Which one of the following helps experimental confirmation of the Crystalline state of matter?

The electrical conductivity of pure semiconductor is:

Consider the following statements pertaining to the resistance of a conductor:
1. Resistance can be simply defined as the ratio of voltage across the conductor to the current through the conductor. This is, in fact, Georg Ohm’s law.
2. Resistance is a function of voltage and current.
3. Resistance is a function of conductor geometry and its conductivity
Which of the above statements are correct?

The ratio of ionic radii of Cations i.e.and that of Anions i.e.for stable and unstable ceramic crystal structure, is:

Which one of the following statements is correct?

In an extrinsic semiconductor the conductivity significantly depends upon:

In some substances when an electric field is applied the substance become polarized. The electrons and nucleii assume new geometrical positions and the mechanical dimensions are altered. This phenomenon is called:

In ferromagnetic materials, the net magnetic moment created due to magnetization by an applied field as:

At what temperatures domains lose their ferromagnetic properties?

Which of the following materials does not have paramagnetic properties?
1. Rare earth elements (with incomplete shell)
2. Transition elements
3. Magnesium oxide
Select the correct answer from the codes given below:

In a superconducting magnet, wires of superconducting material are embedded in the thick copper matrix, because while the material is in the superconducting state:

The crystal structure of some Ceramic materials may be thought of being composed of electrically charged Cations and Anions, instead of Atoms, and as such:

Manganin alloy used for making resistors for laboratory instruments contains:

A rolled-paper capacitor of value 0.02  is to be constructed using two strips of aluminiumof width 6 cm, and wax impregnated paper of thickness 0.06 mm whose relative permittivity is 3. The length of foil strips should be:

In a semiconductor diode, cut-in voltage is the voltage:

The transistor is operating in:

The leakage current in an NPN transistor is due to the flow of:

In Early effect:

Maximum energy of electrons liberated photo electrically is:

The response of a Gaussian random process applied to a stable linear system is:
1. A Gaussian random process
2. Not a Gaussian random process
3. Completely specified by its mean and auto covariance functions
Which of the above statements is/are correct?

Consider a system, which computes the ‘MEDIAN’ of signal value in a window of size ‘N’. Such a discrete time system is:

Consider an ideal low pass filter. Such a discrete-time system is:

In a discrete-time complex exponential sequence of frequency  the _o = 1 sequence is:
Which of the above statements is/are correct?
1. Periodic with period
2. Non-Periodic
3. Periodic for some value of period N

The varactor diode has a voltage-dependent:
1. Resistance
2. Capacitance
3. Inductance
Which of the above is/are correct?

The impulse response for the discrete-time system:
Y[n]=0.24 (x[n] + x[n-1] + x[n-2] + x[n-3]) is given by

The product of emitter efficiency (Y) and Base transport factor ( ß⁺) for a BJT is equal to:

Consider a two-sided discrete-time signal(neither left sided, nor right sided). The region of convergence (ROC) of the Z transform of the sequence is:
(a) All region of z-plane outside a unit circle (in z-plane)
(b) All region of z-plane inside a unit circle (in z-plane)
(c) Ring in z-plane
Which of the above is/are correct?

When is a function f(n) said to be left sided?  (n₀ →Positive or negative integer)

Z-transform deals with discrete time systems for their:
1. Transient behaviour
2. Steady-state behaviour
Which of the above behaviours is/are correct?

The response of a linear, time-invariant discrete-time system to a unit step input u[n] is [n]. The system response to a ramp input n u[n] would be:

Which of the following regions of operation are mainly responsible for heating of the transistor under switching operation?
1. Saturation region
2. Cut-off region
3. Transition from saturation to cut-off
4. Transition from cut-off to saturation
Select the correct answer using the codes given below

In a sinusoidal oscillator, sustained oscillations will be produced only if the loop gain (at the oscillation frequency) is

The Class-B push-pull amplifier is an efficient two –transistor circuit, in which the two transistors operate in the following way:

PAC stands for______.

For normal operation of a transistor

Consider the following statements regarding linear power supply:
1. It requires low frequency transformer.
2. It requires high frequency transformer.
3. The transistor works in active region.
Which of the above statements is/are correct?

