Practice Test: Electronics Engineering (ECE)- 15 - Electronics and Communication Engineering (ECE)

In how many ways can you place 2 white bishops on an empty chess board?

Direction: In the question below are given statements followed by some conclusions. You have to take the given statements to be true even if they seem to be at variance with commonly known facts. Read all the conclusions and then decide which of the given conclusions logically follows from the given statements disregarding commonly known facts.

Statement:

No physics is maths.

Some chemistry is maths.

All sciences are chemistry.

Conclusion:

I. No science is physics.

II. Some physics are science.

III. Some physics are chemistry.

Direction: Read the information carefully and give the answer of the following questions-

(This pie chart shows the percentage of students appear in six different exams in 2016)

(This bar graph shows the percentage of failed students which appear in these six different exams in 2016)

If in 2016, total number of failed students in exam F was 4080, then how many passed students appears in the exam B?

Direction: Two sentences with two blanks in each, followed by five alternatives with two words in each, are given. Choose that option as the answer which can fill both the blanks of both the sentences.

i. A sinking feeling of panic ________ over them and a temporary paralyzing fear engulfed them ________.

ii. Being a cleanliness freak, she ________ the floor and went down to the market only after the house was _________ clean.

Direction: Five statements are given below, labelled 1, 2, 3, 4 and 5 which are supposed to be in a logical order. A statement labelled P is given thereafter. P can replace one of the five statements such that the four statements along with P would make a coherent paragraph. You have to identify which statement should P replace and then the find out the correct sequence from the options. If the five options are in logical order and form a coherent paragraph/passage, choose the fifth option “12345”.

1) The future of Germany’s coalition government is hanging in the balance after the country’s interior minister reportedly announced his intention to resign over a migration showdown with Angela Merkel.

2) Horst Seehofer, who is also leader of the Christian Social Union, on Sunday night offered to step down from his ministerial role and party leadership in a closed-door meeting in which he and fellow CSU leaders had debated the merits of the migration deal Merkel hammered out with fellow European Union leaders in Brussels.

3) But with CSU hardliners believed to have tried to talk the combative interior minister into staying, a press conference was postponed until Monday, with Seehofer seeking to go back to Merkel in search of a final compromise.

4) At a 2am media conference, Seehofer said he had agreed to meet again with Merkel’s party before he made his decision final.

5) “We’ll have more talks today with the CDU in Berlin with the hope that we can come to an agreement,” Seehofer said.

P. Merkel said on Sunday she wanted the CDU and its Bavarian allies to continue working together.

4 identical solid spheres are melted and re-formed into a solid hemisphere. Then, the ratio of the curved surface area of the hemisphere to half of the surface area of a single sphere is -

A study of people who reduced the calories they consumed has found the strongest evidence yet that such restrictions slow down metabolism, raising hopes that a low calories lifestyle or treatments stimulating biological effects of restricted eating, could prolong health in old age. The report provides the most robust evidence to date that everything we have learnt in other animals can be applied to humans.

Which of the following argument will prove that the above conclusion is flawed?

The value of k such that the system of equation

x + ky + z = 0, x + 3y + kz = 0, 2x + y + z = 0 has non-trivial solution.

The frequency at the output of the following cascaded circuit is …………. Hz

A PCM (Pulse Code Modulation) system uses 8-bit encoder and uniform quantization. What is the maximum bandwidth(in MHz) of the low-pass input message signal for which the bit rate of the system is 20Mbps?

A super heterodyne receiver having RF amplifier is tuned to 1200 kHz, the intermediate frequency is 450 kHz. The quality factor of the tuned circuit at RF amplifier and at the mixer are same and is equal to 65. The image rejection ratio is

Simplify the given Boolean expression

A+AB'+AB'C'+AB'C'D'+AB'C'D'E'+…………………

If the skin depth is 60 µm at 3 MHz in a certain conducting medium then what will be the skin depth if the frequency is changed to 27 MHz?

Find the Standing Wave Ratio of a transmission line of characteristic impedance 80Ω is connected to a load of 100Ω.

Consider the following continuous time signal x(t)

If C_k is the complex Fourier series coefficient of signal x(t). Then the value of |C₂| will be

The circuit shown in the figure below is in steady state when switch is closed at t = 0, then the value of

Characteristic equation of a system having unity feedback is

(s + 1)(s - 2)+ k(s - 3)(s + 4). The system is then which of the following?

Consider a spatial curve in 3D space given on parameters form by

X = t

Y = 1

Z = 3t/π in 0 ≤ t ≤ π. The length of the curve is

The modified work function of N-channel MOSFET is -0.8V. The effective positive charge at the Semiconductor oxide layer interface is 9.8 x 10^-5 C/m² and the oxide capacitance is 300 μF/ m², then calculate the flat band voltage.

In the voltage controller circuit shown in the figure (assume that op-amp is ideal). The BJT has V_BE = 0.7V & β is very large and V₂ = 4.7V. For a regulated output of 9.4V, the value of R (in kΩ) is

Consider a lossless antenna with a directive gain of +6db. If 1mW of power is fed to it the total power radiated by the antenna will be

The output voltage V_o(in mV) of the circuit shown in figure

For a given P⁺ - N Si junction diode with N_D = 10¹⁵ cm^-3 and _ni = 10¹⁰ cm^-3 and e = 8.85 × 10^-14 C²/N-cm³. Find the electric field at the midpoint of the depletion region on the n-side. (let reverse bias voltage = 100V)

The divergence of the vector

For the voltage amplifier circuit shown in the figure, A_v is very high. Also R_S = 1mΩ, R_L = 1kΩ R₁ = 1 kΩ and R₂ = 1mΩ

Then what is the value of |V_o/V_s| = ?

