Electrical Engineering Materials Multiple Choice Questions and Answers-3 (English)

1. The converse of hardness is known as
(A) malleability
(B) toughness
(C) softness
(D) none of the above
Ans: (C) softness

2. On which of the following factors does the resistivity of a material depend ?
(A) Resistance of the conductor
(B) Area of the conductor section
(C) Length of the conductor
(D) All of the above
Ans: (D) All of the above

3. is a negatively charged particle present in an atom.
(A) Proton
(B) Neutron
(C) Electron
(D) None of the above
Ans: (C) Electron

4. The formula ____ determines the number of electrons that can be accommodated in any level.
(A) 2n2
(B) 4n2
(C) 2n3
(D) 4ns
Ans: (A) 2n2

5. The tiny block formed by the arrangement of a small group of atoms is called the
(A) unit cell
(B) space lattice
(C) either (A) or (b)
(D) none of the above
Ans: (A) unit cell

6. The co-ordination number of a simple cubic structure is
(A) 2
(B) 4
(C) 6
(D) 8
Ans: (C) 6

7. The covalent bond is formed by
(A) transfer of electrons between atoms
(B) sharing of electrons between atoms
(C) sharing of variable number of electrons by a variable number of atoms
(D) none of the above
Ans: (B) sharing of electrons between atoms

8. A perfect conductor has
(A) zero conductivity
(B) unity conductivity
(C) infinite conductivity
(D) none of the above
Ans: (C) infinite conductivity

9. The metal having the lowest temperature coefficient of resistance is
(A) gold
(B) copper
(C) aluminium
(D) kanthal
Ans: (A) gold

10. Commonly used conducting materials are
(A) copper
(B) aluminium
(C) both (A) and (b)
(D) copper and silver
Ans: (C) both (A) and (b)

11. Which of the following materials is preferred for transmitting electrical energy over long distance ?
(A) Copper
(B) Aluminium
(C) Steel reinforced copper
(D) Steel reinforced aluminium
Ans: (D) Steel reinforced aluminium

12. The value of critical field below the transition temperature will
(A) increase
(B) decrease
(C) remain unchanged
(D) any of the above
Ans: (A) increase

13. In a superconductor the value of critical density depends upon
(A) magnetic field strength
(B) temperature
(C) either (A) or (b)
(D) both (A) and (b)
Ans: (D) both (A) and (b)

14. The conductors have transport phenomena of electrons due to
(A) electric field
(B) magnetic field
(C) electromagnetic field
(D) none of the above
Ans: (A) electric field

15. The transition temperature of mercury is
(A) 18.0°K
(6) 9.22°K
(C) 4.12°K
(D) 1.14’K
Ans: (C) 4.12°K

16. By increasing impurity content in the metal alloy the residual resistivity always
(A) decreases
(B) increases
(C) remains constant
(D) becomes temperature independent
Ans: (B) increases

17. The structure sensitive property of a super conductor is
(A) critical magnetic field
(B) transition temperature
(C) critical current density
(D) none of the above
Ans: (C) critical current density

18. In thermocouples which of the following pairs is commonly used ?
(A) Copper-constantan
(B) Aluminium-tin
(C) Silver-German silver
(D) Iron-steel
Ans: (A) Copper-constantan

19. ______ is an example of piezoelectric material.
(A) Glass
(B) Quartz
(C) Corrundum
(D) Neoprene
Ans: (B) Quartz

20. _____ is the main constituent of glass
(A) Fe203
(B) Si02
(C) AI2O3
(D) B2O3
Ans: (B) Si02