A full wave rectifier connected to the output terminals of the mains transformer produces an RMS voltage of 18 V across the secondary. The no-load voltage across the secondary of the transformer is

MICR stands for______.

In an Op-Amp, if the feedback voltage is reduced by connecting a voltage divider at the output, which of the following will happen?
1. Input impedance increases
2. Output impedance increases
3. Overall gain increases
Which of the above statements is/are correct?

The transient response rise time (unity gain) of an Op-Amp is 0.05s.The small signal bandwidth is

A negative feedback of   is applied to an amplifier of open-loop gain 1000. What is the change in overall gain of the feedback amplifier, if the gain of the internal amplifier is reduced by 20%?

If the quality factor of a single-stage single tuned amplifier is doubled, the bandwidth will

Consider the following statements related to oscillator circuits:
1. The tank circuit of a Hartley oscillator is make up of a tapped capacitor and a common inductor.
2. The tank circuit of a Colpitts oscillator is make up of a tapped capacitor and a common oscillator.
3. The Wien Bridge oscillator is essentially a two-stage amplifier with an RC bridge in the first stage, and, the second stage serving as inverter.
4. Crystal oscillators are fixed frequency oscillators with a high Q-factor.
Which of the above statements are correct?

The most commonly used transistor configuration for use as a switching devices is

The simplified form of the Boolean expression AB + A (B + C) + B(B + C) is given by

What is the maximum frequency for a sine wave output voltage of 10 V peak with an Op-Amp whose slew rate is 1V/ ?

Which one of the following statements is correct?

The slew rate is the rate of change of output voltage of an operational amplifier when a particular input is applied. What is that input?

Except at high frequencies of switching, nearly all the power dissipated in the switch mode operation of a BJT occurs, when the transistor is in the

Consider the following statements with respect to combinational circuit:
1. The output at any time depends only on the present combination of inputs.
2. It does not employ storage elements.
3. It     performs an operation that can be specified logically by a set of Boolean functions.
Which of the above statements are correct?

Consider the following statements:
a multiplexer
1. selects one of the several inputs and transmit it to a single output.
2. routes the data from a single input to one of many outputs
3. converts parallel data into a serial data
4. is a combinational circuit.
Which of the above statements are correct?

What are the two types of basic adder circuits?

Consider the following statements:
1. An 8-input MUX can be used to implement any 4 variable functions.
2. A 3-line to 8-line DEMUX can be used to implement any 4 variable functions.
3. A 64-input MUX can be built using nine 8-input MUXs.
4. A 6-line to 64-line DEMUX can be built using nine 3-line to 8-line DEMUXs.
Which of the above statements are correct?

The main disadvantage of DTL logic circuits is

Which one of the following statements best describes the operation of a negative-edge triggered D flip-flop?

A 3-bit ripple counter is constructed using three T flip-flops to do the binary counting. The three flip-flops have T-inputs fixed at

The initial content of a four-bit shift register is 1000. What is the register content after it is shifted four times to the right, with the serial input being 111100?

When a large number of analog signal is to be converted to digital form, an analog multiplexer is used. The A-to-D converter most suitable in this case will be

For Emitter-coupled logic (ECL), the switching speed is very high because

A flip-flop is a

Consider the following statements:
The output of a linear circuit, driven with a sine wave at a frequency f, is itself a sine wave
1. at the same frequency
2. with chance of changed amplitude
3. with chances of changed amplitude and phase
Which of the above statements is/are correct? 

Consider the following statements:
The main contribution to photo conduction is by
1. the generation of electron and hole pair by a photon
2. a donor electron jumping into the conduction band because of a photon’s energy
3. a valence electron jumping into an acceptor state because of a photon’s energy Which of the above statements is/are correct? 

Thermal runaway is not possible in FET because as the temperature of the FET increase

For the same network, with 6 V DC connected at port A, 1 Ω connected at port B draws 7/3 A. if 8 V DC is connected to port A, the open circuit voltage at port B is

A signal may have frequency components which lie in the range of 0.001 Hz to 10 Hz. Which one of the following types of couplings should be chosen in a multistage amplifier designed to amplify the signal? 

