Practice Test: Electronics Engineering (ECE)- 10 - Electronics and Communication Engineering (ECE)

If the average of squares of 10 observations is 34 and their average is 5, then their standard deviation is ______   

The state equation of the circuit shown in figure is

The dual of the network shown below will be

An unregulated power supply of 25 V is connected to zerer diodes and p - n diodes (cut in voltage 0.7V) as shown in figure, then the values of x and y, 7 are? 

The load lines were drawn for the circuit collector Resistance Re = x, and y. From the graph we can conclude that 

A silicon diode has saturation current of 6 nA, at 25°C. The saturation current at 100°C is

The CMRR of the differential Amplifier shown Here is

The OP-Amp circuit shown acts as

The base of the number system, in which the operation is correct?

The minimized Boolean expression of 'F is 

A mod 16 counter with Asynchronous, Active low clear input is arranged as shown in figure. It works like a

The discrete fourier series coefficients of 

The z transform of na^n-1 u[n] given by

if y(t) = x(t) * h(t), then x(t -t₁) *h (t- t₂) is

A control system is represented by signal flow graph as shown, C(s) is the output, then

Range of 'k' for which the feed back system is stable, s(s² + s + 1) (s + 4) + k = 0

Band width of an FM system is 180 KHz, when audio frequency 15 KHz is FM modulated, The frequency deviation is _______ KHz

Propagation delay for a 1 km optical fibre cable witha core index of refraction as 1.5 is

A narrow band signal occupying a frequency range of nfo to (n + 1) f₀ is to be sampled. The maximum sampling rate is

A transmission line is distortion less if

Distilled water at 25°c is characterized by σ = 1.7 x 10^-4 mho/m, and s = 78ε₀. at freauencv of 3GHz. Its loss tangent tan

The depth of penetration of electromagnetic wave in a medium having conductivity σ at a frequency of 1MHz is 25 cm. The depth of penetration at a frequency of 4MHz will be_____ cm

There are three bags each containing five white balls and two black balls constituting group A and two bags each containing one white ball and four black balls constituting group B. A bag is randomly selected and a ball is drawn from it It was found to be a black ball. What is the probability that the b.alf is drawn from a bag in group A?

Find a real root of the equation x³ + 2x - 1 = 0.

Solve the differential equation

The value of the Fourier cosine expansion of the function f(x) = x in the interval

The voltage V across the Resistor ‘R’ in the circuit is

At 300k, for a diode current of 2 mA, a certain germanium diode requires a forward bias of 0.1435V, where as a certain Silicon diode requires a forward bias of 0.71 BV. Then the closest approximation of the ratio of reverse saturation current in germanium diode to that of silicon diode is

A particular green LED emits light of wavelength 4970 A°. The energy band gap of the semiconductor material used in LED is (plank’s constant = 6.626 x 10^-34 J -s)

When the gate to source voltage (V_Gs) of MOSFET with threshold voltage of 400mV, working in saturation is 900mV, the drain current is observed to be 1mA. Neglecting the channel width modulation effect and assuming that the MOSFET is operating at saturation, the drain current for an applied V_Gs of 1500mV is___ mA

If the op-Amp in the figure has an input offset voltage 3mV, and an open - loop voltage gain of 10.000 then V₀ will be

The Dual of the exclusive OR gate is

The equation F = AB¹CD¹ + A¹BCD¹ + AB¹C¹D + A¹BC¹D can be minimized to

The inputs of MUX l₃l₂l₁l₀ those should be connected for the arrangement shown in circuit that works as per the function table are?

A 4 bit right shift, shift Register is initially loaded with 1001, the serial input 110101 (LSB with first clock pulse) is given to the register, the contents of register after 5-clock cycles are

Given Laplace transforms,  is

A system with an input x(t), and output y(t) is described by the relation y(t) = tx(t). The system is

Match the following

The gain margin (in dB) of a system having the loop transfer function G(s) 

Consider the points s₁ = - 3 + j4, and s₂ = - 3 - j2, in the S - plane, then for a system with the open loop transfer function   

For the system describee oy the equation 

if the control signal is giver by u = [- 0.5 - 3 - 5] x + v, the eigen values of dosee oop system will be?

