GATE ECE 2009 PYQ

In the following a stable multivibrator circuit, which properties of depend on ?

A small signal source is applied to a transistor amplifier as shown below. The transistor has = 150 and = 3W. Which expression best approximate (t)

In the circuit shown below, the op-amp is ideal, the transistor has VBE = 0.6 V and = 150. Decide whether the feedback in the circuit is positive or negative and determine the voltage V at the output

In the circuit below, the diode is ideal. The voltage V is given by

Consider for CMOS circuit shown, where the gate voltage of the n-MOSFET is increased from zero, while the gate voltage of the p -MOSFET is kept constant at 3 V. Assume, that, for both transistors, the

A message signal given by is amplitude-modulated with a carrier of frequency to generate What is the power efficiency achieved by this modulation scheme ?

A white noise process X(t) with two-sided power spectral density is input to a filter whose magnitude squared response is shown below. The power of the output process Y(t) is given by

For a message signal and carrier of frequency , which of the following represents a single side-band (SSB) signal ?

A communication channel with AWGN operating at a signal to noise ration and bandwidth B has capacity . If the SNR is doubled keeping constant, the resulting capacity is given by

The amplitude of a random signal is uniformly distributed between -5 V and 5 V. If the positive values of the signal are uniformly quantized with a step size of 0.05 V, and the negative values are uni

If the power spectral density of stationary random process is a sine-squared function of frequency, the shape of its auto correlation is

A discrete random variable X takes values from 1 to 5 with probabilities as shown in the table. A student calculates the mean X as 3.5 and her teacher calculates the variance of X as 1.5. Which of the

The feedback configuration and the pole-zero locations of are shown below. The root locus for negative values of k , i.e. for , has breakaway/break-in points and angle of departure at pole P (with res

The Nyquist plot of a stable transfer function G(s) is shown in the figure are interested in the stability of the closed loop system in the feedback configuration shown. The gain and phase margins of

Consider the system with and where p and q are arbitrary real numbers. Which of the following statements about the controllability of the system is true ?

The magnitude plot of a rational transfer function G(s) with real coefficients is shown below. Which of the following compensators has such a magnitude plot ?

The unit step response of an under-damped second order system has steady state value of -2. Which one of the following transfer functions has theses properties ?

What are the counting states ( ) for the counter shown in the figure below

Two products are sold from a vending machine, which has two push buttons P1 and P2. When a buttons is pressed, the price of the corresponding product is displayed in a 7-segment display. If no buttons

If X=1 in logic equation , then

Refer to the NAND and NOR latches shown in the figure. The inputs ( ) for both latches are first made (0, 1) and then, after a few seconds, made (1, 1). The corresponding stable outputs ( ) are

The full form of the abbreviations TTL and CMOS in reference to logic families are

What are the minimum number of 2-to-1 multiplexers required to generate a 2-input AND gate and a 2-input Ex-OR gate

Two infinitely long wires carrying current are as shown in the figure below. One wire is in the y-z plane and parallel to the y-axis. The other wire is in the x-y plane and parallel to the x-axis. Whi

If a vector field is related to another vector field through , which of the following is true? (Note : C and refer to any closed contour and any surface whose boundary is C.)

A transmission line terminates in two branches, each of length , as shown. The branches are terminated by 50 loads. The lines are lossless and have the characteristic impedances shown. Determine the i

Which of the following statements is true regarding the fundamental mode of the metallic waveguides shown ?

A magnetic field in air is measured to be What current distribution leads to this field ? [Hint : The algebra is trivial in cylindrical coordinates.]

Consider the following two statements about the internal conditions in a n-channel MOSFET operating in the active region. S1 : The inversion charge decreases from source to drain. S2 : The channel pot

The ratio of the mobility to the diffusion coefficient in a semiconductor has the units

In an n-type silicon crystal at room temperature, which of the following can have a concentration of ?

Consider a silicon p-n junction at room temperature having the following parameters: Doping on the n-side = Depletion width on the n-side = 0.1 m Depletion width on the p -side = 1.0 m Intrinsic carri

In a microprocessor, the service routine for a certain interrupt starts from a fixed location of memory which cannot be externally set, but the interrupt can be delayed or rejected. Such an interrupt

If the transfer function of the following network is The value of the load resistance is

A fully charged mobile phone with a 12 V battery is good for a 10 minute talktime. Assume that, during the talk-time the battery delivers a constant current of 2 A and its voltage drops linearly from

The time domain behavior of an RL circuit is represented by . For an initial current of , the steady state value of the current is given by

The switch in the circuit shown was on position a for a long time, and is move to position b at time . The current for is given by

An AC source of RMS voltage 20 V with internal impedance feeds a load of impedance in the figure below. The reactive power consumed by the load is

In the interconnection of ideal sources shown in the figure, it is known that the 60 V source is absorbing power. Which of the following can be the value of the current source I ?

In the circuit shown, what value of maximizes the power delivered to ?

A function is given by . Which of the following is true ?

An LTI system having transfer function and input is in steady state. The output is sampled at a rate rad/s to obtain the final output {y(k)}. Which of the following is true ?

The ROC of z -transform of the discrete time sequence is

Consider a system whose input and output are related by the equation where h(t) is shown in the graph. Which of the following four properties are possessed by the system ? BIBO : Bounded input gives a

A system with transfer function H(z) has impulse response defined as h(2)=1, h(3)=-1 and h(k)=0 otherwise. Consider the following statements. S1 : H(z) is a low-pass filter. S2 : H(z) is an FIR filter

The 4-point Discrete Fourier Transform (DFT) of a discrete time sequence {1,0,2,3} is

The Fourier series of a real periodic function has only (P) cosine terms if it is even (Q) sine terms if it is even (R) cosine terms if it is odd (S) sine terms if it is odd Which of the above stateme

Given that F(s) is the one-side Laplace transform of , the Laplace transform of is