The value of d/dt x(t) at t = 1.5 for x(t) = u(t) + r(t) - 2r(t - 1) + r(t - 2) - u(t - 2) is

Consider an angle modulated signal X(t) = 10.cos [10⁸ πt + Sin 2π 10³t]

The maximum frequency deviation is ________kHz?

With G(s) = k/(s+3)⁵. Find kmax for stability.

k =

For the circuit using op-amp -741 with unity gain frequency of 1 MHz. The overall 3 -dB frequency is ____?

Given that D = z⋅ρ cos²⁡ϕa₂c/m², Calculate the charge density at (1, π/4, 3) and then the total charge enclosed by the cylinder of radius 1m with −2 ≤ z ≤ 2m is?

Let c be triangle path connecting the points (0, 0), (4, 4) and (0, 4) in the counter clock wise direction then,

For the transfer function

The resonance peak magnitude is

The residue of the function

For the lattice circuit shown in figure, Z_a = 20Ω and Z_b = 10Ω. The value of open circuit impedance parameter Z_{12 i}s ____ Ω ?

For given circuit, with R = 1 kΩ and C = 1 μF and also R₁ = R₂. The output frequency is ____ kHz. (Assume ideal opamp)

A photo-detector circuit shown in figure. The photo-diode has an active area of 10⁺² cm² and sensitivity of 0.55 A/W. When light of intensity 10mW/cm² falls on the photo-diode, the output voltage V_O is ___ volt.

Study the standard negative feedback configuration with G(s) Find the number of clockwise encirclements of (-1, 0) in the Nyquist of the Loop transfer function G(s) H(s) will be

A second order process having transfer function is cascaded with a standard PD controller in unity feedback configuration. If the closed loop system have velocity error constant K_V = 300 and damping ratio ζ = 0.6, then the value of controller gain (k_P) is

Which of the following signal is obtained on integrating ramp signal?

A unity feedback control system has an open loop transfer function.

The value of system gain K for which all the roots are equal is _______.

For a Si, one sided abrupt junction with N_A = 2 × 10¹⁹/cm³ & N_D = 8 × 10¹⁵/cm³ & n_i = 9.65 × 10⁹/cm³ The junction capacitance at zero bias is ______(in mF/cm²). Given,ϵ_r = 11.7

In an n-channel MOSFET, drain is shorted to the gate so that V_GS = V_DS. And

V_T = 1V. If the drain current I_D is 1 mA for V_GS = 2V then for V_GS = 3V, I_D (in mA) is

A semiconductor of thickness 0.5μm is illuminated with monochromatic light of hϑ = 2eV, and the absorption coefficient of semiconductor α = −5 × 10⁻⁴cm⁻¹. If the incident power is 10mW (Assume semiconductor has perfect quantum efficiency) then number of photons given from recombination events per second is photons/sec

In a 8085 microprocessor, the register which holds address of the next instruction to be fetched is

Calculate Zth across the terminals A and B:

The response of a system at zero initial conditions and non-zero input is called ________.

Following the state diagram shown clocked sequential circuit:

How many states the sequential circuit has?

Consider the following circuit. A = a₂a₁a₀ and B = b₂b₁b₀ are three bit binary numbers input to the circuit. The output is Z = z₃z₂z₁z₀. R0, R1 and R2 are registers with loading clock shown. The registers are loaded with their input data with the falling edge of a clock pulse (signal CLOCK shown) and appears as shown. The bits of input number A, B and the full adders are as shown in the circuit. Assume Clock period is greater than the settling time of all circuits.

For 8 clocks pulses on the CLOCK terminal and the inputs A, B as shown, obtain the output Z (sequence of 4-bit values of Z). Assume initial contents of R0, R1 and R2 as all zeros.

A = 110 011 111 101 000 000 000 000

B = 101 101 011 110 000 000 000 000

Clock No 1 2 3 4 5 6 7 8

Find by double integration the volume of the solid generated by revolving the ellipse about the x-axis.

Calculate the value of

Consider the following differential equation dy/dx = -x+1

If y (2) = 1 then the value of y (2.2) using Runge- Kutta third order method is

The value of integral c∮(yzdx + zxdy + xydz) where c is the curve x² + y² = 1 and z = y² is

Consider the two port network shown below

Consider the 2 port circuit given below

Hybrid parameter h₁₂ for the circuit is _____.

For the opamp biasing shown in figure, it was found experimentally even at zero bias the current flowing into positive terminal is 15nA and current flowing into negative terminal is 10nA. If the output voltage of op-amp is 8mV. The value of feedback resistance Rf is__________.

Assume (R_f ≫ R). R = 0.5 kΩ

The input-output relationship of a causal stable LTI system is given as y[n] = αy[n - 1] + βx[n].

If the impulse response h[n] of this system satisfies the condition the relationship between α cond⁡ β is

The Fourier transform of continuous time signal X(t) = 3cos(10t) + 4sin(10t) is

If the Nyquist rate for x(t) is ω₀, what will be the Nyquist rate for x(3t) and x(t/3)?

Find the systems response to the input x[n] = u[n]| if the unit impulse response h[n] of a DT LTI system is

Consider the speed control system of figure below where in the inner loop corresponds to motor back emf. The controller is an integrator with gain K observe that the load is inertia only.

Determine the value of k for which steady state error to unit ramp input (V_r = 1/s²) is less than 0.01 rad/sec.

Find the capacitor voltage VC at t = 1msec if switch is closed as t = 0. Assume capacitor initially uncharged and op-amp is not saturated.