APSC JE Civil Engineering 2021 PYQ with Answers । Part - 7

61 The process of passing water through beds of granular material is called

• [A] screening
• [B] sedimentation
• [C] filtration
• [D] disinfection

Correct Answer is: [C] filtration

62 The joint used for joining the plain ends of cast iron pipes is

• [A] flanged joint
• [B] socket and spigot joint
• [C] dresser coupling joint
• [D] flexible joint

Correct Answer is: [B] socket and spigot joint

63 An aquiclude is

• [A] a non-artesian aquifer
• [B] an artesian aquifer
• [C] a large water body underground
• [D] a confined bed of impervious material between aquifers

Correct Answer is: [D] a confined bed of impervious material between aquifers

64 pH 4 when compared with pH 7 will be more acidic by

• [A] 3 times
• [B] 300 times
• [C] 1000 times
• [D] 28 times

Correct Answer is: [C] 1000 times

65 Minimum DO prescribed for a river stream to avoid fish kill is

• [A] 2 ppm
• [B] 4 ppm
• [C] 8 ppm
• [D] 6.5 ppm

Correct Answer is: [B] 4 ppm

66 If organic matter increases in sewage, the demand of oxygen will

• [A] increase
• [B] decrease
• [C] remain same
• [D] sometimes increase, sometimes decrease

Correct Answer is: [A] increase

67 Composting and lagooning are the methods of

• [A] filtration
• [B] sedimentation
• [C] sludge digestion
• [D] sludge disposal

Correct Answer is: [D] sludge disposal

68 The working conditions of Imhoff tanks are

• [A] aerobic only
• [B] anaerobic only
• [C] aerobic in lower compartment and anaerobic in upper compartment
• [D] anaerobic in lower compartment and aerobic in upper compartment

Correct Answer is: [D] anaerobic in lower compartment and aerobic in upper compartment

69 Earthquake force is a function of

• [A] mass
• [B] thickness
• [C] length
• [D] breadth

Correct Answer is: [A] mass

70 The wedge-shaped bricks forming an arch ring are called

• [A] soffits
• [B] voussoirs
• [C] haunches
• [D] spandrels

Correct Answer is: [B] voussoirs