An operational-amplifier circuit is shown in the figure.

The output of the circuit for a given input $${V_i}$$ is

A hysteresis type $$TTL$$ inverter is used to realize an oscillator in the circuit shown in the figure.

If the lower and upper trigger level voltages are $$0.9$$ $$V$$ and $$1.7$$ $$V,$$ the period (in $$ms$$), for which output is LOW, is ____________.

The transfer characteristic of the Op-amp circuit shown in figure is

A single-input single-output feedback system has forward transfer function $$𝐺(𝑠)$$ and feedback transfer function $$𝐻(𝑠).$$ It is given that $$\left| {G\left( s \right)H\left( s \right)} \right| < 1.$$ Which of the following is true about the stability of the system?

The signal flow graph of a system is shown below. $$U(S)$$ is the input and $$C(S)$$ is the output.

Assuming $${h_1} = {b_1}$$ and $${h_0} = {b_0} - {b_1}{a_1},$$ the input-output transfer function, $$G\left( S \right) = {{C\left( S \right)} \over {U\left( S \right)}}$$ of the system is given by

The block diagram of a system is shown in the figure

If the desired transfer function of the system is $${{C\left( s \right)} \over {R\left( s \right)}}\, = {s \over {{s^2} + s + 1}},$$ then $$G(s)$$ is

The magnitude Bode plot of a network is shown in the figure

The maximum phase angle $${\phi _m}$$ and the corresponding gain $${G_m}$$ respectively are

Consider the system described by the following state space equations $$$\eqalign{ & \left[ {\matrix{ {{x_1}} \cr {{x_2}} \cr } } \right] = \left[ {\matrix{ 0 & 1 \cr { - 1} & { - 1} \cr } } \right]\left[ {\matrix{ {{x_1}} \cr {{x_2}} \cr } } \right] + \left[ {\matrix{ 0 \cr 1 \cr } } \right]u; \cr & y = \left[ {\matrix{ 1 & 0 \cr } } \right]\left[ {\matrix{ {{x_1}} \cr {{x_2}} \cr } } \right] \cr} $$$

If $$u$$ unit step input, then the steady state error of the system is

Two monoshot multivibrators, one positive edge triggered $$\left( {{M_1}} \right)$$ and another negative edge triggered $$\left( {{M_2}} \right)$$ are connected as shown in figure.

The monoshots $${{M_1}}$$ and $${{M_2}}$$ when triggered produce pulses of width $${{T_1}}$$ and $${{T_2}}$$ respectively, where $${T_1} > {T_2}.$$ The steady state output voltage $${V_0}$$ of the circuit is

A $$3$$-bit gray counter is used to control the output of the multiplexer as shown in the figure. The initial state of the counter is $${000_2}.$$ The output is pulled high. The output of the circuit follows the sequence

A state diagram of a logic gate which exhibits a delay in the output is shown in the figure, where $$X$$ is the don't care condition, and $$Q$$ is the output representing the state.

The logic gate represented by the state diagram is

In $$8085A$$ microprocessor, the operation performed by the instruction $$LHLD$$ $${2100_H}$$ is

The Norton’s equivalent source in amperes as seen into the terminals X and Y is _______.

A non-ideal voltage source V_S has an internal impedance of Z_S. If a purely resistive load is to be chosen that maximizes the power transferred to the load, its value must be

A series RLC circuit is observed at two frequencies. At $$\omega_1$$ = 1k rad / s, we note that source voltage $$V_1=100\angle0^\circ V$$ results in a current $$I_1=0.03\angle31^\circ\;A$$. At $$\omega_2$$ = 2 k rad/s, the source voltage $$V_2=100\angle0^\circ\;V$$ results in a current $$I_2=2\angle0^\circ\;A$$. The closest values for R,L,C out of the following options are

The line A to neutral voltage is $$10\angle15^\circ\;V$$ for a balanced three phase star-connected load with phase sequence ABC. The voltage of line B with respect to line C is given by

The driving point impedance Z(s) for the circuit shown below is

The power delivered by the current source, in the figure, is ________ W.

A periodic waveform observed across a load is represented by $$$V\left( t \right) = \left\{ {\matrix{ {1 + \sin \,\omega t} & {0 \le \omega t < 6\pi } \cr { - 1 + \sin \,\omega t} & {6\pi \le \omega t < 12\pi } \cr } } \right.$$$
$$6\pi \le \omega t < 12\,\pi $$
The measured value, using moving iron voltmeter connected across the load, is

In the bridge circuit shown, the capacitors are loss free. At balance, the value of capacitance C₁ in microfarad is ________.

An $$LPF$$ wattmeter of power factor $$0.2$$ is having three voltage settings $$300V,$$ $$150V$$ and $$75V,$$ and two current settings $$5 A$$ and $$10A.$$ The full scale reading is $$150.$$ If the wattmeter is used with $$150V$$ voltage setting and $$10A$$ current setting, the multiplying factor of the wattmeter is __________.

