Civil Engineering Drawing Multiple Choice Questions on “Water Supply, Electrical and Road Work”.
1. A ___________ power supply is one that outputs hundreds or thousands of volts.
a) alternate current
b) high-voltage
c) low-voltage
d) direct current
Answer: b
Clarification: A special output connector is used that prevents arcing, insulation breakdown and accidental human contact. Federal Standard connectors are typically used for applications above 20 kV, though other types of connectors (e.g., SHV connector) may be used at lower voltages. Some high-voltage power supplies provide an analog input or digital communication interface that can be used to control the output voltage.
2. The two types of current limiting used are electronic limiting and _________________
a) inductance limiting
b) capacitor limiting
c) resistance limiting
d) impedance limiting
Answer: d
Clarification: Some supplies use current limiting instead of cutting off power if overloaded. The two types of current limiting used are electronic limiting and impedance limiting. The former is common on lab bench PSUs, the latter is common on supplies of less than 3 watts output. A foldback current limiter reduces the output current to much less than the maximum non-fault current.
3. As per IS: 1172-1963, water required per head per day for average domestic purposes, is _______
a) 120 litres
b) 135 litres
c) 75 litres
d) 195 litres
Answer: b
Clarification: For domestic purposes – 135 litres to 225 litres
For industrial purposes – 50 litres to 450 litres.
4. Most commonly used pump for lifting water in water supply mains, is _________
a) axial-flow pump
b) reciprocating pump
c) rotary type pump
d) centrifugal pump
Answer: a
Clarification: An axial flow pump, or AFP, is a common type of pump that essentially consists of a propeller in a pipe. The propeller can be driven directly by a sealed motor in the pipe or mounted to the pipe from the outside or by a right-angle drive shaft that pierces the pipe.
Fluid particles, in course of their flow through the pump, do not change their radial locations since the change in radius at the entry (called ‘suction’) and the exit (called ‘discharge’) of the pump is very small. Hence the name “axial” pump.
5. Water supply system includes ________
a) construction of dams
b) digging a well for water
c) construction of canals
d) entire arrangement from source to distribution.
Answer: d
6. In distribution pipes, drain valves are provided at __________
a) lower point
b) higher joint
c) junction points
d) anywhere
Answer: a
Clarification: The drain valve is subject to severe erosion due to the combined effect of drain discharge under high differential pressure at plant startup and the spouting of oxidized scale inside the piping.
Although drain valve have a short operating life due to their severe usage conditions, we offer a selection of drain valve with enhanced erosion resistance in an effort to increase their operating life.
7. Turbidity of raw water is a measure of ___________
a) Suspended solids
b) Acidity of water
c) B.O.D
d) Anywhere
Answer: a
Clarification: The definition of Turbidity is the cloudiness or haziness of a fluid caused by suspended solids that are usually invisible to the naked eye. The measurement of Turbidity is an important test when trying to determine the quality of water. It is an aggregate optical property of the water and does not identify individual substances; it just says something is there.
8. Disinfection of drinking water, is done to remove ___________
a) odour
b) bacteria
c) turbidity
d) colour
Answer: b
Clarification: Water disinfection means the removal, deactivation or killing of pathogenic microorganisms. Microorganisms are destroyed or deactivated, resulting in termination of growth and reproduction. When microorganisms are not removed from drinking water, drinking water usage will cause people to fall ill.
9. Aeration of water is done to remove ________
a) odour
b) colour
c) hardness
d) turbidity
Answer: a
Clarification: Aeration of liquids (usually water) is achieved by:
-passing the liquid through air by means of fountains, cascades, paddle-wheels or cones.
-passing air through the liquid by means of the Venturi tube, aeration turbines or compressed air which can be combined with diffuser(s) air stone(s), as well as fine bubble diffusers, coarse bubble diffusers or linear aeration tubing. Ceramics are suitable for this purpose, often involving dispersion of fine air or gas bubbles through the porous ceramic into a liquid. The smaller the bubbles, the more gas is exposed to the liquid increasing the gas transfer efficiency. Diffusers can also be designed into the system to cause turbulence or mixing if desired.
10. Percussion drilling is unsuitable in _______
a) unconsolidated sand
b) unconsolidated gravel
c) consolidated rocks
d) quick sand
Answer: d
Clarification: Percussion drilling is a manual drilling technique in which a heavy cutting or hammering bit attached to a rope or cable is lowered in the open hole or inside a temporary casing. The technique is often also referred to as ‘Cable tool’. Usually a tripod is used to support the tools.