Problem-0111: Electrical Materials objective question
Thu, 27/01/2011 - 9:13pmMatch List-I with List-II and select the correct answer using the code given below the lists:
Electrical Materials
Problem-0120: Electrical Materials objective question
Thu, 27/01/2011 - 9:07pmWhich one of the following is the correct statement?
During the process of magnetization of ferromagnetic material, the magnetic domains
a. Only expand
b. Rotate first and then expand
c. Expand first and then rotate
d. Neither rotate nor expand
Problem-0118: Electrical Materials objective question
Thu, 27/01/2011 - 9:05pmConsider the following statements about p-n junctions:
1. p-n junction behaves as a capacitor when forward biased.
2. p-n junction has p and n type semiconductors with depletion layer in between.
Problem-0117: Electrical Materials objective question
Thu, 27/01/2011 - 9:00pmWhich one of the following is the correct statement?
When a p-n junction is reverse-biased,then
a. Holes and electrons move away from the junction
b. Depletion region decreases
c. Barrier breaks down
d. Minority carriers are not affected
Problem-0116: Electrical Materials objective question
Thu, 27/01/2011 - 8:58pmConsider the following statements about semiconductors?
1. The forbidden energy gap in semiconductors lies between the valence band and conduction band.
2. The forbidden energy gap in germanium at 0 K is about 0.72 eV.
Problem-0115: Electrical Materials objective question
Thu, 27/01/2011 - 8:38pmFermi level in a p-type semiconductor lies close to which one of the following?
a. The top of the valence band
b. The bottom of the valence band
c. The top of the conduction band
d. The bottom of the conduction bond
Problem-0119: Electrical Materials objective question
Thu, 27/01/2011 - 8:37pmWhich one of the following is the correct statement?
The type of majority charge carriers in a semiconductor can be found by
a. Hall effect
b. Piezoelectric effect
c. Photoelectric effect
d. Meissner effect
Problem-0110: Electrical Materials objective question
Thu, 27/01/2011 - 8:33pmMaterials which lack permanent magnetic dipoles are known as:
a. Paramagnetic
b. Diamagnetic
c. Ferromagnetic
d. Ferrimagnetic
Problem-0109: Electrical Materials objective question
Thu, 27/01/2011 - 8:31pmWhy is the core of the transformer built up of lamination?
a. To reduce eddy current loss
b. For convenience of fabrication
c. No specific advantage
d. For increasing the permeability
Problem-0064: Electrical Materials objective question
Thu, 27/01/2011 - 2:45pmTwo materials having temperature coefficient of 0.004 and 0.004 respectively are joined in series. The overall temperature coefficient is approximately:
a. 0.08
b. 0.04
c. 0.001
d. 0.0001