The two signals $$S1$$ and $$S2,$$ shown in figure, are applied to $$Y$$ and $$X$$ deflection plates of an oscilloscope.

The waveform displayed on the screen is

A non-salient pole synchronous generator having synchronous reactance of $$0.8$$ $$pu$$ is supplying $$1$$ $$pu$$ power to a unity power factor load at a terminal voltage of $$1.1$$ $$pu$$. Neglecting the armature resistance, the angle of the voltage behind the synchronous reactance with respect to the angle of the terminal voltage in degrees is ____________.

The no-load speed of a 230 V separately excited dc motor is 1400 rpm. The armature resistance drop and the brush drop are neglected. The field current is kept constant at rated value. The torque of the motor in Nm for an armature current of 8 A is ____________.

A separately excited 300 V DC shunt motor under no load runs at 900 rpm drawing an armature current of 2 A. The armature resistance is 0.5 $$\Omega$$ and leakage inductance is 0.01 H. When loaded, the armature current is 15 A. Then the speed in rpm is _____

The mean thickness and variance of silicon steel laminations are 0.2 mm and 0.02 respectively. The varnish insulation is applied on both the sides of the laminations. The mean thickness of one side insulation and its variance are 0.1 mm and 0.01 respectively. If the transformer core is made using 100 such varnish coated laminations, the mean thickness and variance of the core respectively are

The parameters measured for a 220V/110V, 50 Hz, single-phase transformer are:

Self inductance of primary winding = 45 mH
Self inductance of secondary winding = 30 mH
Mutual inductance between primary and secondary windings = 20 mH

Using the above parameters, the leakage (L_l1 , L_l2) and magnetizing (L_m) inductances as referred to primary side in the equivalent circuit respectively, are

An open circuit test is performed on 50 Hz transformer, using variable frequency source and keeping V/f ratio constant, to separate its eddy current and hysteresis losses. The variation of core loss/frequency as function of frequency is shown in the figure The hysteresis and eddy current losses of the transformer at 25 Hz respectively are

The load shown in the figure absorbs 4 kW at a power factor of 0.89 lagging. Assuming the transformer to be ideal, the value of the reactance X to improve the input power factor to unity is ___________.

A single phase induction motor is provided with capacitor and centrifugal switch in series with auxiliary winding. The switch is expected to operate at a speed of 0.7 Ns, but due to malfunctioning the switch fails to operate. The torque-speed characteristic of the motor is represented by

The torque-speed characteristics of motor ($$T_M$$) and load ($$T_L$$) for two cases are shown in the figures (a) and (b). The load torque is equal to motor torque at points P, Q, R and S The stable operating points are

In a synchronous machine, hunting is predominantly damped by

A hollow metallic sphere of radius r is kept at potential of 1 Volt. The total electric flux coming out of the concentric spherical surface of radius R(>r) is

A perfectly conducting metal plate is placed in x-y plane in a right handed coordinate system. A charge of $$+32{\mathrm{πε}}_0\sqrt2$$ columbs is placed at coordinate (0, 0, 2). $${\mathrm\varepsilon}_0$$ is the permittivity of free space. Assume $$\widehat i,\;\widehat j,\;\widehat k$$ to be unit vectors along x, y and z axes respectively. At the coordinate $$\left(\sqrt2,\sqrt2,0\right)$$, the electric field vector $$\overrightarrow E$$ (Newtons/Columb) will be

The function $$f\left( x \right) = {e^x} - 1\,\,$$ is to be solved using Newton $$-$$ Raphson method. If the initial value of $${x_0}$$ is taken $$1.0,$$ then the absolute error observed at $${2^{nd}}$$ iteration is ___________.

Integration of the complex function $$f\left( z \right) = {{{z^2}} \over {{z^2} - 1}},$$ in the counterclockwise direction, around $$\left| {z - 1} \right| = 1,$$ is

$$A = \left[ {\matrix{ p & q \cr r & s \cr } } \right];B = \left[ {\matrix{ {{p^2} + {q^2}} & {pr + qs} \cr {pr + qs} & {{r^2} + {s^2}} \cr } } \right]$$
If the rank of matrix $$A$$ is $$N$$, then the rank of matrix $$B$$ is

A particle, starting from origin at $$t=0$$ $$s,$$ is traveling along $$x$$-axis with velocity $$v = {\pi \over 2}\cos \left( {{\pi \over 2}t} \right)m/s$$
At $$t=3$$ $$s,$$ the difference between the distance covered by the particle and the magnitude of displacement from the origin is _________.

