Find the area of the region bounded by the curves $$y = x^{2}, y = \frac{1}{x}$$ and $$x = \frac{1}{2}$$ (see in graphical representive figure)
ISRO Scientist or Engineer Electronics Dec 2017
For the following questions answer them individually
Find the Eigen values $$\lambda$$ in the system $$\begin{bmatrix}4 & 1 \\3 & 2 \end{bmatrix}$$ $$\begin{bmatrix} x \\ y \end{bmatrix}$$ =\lambda $$\begin{bmatrix} x \\ y \end{bmatrix}$$
Find the transient response of a pair of complex poles as given below
A random variable z , has a probability density function f(z) where $$f(Z) =e^{-z} O\leq Z < \infty$$ the probability of $$O \leq Z \leq 2$$ will be approximately
Evaluate $$\lim_{x \rightarrow 2} \frac{\sqrt{x^{2}+5-3}}{x^{2}-2x}$$
What is the R.M.S of following waveform if the average value is zero?
A radar system uses TWTA as high power RF source for transmitting 300W Peak Power. The efficiency of transmitter during pulse is 75% and the transmit duty is 25%. If the DC
power required during pulse off period is 20W. The average power dissipation in TWTA is
The ramp signal $$(V_{t} : 0 to 5V)$$ is compared with the Soft-Start Signal provided by N-channel MOSFET $$(Q_{1} )$$ for Amplifier $$( A_{1} )$$ output. If $$Q_{1}$$ having low threshold voltage of 0.7V and 1 negligible ON resistance. What is the duty of $$c_{1}$$ output signal of comparator $$(C _{1})$$ after $$100 \mu$$ Sec?
A High speed digital Subsystem requires three voltages $$V_{1} , V_{2}$$ and $$V_{3}$$ with 1 : 2 : 1 power 3 ratings respectively. The power supply is designed with the distribute power conversion scheme as shown in the following figure. What is the overall power conversion efficiency?
If the transformer and diodes in the following circuit are ideal, Find out the value of Capacitor (Co) provides 5% ripple voltage across $$R_{L}$$.
(Assume that $$\sin^{-1} (0.95) \sim \frac{2 \pi}{5}$$ in Radians $$\ln(0.95) = -0.051$$)
Relationship between doppler frequency shifts of two radars A and B having 0.1 foot and 0.05 foot wavelengths, approaching the target at 1000 feet per second and 2000 feet per
second rate respectively, will be
A sinusoidal input which can be reproduced in an OP-AMP without any distortion having slew rate of $$10 \pi \frac{V}{\mu s}$$ and 5V peak output amplitude, has the maximum frequency of
Which of the following is NOT a characteristic of Schottky Diode?
A Sensistor exhibits the following characteristics
When an electromagnetic wave is incident on an object having surface roughness comparable to the wavelength, then
For the following circuit, determine the output voltage $$‘V_{0}’$$ in terms of input voltages $$V_{1}$$ and $$V_{2}$$ , assuming $$A_{1} and A_{2}$$ are ideal op-amps
Dominant mechanism for motion of charge carriers in forward and reverse biased silicon p-n junctions are
Which of the following is NOT true about opto-couplers?
Which of the noise types is dominant in Metal Semiconductor Field Effect Transistor (MESFET) when compared to Bipolar Junction Transistor (BJT)?
Which factor determines the range resolution of a radar?
A signal having frequency component from DC-2KHz is to be Pulse code Modulated with a 6 bit Encoder. Minimum carrier bandwidth required is?
Which of the following is NOT true for Schmitt Trigger?
For the silicon transistor shown in the figure below, the value of $$I_{B}$$ is?
Which one of the following statement is not true for static random access memory (SRAM)
Which of the following statement is not true
The Eddy current loss is proportional to the
The temperature below which certain materials are antiferromagnetic and above which they are paramagnetic is called
In metals, the thermal conductivity K and electrical conductivity $$\sigma$$ are related as $$ \frac{K}{\sigma T} = L$$ is Known as the flux density is increased from 0 to 2.5 T,$$\mu_{r}$$ will
In a specimen of ferromagnetic material with saturation magnetization as 8000 Gauss, as the flux density is increased from 0 to 2.5 T, $$\mu_{r}$$ will
The cavity magnetron uses strapping to
The TWT is sometimes preferred to the magnetron as a radar transmitter output tube because it is
One of the reason why conventional vacuum valve tubes not used at microwave frequencies is that their
In a telecommunication trans-receive system, the transmitting antenna with antenna aperture of 1m is fed with 1W of power at 10GHz. The receive antenna with antenna aperture of 0.5m located at 1km away receives x mW of power. If the transmitting frequency changes to 20GHz, what will happen to receive power?
