In the transistor amplifier shown in figure, the ratio of small signal voltage gain when the emitter resistor is bypassed by the capacitor $$'{C_e}'$$ to when it is not bypassed. (Assuming of simplified approximate $$h$$- parameter model for transistor) is

The depletion region (or) space charge region (or) transition region in a semiconductor $$p-n$$ junction diode has

A non inverting op - amp amplifier is shown in figure. The o/p voltage is

Let the magnitude of the gain in the inverting op - amp amplifier circuit shown be $$x$$ with switch $${S_1}$$ open. When the switch $${S_1}$$ is closed, the magnitude of gain becomes.

The closed - loop transfer function of a control system is given by $${{C\left( s \right)} \over {R\left( s \right)}} = {1 \over {\left( {1 + s} \right)}}$$
For the input $$\,r\left( t \right)\,\, = \,\,\sin \,t,$$ the steady state value of $$c(t)$$ is equal to

For the system shown in Figure, with a damping ratio $$\xi $$ of $$0.7$$ and an undamped natural frequency $${\omega _n}$$ of $$4$$ rad/sec, the values of $$' K '$$ and $$' a '$$ are

The unit - impulse response of a unity - feedback control system is given by $$c\left( t \right) = - t{e^{ - t}} + 2\,\,{e^{ - t}},\,\left( {t \ge 0} \right)$$ the open loop transfer function is equal to

Consider the unit step response of a unity feedback control system whose open loop transfer function is $$G\left( s \right) = {1 \over {s\left( {s + 1} \right)}}.$$ The maximum overshoot is equal to

For a feedback control system of type $$2,$$ the steady state error for a ramp input is

The unit impulse response of a system is given as $$c\left( t \right) = - 4{e^{ - t}} + 6{e^{ - 2t}}.\,\,\,$$ The step response of the same system for $$\,t \ge 0$$ is equal to

The Boolean expression for the output of the logic circuit shown in figure is

In a $$8085$$ microprocessor, the following instructions may result in change of accumulator contents and change in status flags. Choose the correct match for each instruction.

In the series $$RC$$ circuit shown in Fig. the voltage across $$C$$ starts increasing when the $$d.c.$$ source is switched on. The rate of increase of voltage across $$C$$ at the instant just after the switch is closed (i.e., at $$t = {0^ + }$$), will be

In the circuit shown in Fig. $$X$$ $$-$$ is an element which always absorbs power. During a particular operation, it sets up a current of $$1$$ $$amp$$ in the direction shown and absorbs a power $${P_{x}}.$$ It is possible that $$X$$ can absorb the same power $${P_x}$$ for another current $$i.$$ Then the value of this current is

A coil (which can be modeled as a series $$RL$$ circuit) has been designed for high $$-$$ $$Q$$ performance at a rated voltage and a specified frequency. If the frequency of operation is doubled, and the coil is operated at the same rated voltage, then the $$Q$$$$-$$factor and the active power $$P$$ consumed by the coil will be affected as follows

The v - i characteristic as seen from the terminal pair (A,B) of the network of Fig.(1) is shown in Fig.(2). If an inductance of value 6 mH is connected across the terminal - pair (A,B), the time constant of the system will be

An advantage of a permanent magnet moving coil instrument is that it is

The scale of a voltmeter is uniform. Its type is

For a given frequency, the deflecting torque of an induction ammeter is directly proportional to

A water boiler at home is switched on to the $$A.C$$ mains supplying power at $$230$$ $$V/50$$ $$Hz.$$ The frequency of instantaneous power consumed by the boiler is

The moving coil in a dynamometer wattmeter is connected

In an oscilloscope the input to the horizontal plates is a $$100Hz$$ voltage signal. The lissajous patterns $$(A), (B)$$ and $$(C)$$ will be generated when different frequency voltage signals are applied to vertical plates. Match each lissajous pattern to the corresponding frequency by

In Figure. The characteristic that corresponds to the variation of synchronous reactance of synchronous motor with field current is

Unbalanced supply voltage given to a $$3-$$ phase, data-connected induction motor will cause

When the supply voltage to an induction motor is reduced by $$10\% $$, the maximum torque will decrease by approximately

In case of a split phase motor, the phase shift between currents in the two windings is around

An induction motor having full load torque of $$60$$ $$Nm$$ when delta-connected develops a starting torque of $$120$$ $$N$$-$$m.$$ For the same simply voltage, if the motor is changed to star-connection, the starting torque developed will be

In an induction motor, if the air gap is increased

During hunting of synchronous motor

The per unit voltage of two synchronous machines connected through a lossless line are $$0.95\,\,\angle \,{10^0}\,\,$$ and $$1.0\,\,\angle \,{0^0}\,\,$$. Match the two sides in the following
$$(a)$$ Real power of Machine $$1$$
$$(b)$$ Reactive power of machine $$1$$
$$(c)$$ Power factor of Machine $$1$$

$$(P)$$ Positive real power
$$(Q)$$ Positive reactive power
$$(R)$$ Negative real power
$$(S)$$ Negative reactive power
$$(T)$$ Leading power factor
$$(U)$$ Lagging power factor

A $$4$$ pole dynamo with wave wound armature has $$51$$ slots containing $$20$$ conductors in each slot. The induced $$emf$$ is $$357$$ volts and the speed is $$5800$$ $$rpm$$. The flux per pole will be

The function of oil in a transformer is

Auto-transformer is used in transmission and distribution

Keeping in view the requirement of parallel operation, which of the $$3$$-phase connections given below are possible?

The torque speed characteristic of a Repulsion motor resembles which of the following dc motor characteristic?

Which type of motor is most suitable for computer printer device?

The energy stored in the magnetic field of solenoid $$30$$ $$cm$$ long and $$3$$ $$cm$$ diameter wound with $$1000$$ turns of wire carrying a current of $$10$$ $$A$$ is

If v, w, q stand for voltage, energy and charge, then v can be expressed

Which semiconductor power device out of the following is not a current triggered device?

The Triac can be used only in

Which of the following does not cause permanent damage of an $$SCR?$$

In a $$3$$ - phase controlled bridge rectifier, with an increase of overlap angle the output $$dc$$ voltage

In a thyristor $$dc$$ chopper which type of commutation results in best performance?

For a $$500$$ Hz frequency excitation, a $$50$$ km short power line will be modeled as

For equilateral spacing of conductors of an untransposed $$3$$-phase line, we have

During a disturbance on synchronous machine, the rotor swings from A to B before finally settling down to a steady state at a point C on the power angle curve. The speed of the machine during oscillation is synchronous at point(s)

For an unbalanced fault, with paths for zero sequence currents, at the point of fault

Resistance switching is normally employed in

If the fault current is $$2000$$ A, the relay setting is $$50$$% and CT ratio is $$400:5,$$ the plug setting multiplier will be

The per unit voltages of two synchronous machines connected through a lossless line are $$0.95\,\angle {10^ \circ }$$ and $$1.0\,\angle {0^ \circ }.$$ Match the two sides in the following

Which material is used in controlling chain reaction in a nuclear reactor?

If the reference bus is changed in two load flow runs with same system data and power obtained for reference bus taken as specified P and Q in the latter run

A periodic rectangular signal, $$x(t)$$ has the waveform shown in Figure. Frequency of the fifth harmonic of its spectrum is