Electrical Machines Questions and Answers_pag1

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Electrical Machines Questions and 
Answers 
 
1. Questions & Answers on Magnetic Circuits 
This set of Electrical Machines Multiple Choice Questions & Answers (MCQs) focuses on 
“Principle of Energy Conversion”. 
1. An electro-mechanical energy conversion device is one which converts _______ 
a) Electrical energy to mechanical energy only 
b) Mechanical energy to electrical energy only 
c) All of the mentioned 
d) None of the mentioned 
View Answer 
Answer: c 
Explanation: The operating principles of electrical to mechanical and mechanical to electrical 
conversion devices are similar, hence, the common name electro-mechanical device.However, 
their structural details differ depending on their function. 
2. What is the coupling field used between the electrical and mechanical systems in an energy 
conversion devices? 
a) Magnetic field 
b) Electric field 
c) Magnetic field or Electric field 
d) None of the mentioned 
View Answer 
Answer: c 
Explanation: Either electric field or magnetic field can be used, however most commonly we use 
magnetic field because of its greater energy storage capacity. 
3. The energy storing capacity of magnetic field is about ________ times greater than that of 
electric field? 
a) 50,000 
b) 25,000 
c) 10,000 
d) 40,000 
View Answer 
Answer: b 
Explanation: As the energy storage capacity of the magnetic field is higher, it is most commonly 
used as coupling medium in electro-mechanical energy conversion devices. 
4. The formula for energy stored in the mechanical system of linear motion type is ______ 
a) 1/2 Jw​r​
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