1
Given figure shows a two stage small signal transistor feedback amplifier. Match the defective component (listed on the left hand side below) with its probable effect on the circuit (listed below)
List - $${\rm I}$$
$$A.$$ Capacitor $${C_1}$$ is open
$$B.$$ Capacitor $${C_3}$$ is open
$$C.$$ Capacitor $${C_4}$$ is open
$$D.$$ $$R{C_2}$$ is shorted
List - $${\rm II}$$
$$P.$$ All $$dc$$ voltages normal, $${V_0}$$ increases marginally
$$Q.$$ Collector of $$T{R_2}$$ at $${V_{cc}},\,\,{V_0} = 0$$
$$R.$$ All $$dc$$ voltages normal, gain of $${2^{nd}}$$ stage decreases, $${V_0}$$ decreases.
$$S.$$ All $$dc$$ voltage normal, $${V_0} = 0$$
$$T.$$ All $$dc$$ voltages normal, overall gain of the amplifier increases, $${V_0}$$ increase
$$U.$$ No change
2
Figure below shows an op-amp amplifier. Find the output voltage in steady state condition where $$(i)$$ switch is open $$(ii)$$ $$S$$ is closed
3
A practical $$R$$-$$C$$ sinusoidal oscillator is built using a positive feedback amplifier with a closed loop gain slightly less than unity.
4
In the transistor circuit shown in figure. Collector to ground voltage is $$+20V.$$ Which of the following is the probable cause of error?
5
Given figure, shows a non - inverting op - amp summer with $${V_1} = 2\,V$$ and $${V_2} = \, - 1V.$$ The output voltage $${V_0} = \_\_\_\_\_$$
6
A differentiator has transfer function whose
7
The pole $$-$$ zero configuration of a phase lead compensator is given by
8
The matrix of any state space equations for the transfer function $$C(s)/R(s)$$ of the system, shown below in. Figure is
9
The closed loop system , of Figure, is stable if the transfer function $$T\left( s \right) = {{C\left( s \right)} \over {R\left( s \right)}}$$ is stable.
10
The number of positive real roots of the equation $${s^3} - 2s + 2 = 0$$ is __________.
11
The number of comparisons carried out in a $$4$$-bit flash type $$A/D$$ converter is
12
The contents of the accumulator in an $$8085$$ microprocessor is altered after the execution of the instruction.
13
The stack pointer of a microprocessor is at $$A001H.$$ At the end of execution of following instructions, the value of stack pointer is _____________
$$\eqalign{
& PUSH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,PSW \cr
& XTHL \cr
& PUSH\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,D \cr
& JMP\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,FC70H \cr} $$
14
Figure shows $$a$$ $$b$$ $$c$$. resistive network and its graph is drawn aside. $$A$$ 'proper tree' chosen for analyzing the network will contain the edges :
15
At resonance, the given parallel circuit constituted by an iron - cored coil and a capacitor behaves like
16
In the given circuit, the voltage $$\overline {{V_L}} $$ has a phase angle of ____________ with respect to $$\overline {{V_S}} .$$
17
A set of $$3$$ equal resistors, each of value $${R_X},$$ connected in star across $$RYB$$ of given Fig. consumes the same power as the unbalanced delta-connected load shown. The value of $${R_X}$$ is _____________ $$\Omega .$$
18
If a two-port network is passive, then we have, with the usual notation, the following relationship
19
Superposition principle is not applicable to a network containing time-varying registors.
20
A precise measurement guarantees accuracy of the measured quantity.
21
A $$0$$-$$10$$ $$mA$$ $$PMMC$$ ammeter reads $$4$$ $$mA$$ in a circuit. Its bottom control spring snaps suddenly. The meter will now read nearly
22
A d.c. potentiometer is designed to measure up to about $$2$$ $$V$$ with a slide wire of $$800$$ mm. A standard cell of emf $$1.18V$$ obtains balance at $$600$$ mm. A test cell is seen to obtain balance at $$680$$ mm. The emf of the test cell is
23
A lissajous pattern, as shown in figure below, is observed on the screen of a $$CRO$$ when voltages of frequencies $${f_x}$$ and $${f_y}$$ are applied to the $$x$$ and $$y$$ plates respectively. $${f_x}:{f_y}$$ is then equal to
24
Skew is used in induction motors in order to reduce torque due to
25
When a transformers winding suffers a short-circuit, the adjoining turns of the same winding experience
26
Two transformers of identical voltage but of different capacities are operating in parallel. For satisfactory load sharing
27
Match the following List-$${\rm I}$$ with List-$${\rm II}$$
List $$-$$ $${\rm I}$$
$$(a)$$ Line charge
$$(b)$$ Magnetic Flux Density
$$(c)$$ Displacement current
$$(d)$$ Power flow
List $$-$$ $${\rm II}$$
$$(P)$$ Maxwell's
$$(Q)$$ Poynting vector
$$(R)$$ Transmission line conductors
$$(S)$$ Biot-Savart's law
$$(T)$$Gauss's law
$$(U)$$ Faraday's law
28
In electrostatic field $$\nabla\times\overrightarrow E\equiv0$$
29
Static magnetic fields induce currents in closed conducting loops.
