Electric Power Generation(Engineering > Electrical Engineering ) Questions and Answers

Question 1. A p-type semiconductor material is doped with ____________ impurities whereas a n-type semiconductor material is doped with __________ impurities
  1.    acceptor, donor
  2.    acceptor, acceptor
  3.    donor, donor
  4.    donor, acceptor
Explanation:-
Answer: Option A. -> acceptor, donor


Donor impurities denote an electron to the n-type material making it a electron majority carrier & vice-versa.



Question 2. The p-region has a greater concentration of __________ as compared to the n-region in a P-N junction.
  1.    holes
  2.    electrons
  3.    both holes & electrons
  4.    phonons
Explanation:-
Answer: Option A. -> holes


Holes are the majority charge carriers in p-type material.



Question 3. In the p & n regions of the p-n junction the _________ & the ___________ are the majority charge carriers respectively.
  1.    holes, holes
  2.    electrons, electrons
  3.    holes, electrons
  4.    electrons, holes
Explanation:-
Answer: Option C. -> holes, electrons


Holes are the majority charge carriers in p-type material & vice-versa.



Question 4. In regenerative cycle, bled steam is
  1.    discharged to atmosphere
  2.    condensed in steam condenser
  3.    used to beat feed water for boiler
  4.    is mixed with steam supplied to turbine
Explanation:-
Answer: Option C. -> used to beat feed water for boiler


used to beat feed water for boiler



Question 5. Which of the following is not the voltage at which power is usually transmitted
  1.    132 kV
  2.    66 kV
  3.    33 kV
  4.    20 kV
Explanation:-
Answer: Option D. -> 20 kV


20 kV



Question 6. Overall thermal efficiency of a steam power station is in the range
  1.    18-24%
  2.    30-40%
  3.    44-62%
  4.    68-79%
Explanation:-
Answer: Option A. -> 18-24%


18-24%



Question 7. Most of the generators in thermal power plants run at
  1.    3000 rpm
  2.    1500 rpm
  3.    1000 rpm
  4.    750 rpm
Explanation:-
Answer: Option A. -> 3000 rpm


3000 rpm



Question 8. What is the maximum size of steam turbine usually being installed, for thermal power plants ?
  1.    120 MW
  2.    250 MW
  3.    500 MW
  4.    1000 MW
Explanation:-
Answer: Option C. -> 500 MW


500 MW



Question 9. Which of the following, is not a high pressure boiler ?
  1.    Loeffler boiler
  2.    Lancashire boiler
  3.    Velox boiler
  4.    Lamont boiler
Explanation:-
Answer: Option B. -> Lancashire boiler


Lancashire boiler



Question 10. Permissible pH value of water for boilers is
  1.    1
  2.    7
  3.    slightly more than 7
  4.    10
Explanation:-
Answer: Option C. -> slightly more than 7


slightly more than 7