Practice Test: Electronics Engineering (ECE)- 13 - Electronics and Communication Engineering (ECE)

Refer the below data table and answer the following Question.

If the GDP of the country was $8 trillion at the end of 2011, what was it at the beginning of 2013?

Select the most appropriate synonym of the given word.

Solicit

In the following question, a sentence is given with a blank to be filled in with an appropriate word. Select the correct alternative out of the four and indicate it by selecting the appropriate option.

The little boy ran ____ fast that he was ____ for breath.

Select the most appropriate option to fill in the blank.

Although his brother is blind, he is very fast _________ calculations.

The monthly salaries of A. Band C are in the ratio 2 :3 :5. If C's monthly salary is Rs. 12,000 more than that of A, then B's annual salary is

Mathew told his friend Sham, pointing to a photograph, “Her father is the only son of my mother.” The photograph is of whom?

Round-trip tickets to a tourist destination are eligible for a discount of 10% on the total fare. In addition, groups of 4 or more get a discount of 5% on the total fare. If the one-way ticket fare of the trip for single person is Rs 100, a group of 5 tourists purchasing round-trip tickets will be charged Rs____.

In the following figure, the J and K inputs of all the four Flip-Flops are made high. The frequency of the signal at output Y is

Determine V_o (in Volts) in the given network.

Consider the lossless transmission line circuit shown in the figure, The voltage standing wave ratio on 50 Ω line is given by

The output of a continuous-time, linear time-invariant system is represented by T{x(t)} where x(t) is the input signal. A signal z(t) is called eigen-signal of the system T, when T{z(t)} = Y z(t) , where Y is a complex number, in general, and is called an eigen-value of T. Assume the impulse response of the system T is real and even. Then which of the following statements is TRUE?

Given x(t) = e^−tu(t). Find the inverse laplace transform of e⁻³sX(2s).

For the given signal, x(t) = 3 cos 80πt, determine the sampling frequency(in Hz) at which aliasing will take place.

Find the differential equation of the system described by the transfer function given as:

Let the state transition matrix of a system be given as

Then which of the following is equal to φ^-1(t)

The built-in potential of an abrupt p-n junction is 0.75 V. If its junction capacitance (Q) at a reverse bias (V_R) of 1.25 V is 5 pF, the value of C_J (in pF) when V_R = 7.25 V is________.

A Si Solar cell has short-circuited current of 100 mA and open-circuit voltage of 0.7 V under full illumination. If the fill factor is 0.71 then the Maximum power delivered (in mW) to load by this cell is

Assume electronic charge q = 1.6×10⁻¹⁹C, kT/q = 25mV and electron mobility μ_n = 1000cm²/V−s. If the concentration gradient of electrons injected into a P-type silicon sample is 1×10²¹ cm⁴, the magnitude of electron diffusion current density (in A/cm²) is _________.

In an abrupt p-n junction, the doping concentrations on the p-side and n-side are NA = 9 X 10¹⁶ /cm³ and N_D = 1 X 10¹⁶ /cm³ respectively. The p-n junction is reverse biased and the n-side depletion width is 3μm. The depletion width on the p-side is

The voltage gain of an amplifier is 100. A negative feedback is applied with β = 0.04. The overall gain of the amplifier is:

For common emitter input characteristics V_CE is 6V and V_BE is changed from 0.32 to 0.8V also base current changes from 40μA to 60μA, then by using the given data calculate the input impedance (in KΩ) kept V_CE constant.

Consider two resistors of 50 kΩ and 100 kΩ at room temperature of 27ºC. These resistors are passing a signal of bandwidth 50 kHz. Let N₁ and N₂ be the noise voltage generated while operating in series and parallel configuration, respectively. Determine N₁ and N₂.

A receiver has been operating at 290 K and receiving a signal of bandwidth 400 kHz. The amplifier used in the receiver has an average output resistance of 1.5 kΩ. This will lead to Johnson noise voltage of ________ μV.

An amplifier operating over the frequency range of 18 to 20 MHz has a 10kΩ input resistance. The RMS noise voltage at the input to the amplifier at ambient temperature is (assume Boltzman’s constant

The return loss due to a 150W cable terminated by a 100W load is _______________ (in dB)

What is the maximum torque (in Nm) on a square loop of 200 turns in a field of uniform flux density of 1 Wb/m². The loop has 15cm side and carries a current of 5A.

Consider the following sequential circuit consisting of 2 J-K flip flops and D flip flop :

The Mod value for this counter is_____________.

The maximum number of Boolean expression that can be formed for the function f(x,y,z) satisfying the relation

When two 8-bit numbers A₇…A₀ and B₇…B₀ in 2’s complement representation (with A₀ and B₀ as the least significant bits) are added using a ripple-carry adder, the sum bits obtained are S₇….S₀ and the carry bits are C₇…..C₀. An overflow is said to have occurred if

If then z lies on where w and z are complex numbers

Two linearly independent solutions of the homogeneous equation, x²y” + xy’ + y = 0 , are

In a broadcast super heterodyne receiver the quality factor of antenna coupling circuit is 150, if the intermediate frequency is 455 KHz, then the image rejection ratio at 20 MHz is.

What is the expression for the minimum conductivity σ_min?

