This set of Power Plant Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Combined Cycle Plants, Nuclear and Thermionic Power Generation”.
1. The maximum steam temperature in a power cycle in degree centigrade is?
Explanation: The maximum steam temperature in a power cycle is 600 degree centigrade.
2. The temperature in a dry bottom pulverised coal furnace, in degree Celsius is about?
Explanation: The temperature in a dry bottom pulverised coal furnace, in degree Celsius is about 1300.
3. What happens to the availability in a combined cycle plant?
c) remains same
d) cannot say
Explanation: There is a great thermal irreversibility & a decrease of availability because of heat transfer from combustion gases to steam through such a large temperature difference.
4. By superposing a high temperature power plant as a topping unit to the steam plant, the energy conversion efficiency achieved is?
Explanation: By superposing a high temperature power plant as a topping unit to the steam plant, the energy conversion efficiency achieved is higher from fuel to electricity.
5. Which of the following is not a type of Combined Plant?
a) Sodium- mercury-Potassium plant
b) Gas turbine-Steam turbine plant
c) Thermionic steam plant
d) Thermoelectric steam plant
Explanation: Sodium-mercury-potassium plants have two topping fluids which is impossible for a plant to possess.
6. Which of these is not a component of nuclear reactor?
a) reactor core
c) control rod
d) biological shield
Explanation: A reflector rather than a refractor is a component of nuclear reactor.
7. Which of these is not a merit of nuclear power?
a) amount of fuel required is small
b) plant requires a huge amount of area
c) demand for coal and oil is reduced
d) most economical in large quantities
Explanation: A small amount of area is required.
8. The thermionic generator is essentially which kind of device?
a) low voltage & high current
b) high voltage & high current
c) low voltage & low current
d) high voltage and high current
Explanation: Thermionic generator is essentially a low-voltage & high-current device.
9. What efficiencies of thermionic power generator have been realised?
Explanation: Efficiency of 30-40% has been realised in thermionic generators.
10. The maximum electron current per unit area provided by an emitter is given by (where J=current density, T=absolute temperature in K, ɸ=work function in keV, k=Boltzmann’s constant & A=emission constant)
a) J= AT exp(-ɸ/kT)
b) J= AT (-ɸ/kT)
c) J= AT2 exp(-ɸ/kT)
d) J= exp(-Aɸ/kT2)
Explanation: The maximum current density is given by Richardson-Dushman equation.
11. In an electron beam, the average kinetic energy of an electron is given by
Explanation: The average kinetic energy is equal to 2KT.
Sanfoundry Global Education & Learning Series – Power Plant Engineering.
To practice all areas of Power Plant Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.