Find the maximum directivity of an antenna whose power density is given by $$W_{rad}= \hat{a} \frac{A_{o} \sin \theta}{r^{2}}$$ $$\frac{W}{m^{2}}$$ where $$A_{o}$$ is peak value of power density $$\theta$$ is the usual spherical coordinate and $$hat{ar}$$ is the radial unit vector
A DC series motor is driven by a chopper circuit. The supply voltage is 220 V and the duty cycle is 25%. Determine the DC voltage applied to the motor
A single-phase full-wave AC phase controller feeds power to a resistive load of 100 Ω from a 220 V, 50 Hz supply. What will be the R.M.S. output voltage at delay angles $$\alpha_{1}=\alpha_{2}=\alpha=\frac{\pi}{2}$$ of both transistors?
A half-wave rectifier is used to charge a 12 V battery through a resistance ‘R’. The input transformer is fed by 34 V AC with turns ratio 2:1. Calculate the conduction period of the diode.
Two signals $$f_{a}$$ and $$f_{b}$$ are given as input to EX-OR to measure phase difference. The average output voltage will be
In the following circuit, find the output voltage $$V_{o}$$
From the following Relative amplitude vs Frequency plot, identify the type of noise which the sections A, B, C & D depict
(i) Thermal Noise (ii) Power line pick up
(iii) Power supply (EPC) switching noise (iv)1/f noise
Y-parameter of a two port network is shown below. A 1 Ω resistor is connected to the network as shown. Find out the Y parameter of the whole network.
For the circuit shown below, $$Z_{1}=K_{1} \times \frac{(s+2)}{(s+5)}$$. Find $$ Z_{2}$$, where $$K_{1}$$ and $$K_{2}$$ are constants containing circuit element values
Following is the small signal high frequency equivalent circuit of a common source amplifier $$\frac{V_{o}}{V_{i}}$$ will be of the form
$$(K, Z_{1},a_{o},a_{1},a_{2},a_{3}$$, are constants containing circuit elements)
Phase of the transfer function of the following circuit is
The error in measurement of a dc voltmeter with input signal: 1.5 V, voltage range: 2 V, accuracy : $$\pm$$ (25 ppm of reading + 5 ppm of range) is
Consider the signal $$x(t)= \begin{cases}2\cos (t)+ \cos(2t) & t < 0\\2\sin (t)+ \sin(2t) & t \geq 0\end{cases}$$
The signal X(t) is:
The system y(t)=x(2t)+3 is
Consider the system $$R[m]=\sum_{n=0}^{N-1} Y[n] x[n-m]$$ where y[n] and x[n] are real periodic signals with period N. The above output can be obtained using
Consider the system defined by $$\frac{d^{2}y}{dt^{2}}+(a+b)\frac{dy}{dt}+ab=x(t); a>0,b>0$$ can be realized using which impulse response function
A continuous time signal has frequency content at f = 10MHz, 50MHz and 70MHz. The signal is sampled at sampling frequency of 56MHz. The frequency content of output will be
Consider the system with x(t) as input and y(t) as output. The frequency domain characteristics are shown in the figure. Which combination of A and B will give y as result?
The $$R = \frac{1}{3}$$ convolution encoder defined by transfer functions
$$H_{1}(Z) =1+Z^{-1}$$
$$H_{2}(Z) =1+Z^{-2}$$
$$H_{3}(Z) =1+Z^{-1}+Z^{-2}$$
The match filter response for given signal sampled at t = T is
Characteristic equation of H(s) is given as $$3s^{4}+2s^{3}+5s^{2}+s+2=0$$ is
Consider the feedback system
$$G(s) = \frac{K(s + 4)}{s(s + 1)} H(s) = \frac{1}{s + 2}$$
The value of gain for which system is marginally stable is
Consider the Bode plots (magnitude and phase) of two different open loop transfer functions of two unity feedback systems. The open loop transfer functions have poles in right half plane. The closed loop system formed from these open loop systems. Which of the following holds true?
