101. The crystal structure of silicon is
a. simple cubic
b. Body central cubic
c. Face centred cubic
d. Diamond
102. Forbidden energy gap is highest for
a. Germanium
b. Silicon
c. Galium arsenide
d. Diamond
103. Which of the following semi-conductor has the highest melting point
a. Germanium
b. Silicon
c. Galium arsenide
104. The minimum charge carried by an ion is
a. Zero
b. equal to the charge of electron
c. equal to the charge of a pair of electron
d. equal to the charge of electron left in the atom
105. The electrons in an atoms moves in
a. straight line
b. circular orbits
c. elliptical orbits
d. none of the above
106. The impurity added to extrinsic semi-conductor is of the order of
a. 1 in 100
b. 1 in 1000
c. 1 in 100,0000
d. 1 in 100,000,000
107. The mean life time of the minority carriers is in the range of a few
a. seconds
b. milli seconds
c. micro seconds
d. nano seconds
108. For insulator the energy gap is of the order of
a. 0.1 eV
b. 0.7 eV
c. 1.1 to 1.2 eV
d. 5 to 15 eV
109. Thermionic emission of electrons is due to
a. electromagnetic field
b. electrostatic field
c. high temperature
d. photo-electric effect
110. In which of the following device electron will be the majority carriers
a. p-type semi-conductor
b. N-type semi-conductor
c. N-P-N transistor
d. P-N-P transistor
