51. The process of mixing clay, water and other ingredients to make brick is known as
a) kneading
b) moulding
c) pugging
d) drying
Ans: a
52. Advantage of a clamp compared to a kiln for burning bricks is that
a) it takes less time for burning
b) it gives more output of first class bricks
c) it has less initial cost
d) it is suitable when bricks are required in large numbers
Ans: c
53. The internal size of mould used in brick preparation is
a) equal to the size of a fully burnt brick
b) smaller than the size of a fully burnt brick
c) greater than the size of a fully burnt brick
d) none of the above
Ans: c
54. Pug mill is used for
a) preparation of clay
b) moulding of clay
c) drying of bricks
d) burning of bricks
Ans: a
55. Which of the following bricks are used for lining of furnaces ?
a) overburnt bricks
b) underburnt bricks
c) refractory bricks
d) first class bricks
Ans: c
56. The frog of the brick in a brick masonry is generally kept on
a) bottom face
b) top face
c) shorter side
d) longer side
Ans: b
57. Number of bricks required for one cubic metre of brick masonry is
a) 400
b) 450
c) 500
d) 550
Ans: c
58. Glazing is used to make earthenware
a) hard
b) soft
c) porous
d) impervious
Ans: d
59. Quick lime is
a) calcium carbonate
b) calcium oxide
c) calcium hydroxide
d) none of the above
Ans: b
60. Quick lime is
i) slow in setting
ii) rapid in slacking
iii) good in strength
The correct answer is
a) only (i)
b) only (ii)
c) both (i) and (ii)
d) both (ii) and (iii)
Ans: c
61. Assertion A : Pure lime takes a long time to develop adequate strength.
Reason R : Pure lime has slow hardening characteristics.
Select your answer according to the coding system given below :
a) Both A and R are true and R is correct explanation of A.
b) Both A and R are true and R is not a correct explanation of A.
c) A is true but R is false.
d) A is false but R is true.
Ans: a
62. Hydraulic lime is obtained by
a) burning of lime stone
b) burning of kankar
c) adding water to quick lime
d) calcination of pure clay
Ans: b
63. The main constituent which imparts hydraulicity to hydraulic lime is
a) calcium oxide
b) silica
c) clay
d) water
Ans: c
64. Study the following statements.
i) Hydraulic lime is suitable for white washing,
ii) Fat lime is suitable for whitewashing,
iii) Hydraulic lime is suitable for making mortar,
iv) Fat lime is suitable for making mortar.
The correct answer is
a) (i) and (iv)
b) (ii) and (iii)
c) (i) and (ii)
d) (iii) and (iv)
Ans: b
65. The main ingredients of Portland cement are
a) lime and silica
b) lime and alumina
c) silica and alumina
d) lime and iron
Ans: a
66. The constituent of cement which is responsible for all the undesirable properties of cement is
a) dicalcium silicate
b) tricalcium silicate
c) tricalcium aluminate
d) tetra calcium alumino ferrite
Ans: c
67. Le Chatelier’s device is used for determining the
a) setting time of cement
b) soundness of cement
c) tensile strength of cement
d) compressive strength of cement
Ans: b
68. The main constituent of cement which is responsible for initial setting of cement is
a) dicalcium silicate
b) tricalcium silicate
c) tricalcium aluminate
d) all of the above
Ans: c
69. The initial setting time for ordinary Portland cement as per IS specifications should not be less than
a) 10 minutes
b) 30 minutes
c) 60 minutes
d) 600 minutes
Ans: b
70. As per IS specifications, the maximum final setting time for ordinary Portland cement should be
a) 30 minutes
b) 1 hour
c) 6 hours
d) 10 hours
Ans: d
71. For testing compressive strength of cement, the size of cube used is
a) 50 mm
b) 70.6 mm
c) 100 mm
d) 150 mm
Ans: a
72. The normal consistency of ordinary Portland cement is about
a) 10%
b) 20%
c) 30%
d) 40%
Ans: c
73. Early attainment of strength in rapid hardening cement is mainly due to
a) gypsum
b) finer grinding
c) tricalcium silicate
d) tricalcium aluminate
Ans: b
74. After storage, the strength of cement
a) decreases
b) increases
c) remains same
d) may increase or decrease
Ans: a
75. According to IS specifications, the compressive strength of ordinary portland cement after three days should not be less than
a) 7 MPa
b) 11.5 MPa
c) 16 MPa
d) 21 MPa
Ans: c