In an FM system a carrier of 100MHz is modulated by a sinusoidal signal of 5KHz. The Bandwidth by carson's approximation is 1MHz. If y(t) = (modulated wave from)T then by using carson's approximate, the band width of y(t) around 300MHz, and spacing of Spectral components are, respectively

Four independent messages have bandwidths of 100Hz, 100Hz, 200Hz, 400Hz respectively, each one is sampled at the Nyquist rate and the samples are time division multiplexed (TDM) and transmitted. The transmitted sample rate (in Hz) is    

In air, a lossless transmission line of length 50 cm, with L = 10 μH/m, c = 40 pF/m is operated at 25 MHz. Its electrical path length is

The following series RLC circuit with zero initial conditions is excited by a unit Impulse functions

Q. 

for t > 0, the output V_c(t) is

The following series RLC circuit with zero initial conditions is excited by a unit Impulse functions

Q. 

for t > 0, the voltaqe across the resistor is

Consider the OD-Amo circuit shown in figure

Q.

The transfer function V₀(s)/V_i (s)is 

Consider the OD-Amo circuit shown in figure

Q. 

 the minimum and maximum values of(in radians) are respectively

X(t) is a random process with a constant mean value of 0 and the auto correlation function R_x(t) = 4[e^-0.2|t| + 1]

Q. 

Let x be the gaussion random variable obtained by sampling the process at t = t_i and
The probability that  is

X(t) is a random process with a constant mean value of 0 and the auto correlation function R_x(t) = 4[e^-0.2|t| + 1]

Q. 

Let y and z be the random variables obtained by sampling x(t) at t = 2, and t = 4, respectively, let w = y - z. The variance of w is

An antenna located on the surface ot a nat eartn, transmits an average power of 150 kW, Assume that all the power is radiated uniformly over the surface of hemisphere with antenna at the centre

Q.

The time average pointing vector at 50 km is

An antenna located on the surface ot a nat eartn, transmits an average power of 150 kW, Assume that all the power is radiated uniformly over the surface of hemisphere with antenna at the centre

Q. 

maximum electric field at that locations is

Directions for questions 56 and 57: Fill in the blanks with the right option from the given choices.

Q.

The illegitimate war on Iraq____the country andseverely eroded its capacity to manage its future.

The human auditory system perceives soundfrequencies ranging _____20 H_z through 20000 H_z

Directions for question 58: From the choices, pick the word that is closest in meaning to the head word.

CANDOUR

Directions for question 59: The question below consists of a pair of related words followed by four pairs of words. Select the pair that expresses the same relation as in the original pair.

Pointing at a photograph, Saradhy said to Thomas, “the person in the photograph is my wife’s only daughter's brother’s paternal grandfather’s only daughter’s husband and your mother's father-inlaw's only son. How is Saradhy related to Thomas?

The average weight of all the students of classes I and n equals the average of the average weight of the students of the two classes. There are twice as many students in class II as in class I. The sum of twice the average weight of student's in class I and the average weight of the student of class II is 60 kg. Find the average weight of class I (in kg).

The tables below indicate the number of children in four schools P, Q, R and S in the high school section, i.e., classes 8^th, 9^th and 10^th in 2007 and 2008.

In which school, did the total strength in the high school section, decrease from 2007 to 2008?

In a town, the population of males decreased by 25% from 2001 to 2002. The population of females increased by 20% in this period. If females formed of the population in 2002, what percentage of the population in 2001 were males?

Each of A, B, C and D wore a shirt from the four shirts available. Each of these shirts is of one of the colours black, white and green. It is known that,

A wore black or white shirt.
B wore black or white or green shirt.
C wore black or green shirt.
D wore green or white or black shirt.

Which of the following information can definitely give the colour of the shirt worn by each of them?

Directions for question 65: Four alternative summaries are given below the text. Choose the option that best captures the essence of the text.

It is one of the tritest observations about India that cricket and Bollywood are our abiding passions. As it turns out, the sentiment is untrue as nothing galvanises us or moves the mob monster to frenzy like politics does. It is the beast that devours our movies and games in one gulp and makes them its own, the progenitor of passionate debates that begin at tea stalls and continue in swish living rooms.