A 700 mW maximum power dissipation diode at 25 °C has 5 mW/oC de-rating factor. If the forward voltage drop remains constant at 0.7 V, the maximum forward current at 65 °C is

A Ge sample at room temperature has intrinsic carrier concentration, n = 1.5 × 10¹³ cm^-3 and is uniformly doped with acceptor of 3 × 10¹⁶ cm^-3 and donor of 2.5 × 10¹⁵ cm^-3 . Then, the minority charge carrier concentration is:

What is the image rejection ratio when a super heterodyne receiver with quality factor of 50 is tuned with fs = 800 KHz and local oscillator frequency is 1250 KHz.

The transistor in the amplifier circuit shown in figure is biased at I_C = 1 mA. Use V_T = 26 mV , β = 200,r_b = 0 and r₀ → ∞

What is the required value of C_E for the circuit to have a lower cut off frequency of 10Hz is

A shooter P hits the target with probability of 1/2 but is allowed only one shot whereas the shooter Q hits with probability of 1/4 but takes two shots. A shooter R hits with probability of 1/8 and is allowed five shots. In a competition, it is probable that:

Let A ϵ M₃ (R) be such that det (A-I) = 0, where I denotes the 3 x 3 identity matrix. If the trace of A = 13 and det A = 32, then the sum of squares of the eigen values of A is _________.

An angle modulated wave is given as follows x(t) = 50 cos⁡[2π × 10⁶t + 0.001 cos⁡ 2π(500)t]

Find the bandwidth of the signal and the instantaneous frequency of the signal at t = 2ms respectively.

The inverse fourier transform of e^-6ωu(ω) + e^6ωu(ω)

Consider the state-variable model of the system given by

The transfer function of the system is given by

Consider the signal s(t) shown in the figure, which is the output of an AWGN (Additive White Gaussian Noise) channel with two-sided noise PSD (Power Spectral Density) of 0.5W/Hz. If the signal is given as an input to a matched filter to s(t), then the slope of the output signal for 2V.

Constellation diagram of a binary modulation scheme is given below.

The two equiprobable symbols shown in the diagram are transmitted through an AWGN (Additive White Gaussian Noise) channel with one-sided PSD (Power Spectral Density) of 0.5W/Hz. If the correlator receiver with optimum threshold detection is used at the receiver end, then the bit error rate (BER) of the system is given by,

Find the resonant frequency (in Hz) of the circuit given below:

[Write the Answer upto two decimal point]

If V_c(t) = 4 cos (10⁵t) Volts in the circuit given below, then find the value of V_z

The Figure shows two signals x(t) and h(t) as

Which of the waveform in the options corresponds to denotes convolution.

Consider the causal discrete time system shown below, minimum magnitude of K for which system become unstable is

Consider a discrete time periodic signal of period N = 6 of whose one period is given as follows

The discrete time Fourier series coefficients of x[n] is given as

In the given oscillator circuit, find the values of C₁ and C₂ that would make the bridge balanced

A speech signal, band limited to 5 KHz with peak to peak between +10 V to – 10 V and the signal is sampled at Nyquist rate and the bits 0 and 1 are transmitted using bipolar pulses. What is minimum bandwidth for distortion free transmission ….

Two identical transistors are cascaded as follows with β = 100. The overall voltage gain would be

A radio antenna pointed in a direction of the sky has a noise temperature of 50 kHz. The antenna feeds the received signal to the preamplifier which has a gain of 35 dB over a bandwidth of 10 MHz and a noise figure of 2 dB. Then the noise power at output of the preamplifier is _____(pW)

A load of 1 KΩ is connected to a diode detector which is shunted by a 10kpF capacitor. The diode has a forward resistance of 1 Ω. The maximum permissible depth of modulation, so as to avoid diagonal clipping and modulating signal frequency of 10kHz will be

An n-type silicon sample is uniformly illuminated with light which generates 1020 electron hole pairs per cm³ second. The minority carrier lifetime in the sample is 1 μs. In the steady state, the hole concentration in the sample is approximately 10x, where x is an integer. The value of x is___

In an air-filled rectangular waveguide with a = 2.286cm and b = 1.016cm , the y-component of the TE mode is given by

Then the intrinsic impedance (in Ω) is

A coaxial capacitor of inner radius 1 mm and outer radius 5 mm has a capacitance per unit length of 172 pF/m. If the ratio of outer radius to inner radius is doubled, the capacitance per unit length (in pF/m) is ___.

The intermediate frequency of an AM superheterodyne receiver is 460kHz and the local oscillator frequency {f_LO) of the mixer is set at the higher of the two possible values, such that f_LO > fc always. If the carries frequency {f_C of the receiver signal is 700kHz, then the carrier frequency of the corresponding image signal will be kHz

Which of the above statements is correct?

Pick out the 'TRUE' from the following?

A dc voltage of 10 V is applied across an n-type silicon bar having a rectangular cross-section and a length of 1 cm as shown in figure. The donor doping concentration ND and the mobility of electrons μs are 10¹⁶ cm^-3 and 1000 cm²V^–1s^–1, respectively. The average time (in μs) taken by the electrons to move from one end of the bar to other end is__________

Assuming that flip-flops are in reset condition initially, the count sequence observed at QA in the circuit shown is