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

A five digits number is formed using the digits 1, 3, 5, 7 and 9 without repeating any of them. What is the sum of all such possible five digit numbers ?

Examples of an active display and a passive display respectively are

The dc resistivity and permeability exhibited by a type 1 superconductor are respectively

Statement (I):One of the mechanisms by which a transistor’s usefulness may be terminated, as the collector voltage is increased, is called punch through.
Statement (II): Punch through results from the increased width of the collector-junction transition region with increased collector-junction voltage

Statement (I): Conduction takes place in an enhancement MOSFET only for gate voltages below the threshold level.
Statement (II):In an enhancement MOSFET, a channel of semiconductor of the same type as the source and drain is induced in the substrate by a positive voltage applied to the gate.

Statement (I): MOSFET is a field effect transistor whose drain current is controlled by the voltage applied at the gate.
Statement (II): MOSFET is an insulated gate FET

Statement (I): All passive components can be fabricated in a single chip.
Statement (II): As opposed to discrete circuits where all components are separately inserted and connected, in an integrated circuit, they are simultaneously created on a chip of semiconductor material during manufacturing

What is an advantage of MOS transistor structure in integrated circuits?

An LTI system has a wide-sense stationary (WSS) input signal with zero mean. Its output is

In degenerately doped n conduction n-type semiconductor, the Fermi level lies in conduction band when

The purpose of connecting a Zener diode in a UJT circuit, used for triggering thyristors, is to

Statement (I):With a small additional energy, usually thermal, the valence electrons in germanium can become free electrons.
Statement (II):The valence electrons in germanium are in the fourth orbit and are at high energy level.

Statement (I): An FET is a current-controlled device.
Statement (II): Operation of an FET depends only on majority.

Statement (I): Thermal runaway is not possible in an FET.
Statement (II): As the temperature of an FET increases, the mobility of carriers decreases.

Statement (I): In an enhancement type MOSFET (with n-type source and drain regions), only positive voltage can be applied to the gate with respect to the substrate (p-type).
Statement (II): Only with a positive voltage to the gate, an ‘inversion layer’ is formed and conduction can take place

For a fully transposed transmission line         

The best device for improving the switching speeds of bipolar transistors is

The early effect in bipolar junction transistor is caused by

To get higher cut-off frequency in a BJT, base sheet resistance should be

A BJT operates as a switch

What is the biasing condition of junctions in bipolar junction transistor to work as an amplifier?

In a JFET, operating above pinch-off voltage, the

If V_cc = 18V, voltage divider resistances R₁ = 4.7 kΩ and R₂ = 1500 Ω, what is the base bias voltage?

An SCR has an anode supply of sine voltage 200V_r.m.s., 50 Hz applied through a 100 Ω resistor and fired at an angle of 60°. Assuming no voltage drop, the r.m.s. value of the output voltage is nearly

In a GTO, anode current begins to fall when gate current

An SCR is turned off when its turn-off time is

The bandwidth of a digitally recorded signal primarily depends upon

While measuring the voltage developed by a thermocouple, it is found that there is always an offset voltage. This is due to

For an antenna, radiation intensity is defined as

A source of (power/energy) feeds the input port of an amplifier and the output port is connected to a ‘load’. The input impedance of the ideal amplifier should ideally be

Medium doping in Silicon and Germanium corresponds to impurity of the order of

An electric field is applied to a semiconductor. Let the number of charge carriers be n and the average drift speed by v. If the temperature is increased then

Statement (I): Centre tap transformer is essential for a centre-tapped rectifier.
Statement (II): In half wave rectification minimum two diodes are required.

Statement (I): Power factor is a measure of the power flow in the insulator and should be low.
Statement (II): It varies with the temperature and usually increases with the rise in temperature of the insulation.

Statement (I): An SCR has a current controlled negative resistance characteristic.
Statement (II):For a given current the voltage can be determined while for a given voltage current cannot be determined.

Statement (I): JEET is operated in depletion mode only.
Statement (II): The input resistance of a MOSFET is several orders of magnitude greater than that of a JEET.

Statement (I): A photodiode is an example of a photo-conductive sensor.
Statement (II): A photodiode can be used as either a photo conductive or a photo resistive sensor.

A heavily doped semiconductor has

A Zener diode has the following properties:
1. It is properly doped crystal diode with sharp breakdown.
2. It is reverse biased
3. Its forward characteristics are just that of ordinary diode
4. Its reverse characteristics are like and ordinary diode

A tunnel diode is a p-n junction in which