Practice Test: Electronics Engineering (ECE)- 9

The fourier sine transform of 

For a series RLC circuit, which one of the following statement is NOT correct

The circuit shown above is initially relaxed. At t = 0, the switch is closed. At t = 1 sec, the current i(t) is

The concentration of minority carriers in an extrinsic semiconductor under equilibrium is

An N-channei JFET has a pinch-off voltage of -4.5V and l_DSS = 9mA. At what value of V_Gs will I_D equal to 3 mA

The ratio of the mobility and the diffusion co-efficient in a semiconductor has units

The input resistance R_i of the amplifier shown is

The cascade amplifier configuration is

The following circuit functions as

For the circuit shown in figure, if the clock frequency is 10KHz, the frequency of the waveform at the output Q is _____________KHz

The Boolean function y = AB + CD is to be realized using only 2-input NAND gates. The minimum number of gates required is __________

The trigonometric fourier series for the wave form shown below contains

Let x(n) and y(n) represents the input and output of a discrete-time system, which one of the following is not a causal system.

The average value (d.c) for the waveform shown below is

Consider an angle modulation signal x(t) = 4 [2π x 10^s t + 3 sin(6000π t) + 4 cos(8000πt)]v.

The average power of x(t) is

For a message signal m(t) = cos(2πfmt) and carrier of frequency f_C, which of the following represents a single side band (SSB) signal

The capacitor of Gaussian channel of band width 4KHz, with noise PSD 10^-9 wHz. When the signal Energy is 0.1. J.

The transfer function of a system is given by  The system is

A 555 astable oscillator with R₁ = 40 kΩ, R₂ = 120 kΩ and C = 4.0 μF will oscillate at

The magnetic field intensity vector of a plane wave is given by   = 10sin (5000t + 0.004x + 30)  where denotes the unit vector in y direction. The wave is propagated with a phase velocity of

In the wave equationwhich term is responsible for attenuation of the wave?

Match each differential equation in Group - I to its family of solution curves from Group - n.

dr where 'c' is curve y = 4x² in xy plane from (0, 0) to (1,4).

For the matrix one of the eigen values of the matrix P is 3, which of the following is

Consider the two independent random vanabies X and Y with identical distnbutions. The variables X and Y take the values 0, 1, 2. 3. 4 with respective probabilities  What is the conditional probability P(X + Y = 4/X - Y = 0)?

The driving point impedance of the foilowing network is given by The component values are

The thevemn equivalent impedance Z_th between the nodes P and Q is the following circuit is

The h-parameters of the circuit shown is figure is

For the transistor shown above, R_c = 10 K, h_fe = 50, h_oe 25 x 10^-6 , all capacitors are short circuited at the signal frequency, the current gain is given by

The circuit using a BJT with β = 50 and V_BE = 0,7 V is shown is figure. The base current l_B and collector V_C are respectively.

For the amplifier shown above, given r_d = 20 kΩ, l_Dss = 10 mA, V_p = -8 V Z_i and Z_o of the circuit are respectively.

The above amplifier is a

The output of the above amplifier is

For the circuit shown in figure, the Boolean expression for the output Y interms of inputs P, Q, R and S is

An X-Y flip flop whose characteristic table is given below is to be implemented using a J-K flip flop

This can be done by making _

The following program is written for an 8085 microprocessor to add two bytes, located at memory addresses 1FFE and 1FFF

LXIH, 1FFE
MOV B, M
INR L
MOV A, M
ADD B
INR L
MOV M, A
XORA

On completion of the execution of the program the result of addition is found.

Consider the rectangular pulse shown in figure, its fourier transform is

The R.O.C of the Z-transform of the discrete time sequence 

Consider a continuous time signal x(t)  

A state model of a system is characterized by the differential equation  Its transfer function will be

A unity feedback system has an open loop transfer Its damping ratio and peak over shoot will be

The block diagram shown in figure, given a unity feed back closed loop control system. The steady state error in the response of the above system to unit step input is_________________________ %

A uniform plane wave has a wavelength of 2 cm in free space and 1 cm in a perfect dielectric. What is the relative permittivity of the dielectric?

