fixed, the crippling load is P. If one end of the column is made free, the value of crippling load will be changed to
a) P/16
b) P/4
c) P/2
d) 4P
Ans: a
67. Euler’s formula for a mild steel long column hinged at both ends is not valid for slenderness ratio
a) greater than 80
b) less than 80
c) greater than 180
d) greater than 120
Ans: b
68. A long column has maximum crippling load when its
a) both ends are hinged
b) both ends are fixed
c) one end is fixed and other end is hinged
d) one end is fixed and other end is free
Ans: b
69. Effective length of a chimney of 20 m height is taken as
a) 10 m
b) 20m
c) 28.28m
d) 40m
Ans: d
70. Rankine’s formula for column is valid when slenderness ratio
a) lies between 0 and 140
b) lies between 0 and 100
c) is less than 80
d) has any value
Ans: d
71. Slenderness ratio of a 5 m long column hinged at both ends and having a circular cross-section with diameter 160 mm is
a) 31.25
b) 62.5
c) 100
d) 125
Ans: d
72. The effect of arching a beam is
a) to reduce bending moment throughout
b) to increase bending moment throughout
c) to increase shear force
d) to decrease shear force
Ans: a
73. Internal forces at every cross-section in a arch are
a) nornal thrust and shear force
b) shear force and bending moment
c) normal thrust and bending moment
d) normal thrust, shear force and bending moment
Ans: d
74. According to Eddy’s theorem, the vertical intercept between the linear arch and the centre line of actual arch at any point represents to some scale
a) bending moment
b) shear force
c) normal thrust
d) deflection
Ans: a
75. Due to rise in temperature in a three hinged arch, induced stress is
a) direct compressive
b) direct tensile
c) shear
d) none of the above
Ans: d