Which of the following material is not a semiconductor ? A. Silica B. Germanium C. Selenium D. Gallium-arsenide

The number of atoms per unit cell in B.C.C. structure is_____________? A. 1B. 2 C. 4 D. 8

In a crystal, an atom vibrates at a frequency determined by_______________? A. the heat content of the crystal B. the temperature of the crystalC. the stiffness of the bonds it makes with neighbors

The conductivity of a metal is determined by____________? 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

Due to which of the following reasons aluminium does not corrode in atmosphere ? A. Aluminium is a noble metalB. Atmospheric oxygen can only diffuse very slowly through the oxide layer which is formed on the surface of aluminium C.…

The resistivity of a metal is a function of temperature because_____________? 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

Total number of crystal systems is____________? A. 2 B. 4C. 7 D. 12

A carbon resistor contains_____________? A. carbon crystals B. solid carbon granules C. pulverized coalD. finely divided carbon black

In graphite, bonding is____________? A. covalent B. metallic C. Vander WaalsD. Vander Waals and covalent

Non-linear resistors______________? A. produce harmonic distortion B. follows Ohm’s law at low temperatures only C. result in non-uniform heating D. none of the above