Which of the following is the commonly used type of electromagnets ?

Related Mcqs:

1. The design of electromagnets is based upon which of the following fundamental equations ?

   A. Force equation B. Magnetic circuit equation C. Heating equation D. Voltage equation E. All of the above...

2. electromagnets generally function as holding magnets ?

   A. Tractive B. Portative C. Either of the above D. None of the above...

3. ____________are used for construction of core of electromagnets?

   A. Soft magnetic materials B. Hard magnetic materials C. Either A. or B. D. None of the above...

4. For large power transformers, self oil cooled type or air blast type which of the following values of current density may be used?

   A. 1.0 to 1.2 A/mm2 B. 1.5 to 2.0 A/mm2 C. 2.2 to 3.2 A/mm2 D. 3.2 to 4.2 A/mm2...

5. Multi-layer helical windings are commonly used in the transformers as high voltage windings_______________?

   A. upto 20 kV B. upto 50 kV C. upto 80 kV D. for 110 kV and above...

6. The high voltage winding is usually which of the following type ?

   A. Cylindrical winding with circular conductors B. Cross-over winding with either circular or small rectangular conductors C. Continuous disc type winding with rectangular conductors D. All of the above types...

7. ____________are always double layer type?

   A. Closed windings B. Open windings C. Either of the above D. None of the above...

8. The action of electromagnetic machines can be related to which of the following basic principles __________?

   A. Induction B. Interaction C. Alignment D. All of the above...

9. Which of the following is an advantage of hydrogen cooling ?

   A. Increase in efficiency B. Increase in ratings C. Increase in life D. Smaller size of coolers E. All of the above...

10. By which of the following methods motor rating for variable load drives can be determined ?

    A. Method of average losses B. Equivalent current method C. Equivalent torque method D. Equivalent power method E. All of the above...