SSC-JUNIOR ENGINEER (Civil & Structural) Online Exam 2019 (Part-IV)

Total Questions: 50

21. To dissipate energy a fall is provided in a canal. A fall which has gradual convex and concave curves for smooth transition of water and to reduce disturbance and impact is a:

Correct Answer: D. ogee fall
Solution:Ogee curve is the combination of convex and concave curves. So, Ogee fall consists of both convex and concave curves gradually. This gradual combination helps to provide smooth transition of flow and also reduce the impact. If the canal natural ground surface is suddenly changed to steeper slope, ogee fall is recommended for that canal. Stone pitching is provided in the upstream and downstream of the fall.

22. What is the minimum area of opening exceeding which deduction shall be made while preparing bill of quantities for roof covering and cladding?

Correct Answer: A. 0.4m²
Solution:No explanation given in the book

23. If the maximum allowable speed of a vehicle is 20 m/s and can accelerate at 0.25m/s², then what must be the radius of the circular curve and length of transition curve such that ratio of centrifugal force on vehicle to its weight is

1 : 4? (Take g = 10m m/s² )

Correct Answer: A. 160 m, 200 m
Solution:

24. The minimum length of intermittent fillet weld shall be:

Correct Answer: B. 40 mm or four times the size of weld
Solution:Intermittent welds: Length shall not be less than 4 times the weld size or 40 mm whichever is more. The minimum clear spacing of intermittent weld shall be 12t for compression joints and 16t for tensile joints where t is the thickness of thinner plate joined. The intermittent welds shall not be used in positions subject to dynamic, repetitive and alternating stresses.

25. What must be radius of a circular curve for railway of chord length 30 m, where the degree of curvature is 2°?

Correct Answer: A. 860 m
Solution:

26. Which of the following is NOT correct about the effects of compaction of soil?

Correct Answer: B. Compaction increases the permeability of soil.
Solution:Compaction reduces the voids present in the soil hence permeability also reduces. At a particular density, for the same soil sample, permeability is more for soils which are compacted to dry of optimum than those compacted to wet of optimum.

27. Two cars are moving in the opposite direction with speeds 25 m/s and 20 m/s respectively. If total reaction time is 2.5 seconds and design coefficient of friction is 0.35, then what must be the minimum sight distance to avoid head on collision? (Take g = 10 m/s²)

Correct Answer: A. 258.93 m
Solution:

28. For a pipe of diameter 1 m when running full, the hydraulic mean depth will be:

Correct Answer: A. 0.25 m
Solution:

29. In which of the following systems of water distribution, water can reach a particular point only through one route and any damage or repairs at a point in the pipe line will completely stop the water supply in the area being fed by that pipe beyond the point of damage or repairs?

Correct Answer: B. Dead-end system
Solution:Dead End System
  • This system is also known as tree system.
  • In this system, one main pipe from which a number of submains bifurcate and from each submains several branched pipes separate out which are known as laterals.
  • It has got draw backs that water can reach at a particular point only through one route, hence, if some fault creep in, water supply get disturbed in that area because water conveyance is unidirectional only.
  • There are many dead ends which prevent free circulation of water.
  • In this system, stagnant water has to be removed periodically by providing scour valves at dead ends and this results in wastage of treated water.

30. Which of the following is a positive displacement pump?

Correct Answer: D. Reciprocating pump
Solution:A reciprocating pump is a class of positive-displacement pumps that includes the piston pump, plunger pump, and diaphragm pump. It is often used where a relatively small quantity of liquid is to be handled and where delivery pressure is quite large. In reciprocating pumps. the chamber that traps the liquid is a stationary cylinder that contains a piston or plunger.