The steady state response for an input X(s) = K/s to a system whose transfer function is H(s) in time domain is
$$H(s)=\frac{1}{(s+5)(s+2)}$$
Consider a closed loop stable phase locked loop system as shown in the diagram below
The system is capable of producing zero steady state error E(t) for
The modes in a reflex klystron
A dielectric is subjected to alternating electric field. The dielectric losses are proportional to
The electric field of a linearly polarized electromagnetic wave is given by $$E_{i}=\hat{a_{x}}E_{o}(x,y)e^{-jkz}$$ is incident upon a linearly polarized antenna whose electric field polarization is expressed as $$E_{a}=(\hat{a_{x}}+\hat{a_{y}}) E(r,\theta,\phi)$$.Find the polarization loss factor.
A lossless T-junction two way power divider has a source impedance, input transmission line impendence and $$\frac{o}{p}$$ port load impendence of 50 Ω. Find the output characterization impedances so that the input power is divided in a 2:1 ratio.
Following circuit implements a
The frequency of the output Y is
F : clock freq.
M : input
X : 32 bit register
Consider the output A and B with $$I_{0},I_{1},I_{2}$$ and $$I_{3}$$ as input
$$A=\overline{I_{3}} \overline{I_{2}} I_{1}+I_{3}$$
$$B=\overline{I_{3}} I_{1}+I_{3}$$
The above circuit is
The output Z =
Consider the shift register
The frequency of signal x is fs and the shift register is clocked at the positive edge of 2fs. The time offset between A and B is
The circuit is formed as shown below. The output S and C implement
What is the value of the register formed from D flip-flops using $$Q_{0},Q_{1}$$, and $$Q_{2}$$ as output $$(Q_{0},Q_{1},Q_{2})$$ after 14 cycles
The 4:1 Multiplexer implemented as
In a digital circuit the set-up time violation can be fixed by
Number of J-K flip flops in modulo 16 binary up-counter are
The solid angle subtended by the sun as viewed from the earth is Ω =$$4 \times 10^{-5}$$ steradian.
A microwave antenna designed to be used for studying the microwave radiation from the
sun has a very narrow beam whose equivalent solid angle is approximately equal to that
subtended by the sun. What is the approximate directivity, D?
A gain-standard horn is known to have a gain G = 10. It is being used to measure the gain of a large directional antenna by the comparison method. When the antenna being measured is connected to the receiver it is found to be necessary to insert an attenuator adjusted to attenuate by 23 dB in order to have the same receiver output that was observed with the horn connected. What is the gain of the large antenna?
A paraboloidal-reflector antenna is designed for operation at 3 GHz. Its largest aperture dimension is 20 feet. It is desired to build a scale model of this antenna with the largest aperture dimension scaled to 18 inches. At what frequency must this model be operated in order to have the same pattern as the full-size antenna?
An antenna has a radiation resistance of 72 Ω ,a loss resistance of 8 Ω and power gain of 16.Calculate its directivity.
The current density at the surface of a thick metal plate is 100 $$\frac{A}{m^{2}}$$ What is the skin depth if the current density at a depth of 0.0059 cm is 0.272 $$\frac{A}{m^{2}}$$?
An air filled rectangular waveguide $$R_{1}$$ is operating at the frequency 2 GHz and another air filled rectangular waveguide $$R_{2}$$ is operating at 4 GHz. The guide wavelengths of these waveguides at their respective frequencies are equal. If the cut-off frequency of waveguide $$R_{1}$$ is 1 GHz, what is the cut-off frequency of the waveguide $$R_{2}$$ in GHz?
An electromagnetic wave propagates through a lossless insulator with a velocity $$1.5 \times 10^{10} \frac{cm}{s}$$ . Calculate the electric and magnetic properties of the insulator if its intrinsic impedance is 90 $$\pi$$ ohms
A square waveguide carries $$TE_{11}$$ mode whose axial magnetic field is given by $$H_{Z}=H_{o} \times \cos (\frac{\pi x}{\sqrt{8}}) \times \cos (\frac{\pi y}{\sqrt{8}})$$ A/m where waveguide dimensions are in cm. What is the cut-off frequency of the mode?
