This set of Fluid Mechanics Multiple Choice Questions & Answers (MCQs) focuses on “Water Hammer in Pipes”.
1. Where is a water hammer developed?
c) Turbine blades
d) Pipe line
Explanation: 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
Explanation: 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
Explanation: 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?
Explanation: 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
Explanation: 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?
c) Hilly areas
Explanation: 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
Explanation: 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?
Explanation: Forebay serves as a regulating reservoir. It stores water on a temporary basis, during light load period. It has got an enlarged body of water situated above the intake. This intake pipe is used to store water on a temporary basis.
9. Gross head is defined as______
a) Difference of flow of object
b) Difference of flow of air
c) Difference of flow of water
d) Difference of water level between the head race and tail race
Explanation: Gross head is defined as the difference of water level between the head race (the level in storage) and the tail race. Gross head can be denoted as (H). It plays an important role in determining the power losses in the pipeline.
10. What is the function of a surge tank?
a) It causes water hammer
b) Produces surge in the pipeline
c) Relieves water hammer
d) Supplies water at constant pressure
Explanation: The main purpose of a surge tank is to relieve water hammer pressure in the penstock. It absorbs the changes in the water requirements. After absorbing the water changes, it reduces the water hammer and the negative pressure developed in the pressure stock.
11. Hydro-graph is a graph that shows________
a) Load curve
b) Energy curve
c) Mass curve
d) Volume curve
Explanation: Hydrograph is a graph that indicates the power available at different streams of water. It helps us determine the load curve. This load curve is used to determine the electrical power so developed in the hydroelectric power plant.
12. What is the function of a pump storage scheme?
a) Improve power factor
b) Improve mass factor
c) Improve plant capacity factor
d) Improve volume factor
Explanation: In a hydroelectric power plant, the main function of pump storage scheme is to make more water available during any deficiency. It strengthens the economic factor of the hydroelectric power plant.
Sanfoundry Global Education & Learning Series – Fluid Mechanics.
To practice all areas of Fluid Mechanics, here is complete set of 1000+ Multiple Choice Questions and Answers.