If an input impedance of op-amp is finite, then which one of the following statements related to virtual ground is correct ? 

Hysteresis is desirable in a Schmitt-trigger because 

In a photoconductive cell the resistance, of the semiconductor material varies with intensity of incident light. 

In graded index multimode optical fiber the refractive index of the core is

Consider the following factors:
1. Number of turns of the coil
2. Length of the coil
3. Area of cross-section of the coil
4. Permeability of the core
On which of the above factors does inductance, depend?

Consider the following statements:
1. Fleming’s rule is used where induced e.m.f. is due to flux cutting.
2. Lenz’s law is used when the induced e.m.f. is due to change in flux linkages.
3. Lenz’s law is direct consequence of the law of conservation of energy.
Which of the above statements are correct? 

A conductor of length 1 m moves at right angles to a uniform magnetic field of flux density 2Wb/m² with a velocity of 50 m/s. What is the value of the induced e.m.f. when the conductor moves at an angle of 30° to the direction of the field ?

The slip of a 400 V, 3-phase, 4-pole, 50 Hz machine running at 1440 r.p.m. is

A 500 HP, 440 V, 3-phase, 50 Hz induction motor runs at 950 r.p.m. when on full load with a synchronous speed of 1000 r.p.m. for this condition, the frequency of the rotor current will be 

By adding resistance in the rotor circuit of a slip ring induction motor, the starting current

Consider the following statements with regards to an induction motor:
1. Maximum torque is independent of rotor resistance.
2. Starting torque is maximum when rotor resistance equals rotor reactance.
3. Torque is very sensitive to any changes in supply voltage.
Which of the above statements are correct? 

A transformer has 2% resistance and 5% reactance. What is its voltage regulation at full load with 0.8 p.f. lagging? 

A voltage is generated across a piezoelectric material, 0.5 cm thick, subjected to an impact of 5 N/m². The voltage coefficient of the material is 23 kV-m/N. The magnitude of the voltage generated will be

The ‘residual resistivity’ of a metal is

Electrical conductivity, thermal conductivity and magnetic properties of ceramic material are

At temperature of 298 Kelvin, Silicon is not suitable for most-electronic applications, due to small amount of conductivity. This can be altered by

By doping Germanium with Gallium, the types of semi-conductors formed are
1. N type
2. P type
3. Intrinsic
4. Extrinsic

An n-type of silicon can be formed by adding impurity of:
1. Phosphorous
2. Arsenic
3. Boron
4. Aluminum 
Which of the above are correct ?

According to Einstein’s relationship for a semiconductor, the ratio of diffusion constant to the mobility of the charge carriers is

Swept-out voltage in PIN diode happens when PIN diode is

The number of holes in an N-type silicon with intrinsic value 1.5 × 10¹⁰/cm³ and doping concentration of 10¹⁷/cm³, by using mass-action law is

A tunnel-diode is best suited for

Small recovery time of a diode is most significant for

In JFET, when operated above the pinch-off voltage, the

Thermal runaway is not possible in FET because, as the temperature of FET increases

Consider the following statements regarding an N-P-N Bipolar Junction Transistor:
1. Emitter diode is forward biased and collector diode is reverse biased
2. Emitter has many free electrons
3. Free electrons are injected into base and pass through collector
4. Depletion layers around junction J1 and J2 of BJT are widened 
    Which of the above statements are correct?

A freewheeling diode T phase controlled rectifier

The zeners incorporated within the encapsulations of some MOSFETs are meant for

When UJT is used for triggering an SCR, the wave-shape of the signal obtained from UJT circuit is

Darlington pairs are frequently used in linear ICs because, they

In a MOS capacitance fabricate on a P-type semiconductor, strong inversion occurs, when potential is

A CMOS amplifier when compared to an N channel MOSFET has the advantage of

Consider the following statements regardingoptocouplers:
1. Optocouplers are LEDs driving photodiodes in a single package to provide electrical isolation between input and output
2. Optocouplers is LED driving a phototransistor in a single package that replaces pulse transformers working at input zero crossing
3. Optocouplers are used as temporary non fixed joints between optical fibre terminations 
  Which of the above statements are correct?

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

The basic structure of an avalanche photodiode is