When a very small amount of higher conducting metal is added to a conductor, its conductivity will 

An electrically balanced atom has 30 protons in its nucleus and 2 electrons in its outermost shell. The materials made of such atom is

The temperature coefficient of resistance of a doped semiconductor is

In the slice processing of an integrated circuit

Permanent magnet loses the magnetic behaviour when heated because of
1. atomic vibration
2. dipole vibration
3. realignment of dipoles
Which of the above are correct?

A Zener regulator has an input voltage varying between 20 V and 30 V. The desired regulated voltage is 12 V, while the load varies between 140  and 10k  The maximum resistance in series with the unregulated source and Zener diode would be

A short in any type of circuit (series, parallel or combination) causes the total circuit
1. resistance to decrease
2. power to decreases
3. current to increase
Which of the above are correct?

An air-cored solenoid of 250 turns has a cross-sectional area A = 80 cm² and length l = 100 cm. The value of its inductance is

The current in a coil changes uniformly from 10 A to 1 A in half a second. A voltmeter connected across the coil gives a reading of 36 V. The self-inductance of the coil is

In a mutually coupled circuit, the primary current is reduced from 4A to zero in 10 s.  A voltage of 40000 V is observed across the secondary. The mutual inductance between the coils is

A CRO screen has 10 divisions on the horizontal scale. If a voltage signal 5 sin (314t + 45°) is examined with a line base setting of 5 ms/div, the number of signals displayed on the screen will be 

Which one of the following conditions will be correct when three identical bulbs forming a star are connected to a three-phase balanced supply?
 

Loading by the measuring instruments introduces an error in the measured parameter. Which of the following devices gives most accurate result?

A moving-coil galvanometer can be used as a DC ammeter by connecting

Consider the following types of damping:
1. Air-friction damping
2.Fluid-friction damping
3.Eddy-current damping
PMMC type instruments use which of the above?

In data acquisition system, analog data acquisition system is used

During the measurement of resistance by Carey Foster bridge, no error is introduced due to
1.contact resistance
2. Connecting leads
3.thermoelectric e.m.f.
which of the above are correct?

Which of the following is true for the complete response of any network voltage or current variables for a step excitation to a first-order circuit?

A piezoelectric crystal has a coupling coefficient K of 0.32. How much electrical energy must be applied to produce output energy of 7.06 × 10^–3 J?

A wattmeter reads 10 kW, when its current coil is connected in R phase and the potential coil is connected across R and neutral of a balanced 400 V (RYB sequence) supply. The line current is 54 A. If the potential coil reconnected across B-Y phases with the current coil in R phase, the new reading of the wattmeter will be nearly

For a type-I system, the intersection of the initial slope of the Bode plot with 0dB axis gives

The desirable features of a servomotor are

Permeance is inversely related to

Consider the following statements regarding an ideal core material:
1. It has very high permeability.
2. It loses all its magnetism when there is no current flow.
3. It does not saturate easily.
Which of the above statements are correct?

The characteristic impedance of a transmission line depends upon

A semiconductor differs from a conductor in that it has

Which of the following circuits is used for converting a sine wave into a square wave?

Which of the following elements of electrical engineering cannot be analyzed using Ohm’s law ?

Consider the following statements: A power supply uses bridge rectifier with a capacitor input filter. If one of the diodes is defective, then
1. The dc load voltage will be lower than its expected value
2. Ripple frequency will be lower than its expected value
3. The surge current will increase considerably
Which of the above statements are correct?

Three identical amplifiers each having a voltage gain of 50 are cascaded. The open loop voltage gain of the combined amplifier is

A clamper circuit
1. Adds or subtracts a dc voltage to or from a waveform
2. Does not change the shape of the waveform
Which of the above statements are correct? 

If a carrier of 100% modulated AM is suppressed before transmission, the power saving is nearly

When the modulating frequency is doubled the modulation index is halved and the modulating voltage remains constant. This happens when the modulating system is

The four basic elements in a PLL are loop filter, loop amplifier, VCO and

In a frequency modulated (FM) system, when the audio frequency is 500 Hz and audio frequency voltage is 2.4 V, the frequency deviation is 4.8 kHz. If the audio frequency voltage is now increased to 7.2 V then what is the new value of deviation?

