61. Superposition Theorem is essentially based on the concept of
(a) Reciprocity
(b) Linearity
(c) Duality
(d) Non linearity



62. Form factor for DC supply voltage is always
(a) Zero
(b) Unity
(c) Infinity
(d) Any value between zero and one



63. In purely resistive circuits
(a) Power factor is unity
(b) Power consumed is zero
(c) Heat produced is zero
(d) Power factor is zero



64. In a series resonant circuit, the impedance below resonant frequency is
(a) Capacitive
(b) Inductive
(c) Resistive
(d) None of these



65. The figure of merit of RLC circuit will increase if
(a) R decreases
(b) R increases
(c) Voltage increases
(d) Voltage decreases



66. In an Intrinsic Semiconductor, Fermi level represents the energy with probability of its occupation of
(a) 0%
(b) 25%
(c) 50%
(d) 100%



67. An Infra Red LED is usually fabricated from
(a) Ge
(b) Si
(c) GaAs
(d) GaAsP



68. Avalanche Photo diodes are preferred over PIN diodes in optical communications system because of
(a) Speed of operation
(b) Higher sensitivity
(c) Larger bandwidth
(d) Larger power handling capacity



69. Power Transistors are invariably provided with
(a) Heat sink
(b) Metallic casing
(c) Soldered connections
(d) Fan for heat removal



70. In a JFET, beyond Pinch Off  Voltage, as the drain voltage increases, the drain current
(a) Decreases
(b) Remains constant
(c)  Increases
(d) May increase or decrease



71. After firing an SCR, if the gate pulse is removed, the SCR current
(a) Remains the same
(b) Reduces to zero
(c) Rises up
(d) Rise a little, then falls to zero



72. One of the characteristic of the Emitter Follower is its
(a) Low input resistance
(b) Low current gain
(c) Low voltage gain
(d) High output resistance



73. Cross Over Distortion I class B push pull amplifier is eliminated by
(a) Class C operation
(b) Class AB operation
(c) Elimination of output transformer
(d) Reducing transistor bias



74. A high Q tuned circuit in a tuned amplifier permits it to have high
(a) Selectivity
(b) Fidelity
(c) Sensitivity
(d) Frequency range



75. Which of the following Op-Amp system is non linear?
(a) Current to voltage convertor
(b) Logarithmic amplifier
(c) Active Filter
(d) Delay Equalizer



76. At microwave frequencies, the size of the antenna becomes
(a) Very large
(b) Large
(c) Small
(d) Very small



77. In a single phase full converter the number of SCRs conducting during overlap is
(a) 1
(b) 2
(c) 3
(d) 4



78. A sinusoidal voltage of amplitude 1 KV is amplitude modulated by another sinusoidal voltage to produce 30% modulation. The amplitude of each sideband term is
(a) 300 volts
(b) 150 volts
(c) 500 volts
(d) 250 volts



79. An interrupt in which the external device supplies its address as well as the interrupt request is known as
(a) Vectored interrupt
(b) Maskable interrupt
(c) Non-Maskable interrupt
(d) Designated interrupt



80. Logic 1 in negative logic system is represented by
(a) Zero level
(b) Lower voltage level
(c) Higher voltage level
(d) Negative voltage