121. The bulk resistance of a diode is
a. the resistance of N material only
b. the resistance of P material only
c. the resistance of junction only
d. the resistance of P and N material
122. Which of the following can exist outside of a semi-conductor material?
a. Electrons only
b. Holes only
c. Both holes as well as electrons
d. Neither holes nor electrons
123. In case of semi conductor , recombination is
a. merging of two or more electrons
b. merging of two or more holes
c. merging of an electron with a hole
d. merging of an outside electron with semi-conductor electron
124. When a PN – junction is reverse biased
a. holes and electrons move away from the junction
b. holes and electrons move away from the junction
c. electrons and holes move towards the junction
d. depletion region decreases
125. Mobile electrons of P-side of the PN-junction diode constitute
a. majority current carriers
b. minority current carriers
c. depending upon voltage they may be either majority or minority current carriers
126. When a PN-junction is a reverse biased
a. heavy current flows in the reverse circuit
b. a very small amount of reverse current called leakage current flows
c. reverse current flow ceases
127. The depletion layer of a PN-junction diode has
a. only free mobile electrons
b. only free mobile holes
c. both free mobile holes as well as electrons
d. neither free mobile electrons nor holes
128. With the rise in temperature of a N-P junction which of the following will increase
a. width of depletion layer
b. junction barrier voltage
c. reverse leakage current
d. all of the above
129. For a PN Junction we have
a. width of depletion layer
b. junction barrier voltage
c. Reverse leakage current
130. A zener diode is invariably used with
a. forward bias
b. reverse bias
c. zero bias