In an IGBT cell the collector and emitter are respectively

The main units in a pulse code modulator are:
1. Sampler
2. Quantiser
3. Encoder
4. Comparator

NAND and NOR gates are called ‘Universal’ gates primarily because

To turn-off a GTO what is required at the gate?

In a power transformer, the core loss is 50 W at 40 Hz and 100 W at 60 Hz, under the condition of same maximum flux density in both cases. The core loss at 50 Hz will be

Consider the following advantages of a distributed winding in a rotating machine:
1. Better utilization of core as a number of evenly placed small slots are used
2. Improved waveform as harmonic emf’s are reduced
3. Diminished armature reaction and efficient cooling
Which of the above advantages are correct?

The breadth factor for 3rd harmonic emf of a 3-phase, 4-pole, synchronous machine having 36 stator slots is

Consider the following factors for a dc machine:
1. Interpole
2. Armature resistance
3. Reduction in field current
Which of the above factors are responsible for decrease in terminal voltage of a shunt generator?

A dc motor develops an electromagnetic torque of 150 N-m in a certain operating condition. From this operating condition, a 10% reduction in field flux and 50% increase in armature current is made. What will be new value of electromagnetic torque? 

If the capacitor of a capacitor-start single-phase motor fails to open when the motor picks up speed, 

For a 3-phase induction motor, what fraction/ multiple of supply voltage is required for a direct-on-line starting method such that starting current is limited to 5 times the full-load current and motor develops 1-5 times full-load torque at starting time?

What is the material of slip-rings in an induction machine?

The stator loss of a 3-phase induction motor is 2 kW. If the motor is running with a slip of 4% and power input of 90 kW, then what is the rotor mechanical power developed?

In a single-phase capacitor-start induction motor, the direction of rotation

A transformer may have negative voltage regulation if the load power factor (p.f.) is

If a square matrix of order 100 has exactly 15 distinct eigenvalues, then the degree of the minimum polynomial is 

For high speed reading and storing of information in a computer, the core shall be of 

Soft magnetic materials should have 

Orbital magnetic moment of an electron, in an atom, is of the order of 

When the temperature of a ferromagnetic material exceeds the Curie temperature, it behaves similar to a 

What is the correct sequence of the following materials in ascending order of their resistivity ?
1. Iron
2. Silver
3. Constantan
4. Mica
5. Aluminium
Select the correct answer using the codes given below : 

In the first Cauer network, with a pole at infinity, the first element must be

The total magnetic moment
1. is called saturation magnetization.
2. depends on the number of magnetic dipoles per unit volume, the instant electric current and the area of the current loop.
Which of the above statements is/are correct ? 

Susceptibility of a diamagnetic material is 1. Negative
2. Positive
3. Dependent on the temperature
4. Independent of the temperature 

Superconductivity is a material property associated with 

An atom in a crystal vibrates at a frequency, determined by
1. Crystal heat current
2. Crystal temperature
3. The stiffness of the bonds with neighbour atoms
Select the correct answer using the codes given below: 

Consider the following statements:
1. Nano means 10^–9 so that nano materials have an order of dimension higher than the size of atom and come in the form of rods, tubes, spheres or even thin sheets/films
2. Nano materials have enhanced of changed structural property
3. Nano elements lend themselves to mechanical processing like rolling, twisting, positioning
4. Nano elements show important electrical, magnetic and optical characteristics that are useful in electrical industry
Which of the above statements are correct? 

For a two-part reciprocal network, the three transmission parameters are A = 4, B = 7 and C = 5. What is the value of D? 

Consider the following as representations of reciprocity in terms of z-parameters:
1. z₁₁ = z₁₂                     2. z₁₂ = z₂₂
3. z₁₂ = z₂₁
Which of the above representations is/are correct? 

Kirchhoff’s current law is applicable to
1. Closed loops in a circuit
2. Junction in a circuit
3. Magnetic circuits
Which of the above is/are correct? 