Let $$\,\,\nabla .\left( {fV} \right) = {x^2}y + {y^2}z + {z^2}x,\,\,$$ where $$f$$ and $$V$$ are scalar and vector fields respectively. If $$V=yi+zj+xk,$$ then $$\,V.\left( {\nabla f} \right)$$ is

Lifetime of an electric bulb is a random variable with density $$f\left( x \right) = k{x^2},$$ where $$x$$ is measured in years. If the minimum and maximum lifetimes of bulb are $$1$$ and $$2$$ years respectively, then the value of $$k$$ is ________.

A three-phase fully controlled bridge converter is fed through star-delta transformer as shown in the figure.

The converter is operated at a firing angle of $${30^0}.$$ Assuming the load current $$\left( {{{\rm I}_0}} \right)$$ to be virtually constant at $$1$$ $$p.u.$$ and transformer to be an ideal one, the input phase current waveform is

A diode circuit feeds an ideal inductor as shown in the figure. Given $${V_s} = 100\,\,\sin \,\left( {\omega t} \right)V,$$ where $$\omega = 100\pi $$ rad/s, and $$L=31.83$$ $$mH$$. The initial value of inductor current is zero. Switch $$S$$ is closed at $$t=2.5$$ $$ms.$$ The peak value of inductor current $${i_L}\left( {in\,\,A} \right)$$ in the first cycle is __________.

A single - phase voltage source inverter shown in figure is feeding power to load. The triggering pulses of the devices are also shown in the figure.

If the load current is sinusoidal and is zero at $$0,\,\,\pi ,2\pi ....,$$ the node voltage $${V_{AO}}$$ has the waveform

In a long transmission line with $$r, l, g$$ and $$𝑐$$ are the resistance, inductance, shunt conductance and capacitance per unit length respectively, the condition for distortionless transmission is

For a $$400$$ $$km$$ long transmission line, the series impedance is $$(0.0 + j0.5)$$ $$\Omega /km$$ and the shunt admittance is $$(0.0 + j5.0)$$ $$\mu \,mho/km.$$ The magnitude of the series impedance (in $$\Omega $$) of the equivalent $$\pi $$ circuit of the transmission line is __________.

The complex power consumed by a constant-voltage load is given by $$\left( {{P_1} + {J_{q1}}} \right).\,\,$$ Where, $$\,1\,\,kW \le \,\,{P_1} \le \,\,\,1.5\,\,kW\,\,\,$$ and $$\,\,0.5\,KVAR \le \,\,\,{Q_1} \le 1kVAR.\,\,\,$$ A compensating shunt capacitor is chosen such that $$\,\left| Q \right| \le 0.25\,\,KVAR,\,\,$$ where $$Q$$ is the net reactive power consumed by the capacitor-load combination. The reactive power (in kVAR) supplied by the capacitor is ____________.

The figure shows the single line diagram of a single machine infinite bus system.

The inertia constant of the synchronous generator $$𝐻 = 5$$ $$MW-s/MVA.$$ Frequency is $$50Hz.$$ Mechanical power is $$1$$ pu. The system is operating at the stable equilibrium point with rotor angle $$\delta $$ equal to $${30^ \circ }$$. A three phase short circuit fault occurs at a certain location on one of the circuits of the double circuit transmission line. During fault, electrical power in pu is $$\,{P_{\max }}\,\,\sin \delta .\,\,\,$$. If the values of $$\delta $$ and $$d$$$$\delta $$$$/dt$$ at the instant of fault clearing are $${45^ \circ }$$ and $$3.762$$ radian/s respectively, then $$\,{P_{\max }}$$ (in pu) is _________.

For a fully transposed transmission line

A 183-bus power system has 150PQ buses and 32 PV buses. In the general case, to obtain the load flow solution using Newton-Raphson method in polar coordinates, the minimum number of simultaneous equations to be solved is ___________.

A function f(t) is shown in the figure. The Fourier transform F($$\mathrm\omega$$) of f(t) is

A signal is represented by $$$x\left(t\right)=\left\{\begin{array}{l}1\;\;\;\left|t\right|\;<\;1\\0\;\;\;\left|t\right|\;>\;1\end{array}\right.$$$ The Fourier transform of the convolved signal y(t)=x(2t) * x(t/2) is

A differentiable non constant even function x(t) has a derivative y(t), and their respective Fourier Transforms are X($$\omega$$) and Y($$\omega$$). Which of the following statements is TRUE?

For the signal f(t) = 3 sin8$$\mathrm\pi$$t + 6sin12$$\mathrm\pi$$t + sin14$$\mathrm\pi$$t, the minimum sampling frequency (in Hz) satisfying the Nyquist criterion is _________.

A sinusoid x(t) of unknown frequency is sampled by an impulse train of period 20 ms. The resulting sample train is next applied to an ideal lowpass filter with a cutoff at 25 Hz. The filter output is seen to be a sinusoid of frequency 20 Hz. This means that x(t) has a frequency of

A continuous-time LTI system with system function H($$\omega$$) has the following pole-zero plot. For this system, which of the alternatives is TRUE?