ECE 3600 Exam 1 Closed Book Questions and Answers Fully Solved Latest Version 2025-2026
What is the most energy-efficient type of common power plant? Hint: It's also one of the oldest.
ECE 3600 Exam 1 Fall 2013 - AnswersHydroelectric
Name 3 sources of electrical power for the grid which do not produce greenhouse gasses by normal
operation.
ECE 3600 Exam 1 Fall 2013 - Answers3 of these: Hydroelectric, wind, solar (steam or solar-cells), nuclear,
geothermal
Decribe how a combined-cycle, natural gas, power plant works and achieves its high efficiency?
ECE 3600 Exam 1 Fall 2013 - AnswersThe "waste" heat of a gas turbine is then used to run a steam cycle
generator.
Express power lost using the following: (Pin) and (η)
ECE 3600 Exam 1 Fall 2013 - AnswersP losses = P in - η.P in
a) Why do transformers have a maximum voltage rating?
b) That is, what bad thing are you trying to limit by limiting the voltage?
ECE 3600 Exam 1 Fall 2013 - Answersa) Core saturation
b) Insulation breakdown would happen at higher voltage
Why do transformers have a maximum current rating?
ECE 3600 Exam 1 Fall 2013 - AnswersWinding resistance & I^2*R heating
When accounting for the non-ideal characteristics of a power transformer, which of the following is the
most important (least often neglected)?
, 1.magnetization reactance
2.core losses
3.winding losses
4.leakage reactance
ECE 3600 Exam 1 Fall 2013 - Answersleakage reactance
(Look at diagram on exam)
You have a 120/40-V, 480-VA transformer. Can you use this transformer to transform 120 V to 80 V? If
yes, show the connections and compute the new VA rating.
ECE 3600 Exam 1 Fall 2013 - Answers960 VA; look at picture to confirm answer
a) How many single-phase transformers are required to transform 3-phase power. Give the minimum
number
b) Show how these single-phase transformers might be connected between the source (shown at left
below) and a load (shown at right). Do not create an unbalanced load for the source.
480, 3-Phase
Phase A
Phase B
Phase C
Neutral
c) What is the required turns ratio of the transformers you showed above. Since you don't have a
calculator, you may show a mathematical expression instead of a number.
What is the most energy-efficient type of common power plant? Hint: It's also one of the oldest.
ECE 3600 Exam 1 Fall 2013 - AnswersHydroelectric
Name 3 sources of electrical power for the grid which do not produce greenhouse gasses by normal
operation.
ECE 3600 Exam 1 Fall 2013 - Answers3 of these: Hydroelectric, wind, solar (steam or solar-cells), nuclear,
geothermal
Decribe how a combined-cycle, natural gas, power plant works and achieves its high efficiency?
ECE 3600 Exam 1 Fall 2013 - AnswersThe "waste" heat of a gas turbine is then used to run a steam cycle
generator.
Express power lost using the following: (Pin) and (η)
ECE 3600 Exam 1 Fall 2013 - AnswersP losses = P in - η.P in
a) Why do transformers have a maximum voltage rating?
b) That is, what bad thing are you trying to limit by limiting the voltage?
ECE 3600 Exam 1 Fall 2013 - Answersa) Core saturation
b) Insulation breakdown would happen at higher voltage
Why do transformers have a maximum current rating?
ECE 3600 Exam 1 Fall 2013 - AnswersWinding resistance & I^2*R heating
When accounting for the non-ideal characteristics of a power transformer, which of the following is the
most important (least often neglected)?
, 1.magnetization reactance
2.core losses
3.winding losses
4.leakage reactance
ECE 3600 Exam 1 Fall 2013 - Answersleakage reactance
(Look at diagram on exam)
You have a 120/40-V, 480-VA transformer. Can you use this transformer to transform 120 V to 80 V? If
yes, show the connections and compute the new VA rating.
ECE 3600 Exam 1 Fall 2013 - Answers960 VA; look at picture to confirm answer
a) How many single-phase transformers are required to transform 3-phase power. Give the minimum
number
b) Show how these single-phase transformers might be connected between the source (shown at left
below) and a load (shown at right). Do not create an unbalanced load for the source.
480, 3-Phase
Phase A
Phase B
Phase C
Neutral
c) What is the required turns ratio of the transformers you showed above. Since you don't have a
calculator, you may show a mathematical expression instead of a number.
