A. Silica
B. Germanium
C. Selenium
D. Gallium-arsenide
Which of the following material is not a semiconductor ? Read More »
Electrical Engineering Materials A. 1
B. 2
C. 4
D. 8
The number of atoms per unit cell in B.C.C. structure is_____________? Read More »
Electrical Engineering Materials A. the heat content of the crystal
B. the temperature of the crystal
C. the stiffness of the bonds it makes with neighbors
In a crystal, an atom vibrates at a frequency determined by_______________? Read More »
Electrical Engineering Materials A. the electronic concentration and the mobility of the free electrons
B. the number of valence electrons per atom
C. either (A) or (B)
D. none of the above
The conductivity of a metal is determined by____________? Read More »
Electrical Engineering Materials A. Aluminium is a noble metal
B. Atmospheric oxygen can only diffuse very slowly through the oxide layer which is formed on the surface of aluminium
C. No reaction with oxygen occurs ft Any of the above
Due to which of the following reasons aluminium does not corrode in atmosphere ? Read More »
Electrical Engineering Materials A. the amplitude of vibration of the atoms varies with temperature
B. the electron density varies with temperature
C. the electron gas density varies with temperature
The resistivity of a metal is a function of temperature because_____________? Read More »
Electrical Engineering Materials A. 2
B. 4
C. 7
D. 12
Total number of crystal systems is____________? Read More »
Electrical Engineering Materials A. carbon crystals
B. solid carbon granules
C. pulverized coal
D. finely divided carbon black
A carbon resistor contains_____________? Read More »
Electrical Engineering Materials A. covalent
B. metallic
C. Vander Waals
D. Vander Waals and covalent
In graphite, bonding is____________? Read More »
Electrical Engineering Materials A. produce harmonic distortion
B. follows Ohm’s law at low temperatures only
C. result in non-uniform heating
D. none of the above
Non-linear resistors______________? Read More »
Electrical Engineering Materials