Laminated cores, in electrical machines, are used to reduce____________?

Related Mcqs:

1. Silicon steel is used in electrical machines because it has_____________?

   A. low coercivity B. low retentivity C. low hysteresis loss D. high coercivity...

2. Those magnetic materials are best suited for making armature and transformer cores which have ________ permeability and ________ hystersis loss

   A. high, high B. low, high C. high, low D. low, low...

3. Point out the wrong statement. Magnetic leakage is undesirable in electric machines because it___________?

   A. lowers their power efficiency B. increases their cost of manufacture C. leads to their increased weight D. produces fringing...

4. While comparing magnetic and electric circuits, the flux of magnetic circuit is compared with which parameter of electrical circuit ?

   A. E.m.f. B. Current C. Current density D. Conductivity...

5. Conductivity is analogous to____________?

   A. retentivity B. resistivity C. permeability D. inductance...

6. Hard steel is suitable for making permanent magnets because_____________?

   A. it has good residual magnetism B. its hysteresis loop has large area C. its mechanical strength is high D. its mechanical strength is low...

7. A ferrite core has less eddy current loss than an iron core because_______________?

   A. ferrites have high resistance B. ferrites are magnetic C. ferrites have low permeability D. ferrites have high hysteresis...

8. Hysteresis loss least depends on____________?

   A. volume of material B. frequency C. steinmetz coefficient of material D. ambient temperature...

9. The initial rate of rise of current through a coil of inductance 10 H when suddenly connected to a D.C. supply of 200 V is__________Vs

   A. 50 B. 20 C. 0.05 D. 500...

10. If the area of hysteresis loop of a material is large, the hysteresis loss in this material will be____________?

    A. zero B. small C. large D. none of the above...