Find by applying Euler's method to ·the initial value problem

dy/dx y(0)=1.Take step size h=0.25


Four· charges q1 -2·0 x Coulomb, q2 =3·0 x Coulomb, q3 2.0 x Coulomb and q4 1·0 x Coulomb are placed at four corners of a square of 2·0 metre side. Find out the potential at the centre of the square.


Discuss the biasing conditions of p-n junctions in a Bipolar· Junction transistor under saturation and cut off conditions.

Determine whether the transistor circuit shown can be termed as being saturated.
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Draw the variation of space charge, electric field and electrostatic potential across a semiconductor p-n junction.

Two parallel plates are· separated 0·25 cm apart. The gap is partially filled with 0·23 cm thick sheet of fibre with 5. A potential difference of 2·5 Kv· is. applied across · the plate. Determine the electric field strength in the fibre and air film between the fibre and the plate. Will the air break down Dielectric strength of air can be taken as 30 KV /cm.



What is meant by the term pinch off voltage of a JFET? Draw the drain characteristics of a JFET for VGS= 0V show the pinch off voltage in the diagram.
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Define the terms transconductance and amplification factor of a JFET.

In an FET, as VGs, the gate-to-source voltage is varied from -1·5 V to keeping VDs constant, ID of an FET decreases from 7·5 mA to 5·5 mA. What is the transconductance of the FET If the a.c. drain resistance is 21O kilo ohms, find the amplification factor.
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Find the absolute maximum and minimum values of the function
f x^2 3y^2 y over the region x^2 2y^2 1
·



Find the current flowing through the 6 ohms resistor in the circuit shown using Thevenin's theorem. Find also the power delivered to it.

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For the common emitter amplifier shown, find the values of the collector current Ic and VCE if ßdc 150.

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Draw the a.c. equivalent circuit of the base the transistor amplifier, Find the value of the input resistance and the voltage gain. Discuss the effect of
the capacitor C3 on the voltage gain when V¡ 10 mV. (Please refer to amplifier circuit above)



Find the volume enclosed between the surfaces
x^2 z^2 16 and x^2 -4x



A circuit is shown.
Deter mine the 'value of the reactance X which makes the source current in phase with the source voltage.
Compute also the effective value of the current for the condition described in part

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Find the minimum voltage gain and input resistance of the amplifier gm.; 2100µ Siemens) for the circuit of the JFET amplifier as shown in figure

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Find the value of the lower cut off frequency for the MOSFET amplifier depicted in figure. Assume C1= 0.00l µF, RG=10 Mn, RD 4.7K,
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Find the eigenvalues and eigenvectors of the matrix is

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A balanced three-phase, 208 volts generator supplies a total of 18,00 Watts at a line current of 10. Amp. When three identical impedances are arranged in Y-connection across the line terminals of. the generator calculate the resistive and reactive components of each phase impedance. Sketch also the phase and magnitude relations between phase and line voltages of a connected three phase system


State the effects of negative feedback in an amplifier,

Draw the circuit diagram of a series ·voltage negative feedback and derive an expression for its input impedance.

Find the input impedance of a series voltage negative feedback if the gain of the amplifier without feedback is 100,000 and the feedback ratio is 0·02.

Draw the electrical equivalent circuit diagram of a crystal oscillator. Derive expression for the resonant frequencies of the oscillator and. show the variation of reactance of the crystal with frequency.



What are ferrites How they are derived Enumerate magnetic, electrical and mechanical properties of ferrites (two each).

Differentiate between the following:
Transducers and Inverse Transducers

Analog and Digital Transducers

Active and Passive Transducers
.

Perform the following binary subtraction and give the result in decimal value also
11001 1100

Simplify the Boolean function F xy


Give the output of the following program:
int main

char str "IndiaBIX";
printf s
",
return ·



When 100 Volts is applied across a pure resistance, it draws a current of 5 amperes. The uncertainties in measurements of voltage and current are ± 0·2 volts and ± 0·06 ampere respectively. Calculate the power dissipated in resistance and uncertainty in Power in when Power P is calculated as VI.

Calculate the number of vacancies per cubic meter in iron at 850ºC with the following data
.
Energy vacancy formation 1·08 eV/atom
one mole 6.022 x 10^23
Density at 850ºC 7·65
Atomic weight of iron 55·85 g/mol
Boltzman's constant · 1·38 x 10^-23 J/atom·K


State 3 effects of moisture on insulation and explain any two methods adopted to protect them against moisture along with salient features.
Show that the surface area to volume ratio increases with the reduction in radius of nanoparticle. 'Plot a graph of surface to volume ratio as a function of radius.


For the Bridge circuit shown, obtain the expression for mutual inductance when the bridge is at balance, in terms of circuit parameters.


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Draw the basic organisation of a computer system and indicate the flow of instructions and data.


Explain in brief the functions of each of the units shown in


For a face centered cubic metal state with reasons the number of atoms assigned per unit cell and coordination number. Also deduce a value for atomic packing factor.

Determine the diameter of the lead wire to pass maximum super current of 0·0021 mA at 5·0 K. The critical temperature and critical magnetic field for lead are respectively 7·l8 K and 6·5 x A/m.

The network shown in figure is connected to 3-phase, 400 50 Hz supply with phase sequence abc. Calculate the reading of the wattmeter.

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Bring out the concept of virtual memory and briefly point out its. operation.
What is a page-fault; how is it managed



Name 5 properties that are exhibited by superconductors. Draw the magnetising curve for. Type-I and Type-II superconductors specifying regions of conducting states.

Explain how some ferrite is suitable for use in magnetic memory core in computers. Explanation should be based on the hysteresis loop of the ferrite.


State only the methods to minimise the ratio error of a current transformer. A 1000/5 50 Hz current transformer has a bar primary and has total secondary
burden of 1 ohm (non-inductive Calculate the primary current and phase angle error for a rated current of 5 amperes. The magnetising current is 100 A and excitation loss is negligible. Assume there· is no turns compensation.


What is a computer network? Distinguish between LAN and WAN.

Explain in brief what is network topology by illustrating four major topology schemes.