11. Which property of copper enables it to be drawn into thin wires and sheets ?
a. Ductility
b. Elasticity
c. Toughness
d. Tenacity
12. Which is non-magnetic material
a. Nickel
b. Cobalt
c. Aluminium
d. Gadolinium
13. Which of the following is the least desired property in magnetic material for electrical engineering applications
a. High magnetic permeability
b. High electrical permeability
c. Large hysteresis loop
d. All of the above
14. Above curic point
a. a ferromagnetic material becomes paramagnetic
b. a ferrite becomes an insulator
c. a insulating material becomes a ferrite
d. a diamagnetic material becomes becomes a paramagnetic material
15. For a simplex lap winding , the winding pitch is equal to
a. + 2
b. – 2
c. +- 1
d. +- 2
16. Which of the following is a paramagnetic material?
a. Palladium
b. Lead
c. Pure iron
d. All of the above
17. Which of the following is a ferromagnetic material?
a. Pure iron
b. Lead
c. Bismuth
d. Water
18. All of the following are ferromagnetic material is EXCEPT
a. Nickel
b. Bismuth
c. Silicon
d. Mild steel
19. Diamagnetic : Copper : Ferromagnetic :
a. Iron
b. Lead
c. Air
d. Water
20. Diamagnetic : Ferromagnetic :
a. Copper : Silver
b. Air : Water
c. Iron : Steel
d. Lead : Cobalt