30
$$A$$ $$\,\,5 \times 7$$ matrix has all its entries equal to $$1.$$ Then the rank of a matrix is
31
The eigen values of the matrix $$\left[ {\matrix{
a & 1 \cr
a & 1 \cr
} } \right]$$ are
32
The number of linearly independent solutions of the system of equations
$$\left[ {\matrix{
1 & 0 & 2 \cr
1 & { - 1} & 0 \cr
2 & { - 2} & 0 \cr
} } \right]\,\,\left[ {\matrix{
{{x_1}} \cr
{{x_2}} \cr
{{x_3}} \cr
} } \right] = 0$$ is equal to
33
The integration of $$\int {{\mathop{\rm logx}\nolimits} \,dx} $$ has the value
34
The volume generated by revolving the area bounded by the parabola $${y^2} = 8x$$ and the line $$x=2$$ about $$y$$-axis is
35
The directional derivative of $$f\left( {x,y} \right) = 2{x^2} + 3{y^2} + {z^2}\,\,$$ at point $$P\left( {2,1,3} \right)\,\,$$ in the direction of the vector $$\,\,a = \overrightarrow i - 2\overrightarrow k \,\,$$ is
36
A switched mode power supply operating at $$20$$ $$kHz$$ to $$100$$ $$kHz$$ range uses as the main switching element
37
A triac can be triggered by a gate pulse of __________ polarity
38
The output voltage of a six - pulse double star rectifier is the same as that of a three - phase half wave rectifier
39
Match the following
List $$-$$ $${\rm I}$$
$$A.$$ Commutation
$$B.$$ $$V$$ $$-$$ Curves
$$C.$$ Free wheeling diode
$$D.$$ Overlap
List $$-$$ $${\rm II}$$
$$P.$$ Resistive load
$$Q.$$ Inductive load
$$R.$$ Capacitive load
$$S.$$ Inter pole
$$T.$$ Source Inductance
$$U.$$ Synchronous motor
40
Referring to the figure the type of load is
41
A line - commutated inverter changes $$dc$$ voltage to $$ac$$ voltage
42
Thysistor circuits that directly convert poly phase $$ac$$ voltage from one frequency to another frequency are called _______.
43
The charging current of a $$400$$ kV transmission line is more than that of a $$220$$ kV line of the same length.
44
In a $$400$$ kV network, $$360$$ kV is recorded at a $$400$$ kV bus. The reactive power absorbed by a shunt reactor rated for $$50$$ MVAR, $$400$$ kV connected at the bus is
45
Consider a three-phase, $$50$$ $$Hz$$, $$11$$ $$kV$$ distribution system. Each of the conductors is suspended by an insulator string having two identical porcelain insulators. The self capacitance of the insulator is $$5$$ times shunt capacitance. The voltage drop across botton most disc is:
46
The increase in resistance due to non-uniform distribution of current in a conducto $$r$$ is known as _______effect
47
In a system, there are two generators operating in parallel. One generator, of rating 250 MVA, has an inertia-constant of 6 MJ/MVA while the other generator of 150 MVA has an inertia-constant of 4 MJ/MVA. The inertia-constant for the combined system on 100 MVA common base is ________MJ/MVA.
48
In a power-system, the $$3$$-phase fault MVA is always higher than the single-line-ground fault MVA at a bus (State True or False)
49
HVDC transmission is preferred to EHV __ AC because
50
If $$f(t)$$ is the step-response of a linear time-invariant system, then its impulse response is given by ___________
51
The value of the integral $$\int_{-5}^{+6}e^{-2t}\delta\left(t-1\right)dt$$ is equal to ________.