Fluid Mechanics Multiple Choice Questions on “Water Hammer in Pipes”.
1. Where is a water hammer developed?
a) Reservoir
b) Penstock
c) Turbine blades
d) Pipe line
Answer: b
Clarification: Water hammer is developed in a penstock. It is developed due to the reduction in load on the generator. This reduction causes the governor to close the turbine gates and thus creating an increased pressure in the penstock.
2. Which among the following is true for hydroelectric power plants?
a) Operating cost is low and initial cost is high
b) Both operating and initial cost are high
c) Both operating and initial cost are low
d) Operating cost is high and initial cost is low
: a
Clarification: For a hydroelectric power plant, the operating cost is low and the initial cost is high. The initial cost is high due to the large area required for construction. Since, the fuel cost is comparatively cheaper, the operating cost is low.
3. The power output of the turbine in a hydroelectric plant depends on______________
a) Type of dam and its system efficiency
b) Discharge and system efficiency
c) Type of turbine and type of dam
d) Type of turbine and area of the reservoir
Answer: b
Clarification: The power output of the turbine in a hydroelectric plant depends on the system efficiency and discharge. In a hydroelectric power plant, the discharge and head are directly proportional to its system efficiency.
4. Water hammer is developed in which power plant?
a) Solar
b) Nuclear
c) Hydro
d) Wind
Answer: c
Clarification: Water hammer is defined as a pressure surge or wave caused in a pipeline. This happens due to the forceful stop of the fluid in motion. It happens mainly when the valve closes suddenly in a pipeline system. Thus, option Hydro is the right choice.
5. Which among the following are commercial sources of energy?
a) Solar energy
b) Animal wastes
c) Agricultural wastes
d) Wood
Answer: a
Clarification: Solar energy is a commercial source of energy among the following options. All energy sources that serve a commercial purpose are called as commercial sources of energy. Some good examples are Solar, tidal, wind, geothermal, wave etc.
6. Which is the most suitable place to build a hydroelectric power plant?
a) Deserts
b) Grasslands
c) Hilly areas
d) Underground
Answer: c
Clarification: Hilly areas are the most preferred areas to build a hydroelectric power plant. Hilly areas are preferred because dams play an important role. Building of dams in hilly areas is easier because large reservation can be obtained.
7. In a hydroelectric power plant, where is the penstock used?
a) Between dam and the turbine
b) Between turbine and discharge drain
c) Turbine and heat exchanger
d) Heat exchanger and fluid pump
Answer: a
Clarification: Hydroelectric powerplants play an important role in energy conversion, to produce electricity. It is a commercial method. Penstock is closed conduit. It is connected in between the dam and the turbine in the hydro station.
8. Which among the following is used as a regulating reservoir?
a) Reservoir
b) Spillways
c) Forebay
d) Penstock