Q.

Consider an n-type silicon bar of length 1 cm with electron concentration of 10¹⁶, the charge of electron is 1.6 x 10^-19 C and mobility is 3800cm²/V-s at 300 K. The conductivity of silicon is

If a potential of 5V is applied across the bar. the current density is

A carrier is phase modulated (PM) with frequency deviation of 10 KHz.by a single tone frequency of 1 KHz.lf the single tone frequency is increased to 2 KHz, assuming that the phase deviation remains unchanged

Q. 

The bandwidth of the PM signal is

A carrier is phase modulated (PM) with frequency deviation of 10 KHz.by a single tone frequency of 1 KHz.lf the single tone frequency is increased to 2 KHz, assuming that the phase deviation remains unchanged

Q. 

With single tone frequency fm is 1 KHz, what is the max frequency deviation.

A plane wave of frequency 1 MHz is traveling in a large block of copper (σ = 5.8 x 10⁷, ε_r ≈ 1, μr ≈ 1).

Q.

The phase constant is

A plane wave of frequency 1 MHz is traveling in a large block of copper (σ = 5.8 x 10⁷, ε_r ≈ 1, μr ≈ 1).

Q. 

The wave speed in copper at this frequency is

The unmodulated carrier power of an AM wave is 8 KW and rises to 10 KW after modulation. The modulation index is

If another sine wave is modulated with a modulation index of 0.5 with the above system, the total power is

Directions for questions 56 and 57: Fill in the blanks with the most appropriate word from the choices.

According to educationist Sir Ken Robinson, in thecoming years, _____ in education would be asimportant as literacy.

With the economy back on track, manufacturers andretailers are set to cash in on the festive  ____ this month.

Directions for question 58: Which of the options is the closest in meaning to the word given in capitals?

ODIUM

Directions for question 59: The question below consists of a pair of related words followed by four pairs of words. Select the pair that share a similar relationship as the original pair.

PATIENT: HOSPITAL

In a queue ten persons are standing ahead of Bhonsle, five persons are standing behind Mane. Six persons are standing between Bhonsle and Mane. What is the position of Mane from the front of the queue?

Machines P, Q and R can do a piece of work in 20, 30 and 60 days respectively. Machines P, Q and R start the work together. Machine P goes out of order after 5 days. After 3 more days machines Q and R also go out of order. Machine P got repaired by then and it completes the remaining work. What portion of the total work did machine P do?

P and Q are two points, 10 km apart. Anand started from P towards Q and at the same time, Ashok started from Q towards P. They crossed each other after 1 hour. After that, Anand reduced his speed by 2 kmph and Ashok increased his speed by 2 kmph. They reached their destinations simultaneously. Find Anand's initial speed (in kmph).

A vessel has 10 ml of a solution of milk and water containing 20% milk, x ml of milk was added to the vessel to reverse this ratio, y ml of water was then added to the vessel to reverse the ratio once again. Find x + y.

Four dishes - Fried rice, Daal,- Panneer and Gulabjamun are placed on a table in a row. One among these dishes is Tasty and healthy. We know the following information about them.

(i) Neither of the two dishes adjacent to paneer is healthy.
(ii) Gulabjamun is at the end of the row.
(iii) Daal is adjacent to only one dish,

which is not tasty.Which dish is healthy and tasty?

Directions for question 65: From the options pick the best summary of the original passage.

Inspite of data indicating that the US economy has been modestly rebounding, there is a growing fear that it is simply a lull on the way to worse times ahead. That fear, rooted in history, is the product of both legitimate concern and ugly political opportunism. For now, the sea of data is sending mixed signals: on the negative side employment is weak and showing few signs of strengthening, consumers are spending at a reduced pace, states are facing severe budget problems and credit remains tight. On the plus side, corporate earnings are soaring, job loss has slowed, production and productivity are up, the financial system has stabilized, and GDP has been expanding for almost a year.