51. When a normal atoms losses an electrons
a. The atom losses one proton simultaneously
b. Rest of the electron move faster
c. The atom becomes a positive ion
d. The atoms becomes a negative ion

52. Resistivity is a property of a semi-conductor that depends on
a. The atomic weight of the semi-conductor
b. The atomic number of the semi-conductor
c. The atomic nature of the semi conductor
d. The shape of the semi-conductor

53. An electrically neutral semi-conductor has
a. No free charge
b. No majority carries
c. No minority carries
d. Equal number of positive and negative charges

54. The electron in the outer most orbit is called …….. electrons
a. Valence
b. Covalent
c. Acceptor
d. Donor

55. The semi-conductors have …….. temperature coefficient resistance
a. Zero
b. Negative
c. Positive
d. Variable

56. The larger the orbit , the …… is the energy of the electron
a. Negligible
b. Lower
c. Greater
d. Infinity larger

57. In N-type semi-conductors free electrons are the ……. carriers
a. Minority
b. Majority
c. Magnetic
d. Neutral

58. The merging of a free electron and a hole is called
a. Recombination
b. Neutralization
c. Restriking
d. Zeroing

59. Excess minority carriers are the carriers that are
a. In excess of the equillibrium number
b. In excess of the number of majority carries
c. Available in impurities carries
d. Thermally generated

60. A PN-junction offers
a. High resistance in forward as well as reverse direction
b. Low resistance in forward as well as reverse direction
c. Conducts in forward direction only
d. Conducts in reverse direction only