Which of the following are satisfied in a non-linear network?
1. Associative               2. Superposition
3. Homogeneity             4. Bilaterality
Select the correct answer using the codes given below: 

Consider the following statements:
1. Network theorems are not derivable from Kirchhoff’s law
2. To get the Norton current, one has to short the current source
3. Thevenin’s theorem is suitable for a circuit involving voltage sources and series connections
Which of the above statements is/are correct? 

What is the octal equivalent of (5621.125)10? 

What is the hexadecimal representation of (657)₈? 

In potential transformers, the secondary turns are increased slightly and the primary and secondary windings are wound as closely as possible to compensate for 

Which one of the following methods is used for the measurement of high resistances? 

Consider the following statements with regard to induction type wattmeter:
1. Can be used on both ac and dc systems.
2. Power consumption is relatively low.
3. It is accurate only at stated frequency and temperature.
Which of the above statements is/are correct? 

A computer system has a cache with a cache access time T_C = 10 ns, a hit ratio of 80% and an average memory access time T_M = 20 ns. What is the access time for physical memory T_P? 

The minimum number of arithmetic operations required to evaluate the polynomial P(X) = X⁵+ 8X³+ X for a given value of X using only one temporary variable is 

A freewheeling diode in phase-controlled rectifiers

Assuming both the voltage sources are in phase, the value of R for which maximum power is transferred from circuit A to circuit B is

For the intrinsic gallium-arsenide, the conductivity at room temperature 25°C is 10^-6 (ohm-m)^-1, the electron and hole nobilities are 0.85 m²/V-s and 0.04 m²/V-s respectively. What is the intrinsic carrier concentration at the room temperature?

The resistivity of intrinsic germanium at 30°C is 0.46 –m. What is the intrinsic carrier density at 30°C if the electron mobility is 0.38 m²/V-s and the hole mobility is 0.18 m²/V-s?

Heat conduction in a semiconductor takes place

Brewster angle is the angle when a wave is incident on the surface of a perfect dielectric at which there is no reflected wave and the incident wave is

An electrical breakdown of a p-n junction occurs if

The chief deterrent to the widespread application of superconducting materials is

Which one of the following properties is not observed in the carbon nanotubes ?

The evidence for the importance of electron-phonon interaction in super-conductors comes from

Which one of the following materials is used for cable insulation ?

For high speed reading and storing of information in a computer, the material used is

The temperature above which an anti-ferromagnetic material becomes paramagnetic is called

Which effect is the converse of Peltier effect ?

Magnetic materials which may be readily magnetized in either direction are

Consider the following statements regarding a ferromagnetic material:
1.Below the ferromagnetic Curie temperature, the ferromagnetic materials exhibit hysteresis effect.
2.The coercive force is the filed required to reduce the flux density to zero. 
Which of the above statements is/are correct?

The impact ionization phenomenon in semiconductor may be viewed as the reverse process of

Refractive index of a slice glass can be reduced by doping it with tiny amount of

If a diameter of a copper wire is increased by two times keeping its terminal voltage same, then the drift velocity will

In an induction type energy meter, the steady speed attained by the rotating disc is
1.Proportional to the deflecting torque.
2.Proportional to the resistance of the path of eddy currents.
3.Inversely proportional to the effective readings of disc from its axis.
4.Inversely proportional to the square of brake magnetic flux. 
Which of the above are correct?

If ‘KCLFTSB’ stands for ‘best of  luck’ and ‘SHSWDG’ stands for ‘good wishes’, which of the following indicates ‘ace the exam’?

Consider  the following statements associated with the basic electrostatic properties of ideal conductors:
1.The resultant field inside is zero.
2.The net charge density in the interior is zero.
3.Any net charges reside on the surface.
4.The surface is always equipotential.
5.The field just outside is zero. 
Which of the above statements are correct?

A semiconductor device made out of a material having very high temperature coefficient of resistance is

The electrical conductivity of a semiconductor increases with increase in temperature because

Which of the following are associated with soft superconductors?
1.Silsbee’s rule
2.Meissner effect
3.Faraday rotation
4.Curie-Weiss law

In a two-channel oscilloscope operating in x-y mode, two in-phase 50 Hz sinusoidal waveforms of equal amplitude are fed to the two channels. What will be the resultant pattern on the screen?