Materials for electrical equipments - Electrical Engineering (MCQ) questions and answers

1)   What is the purity of electrically graded aluminium?

a. 95 %
b. 98.3 %
c. 99.5 %
d. 97.5 %
Answer  Explanation 

ANSWER: 99.5 %

Explanation:
No explanation is available for this question!


2)   Which material can be used upto a temperature of 130° C?

a. Mica
b. Cotton
c. Synthetic resin
d. All of these
Answer  Explanation 

ANSWER: Mica

Explanation:
No explanation is available for this question!


3)   Which alloy is used as electrical resistance alloy?

a. Nickel alloys
b. Nickel chromium alloys
c. Ferro nickel alloys
d. Only a and b
e. All of these
Answer  Explanation 

ANSWER: All of these

Explanation:
No explanation is available for this question!


4)   Which among these materials is a permanent magnetic material?

a. Palladium
b. Chromium steel
c. Silicon steel
d. All of these
Answer  Explanation 

ANSWER: Chromium steel

Explanation:
No explanation is available for this question!


5)   Which among these is a method to minimise eddy current loss?

a. Laminated core
b. Insulation of lamination
c. Use of material of high electrical resistivity
d. Only a and c
e. All of these
Answer  Explanation 

ANSWER: All of these

Explanation:
No explanation is available for this question!


6)   Which material has a lower dielectric strength at 50 Hz?

a. Bakelite
b. Glass
c. Air
d. Dielectric oil
Answer  Explanation 

ANSWER: Air

Explanation:
No explanation is available for this question!


7)   Which among these materials have a relative permeability of 1?

i. Air
ii. Copper
iii. Iron
iv. Nickel


a. i and ii only
b. i and iii only
c. i and iv only
d. iii and iv only
Answer  Explanation 

ANSWER: i and ii only

Explanation:
No explanation is available for this question!


8)   Which material is used as a conducting material in electrical machines?

i. Copper
ii. Aluminium
iii. Nickel
iv. Iron


a. i, iii and iv
b. ii and iv only
c. i and ii only
d. i and iv only
Answer  Explanation 

ANSWER: i and ii only

Explanation:
No explanation is available for this question!


9)   For which among these applications is porcelain used?

i. Enclosure for CTs and circuit breakers
ii. Enclosure for large indoor transformers
iii. Enclosure for bushing
iv. Support for bus bars


a. i and ii only
b. ii, iii and iv only
c. i, iii and iv only
d. i, ii, iii and iv
Answer  Explanation 

ANSWER: i, iii and iv only

Explanation:
No explanation is available for this question!


10)   Which properties should a material posse so as to be used for electrical equipments?

i. High resistance
ii. High luminosity
iii. Fire retarding insulation
iv. High permittivity


a. i and ii only
b. i and iv only
c. i, iii and iv
d. All of these
Answer  Explanation 

ANSWER: All of these

Explanation:
No explanation is available for this question!