BARC-2018 EC:Full Syllabus Mock 1 for ESE & GATE EC Exams

Question 1

A source has alphabets {a, b, c, d} with corresponding probabilities {0.15, 0.2, 0.3, 0.35}. The minimum required average code word length to represent this source for error free reconstruction is

Question 2

How many half adder circuits are required to implement the four boolean functions.
D= A⊕B⊕C, where ⊕ is XOR gate.
E= A’BC +AB’C
F= ABC’ + (A’ + B’) C
G= ABC

Question 3

A silicon abrupt junction in thermal equilibrium at T=300K is doped such that

in n-region and

in the p-region. Consider N_c =

and N_a =

What will be the impurity doping concentrations N_d and N_a in n and p-regions and the built-in potential barrier, V_bi in the p-n junction respectively?

Question 4

Let X be the random variable. Consider the following table with the probability distribution values of X.

Find the value of P(X<4).Round upto two decimal places).

Question 5

Consider the system shown below:

D is a delay block of 1 unit. What is the impulse response of the cascaded system?

Question 6

A unity feedback system has forward path transfer function is given by

The settling time for 5% tolerance band is _________ seconds.

Question 7

Consider the circuit shown in figure

The circuit 2 is equivalent of circuit 1, the

MOSFET of circuit 1 is replaced by its Thevenin’s equivalent in circuit and thus circuit 1 reduces to a common gate circuit. The value of

will be. (Assuming the trans conductance of the two MOSFET are

and

and the

be

and

respectively)

Question 8

Consider a lossless transmissions line which is connected as shown in the figure

The average power dissipated in 25

load is__________ Watts.

Question 9

A PCM multiplexer system using 128 level quntization of 4 signal band limited to 10 kHz, 15 kHz, 5 kHz and 10 kHz respectively. Assume that each signal is sampled at its Nyquist rate. The increase in bandwidth if 512 quantization levels are used is________kHz.

Question 10

Find Vc(t) at t=1, the switch was open till t=0. At t=0, the switch is closed, consider zero initial conditions,

Question 11

Consider an n⁺ polysilicon-silicon dioxide n-type silicon MOS capacitor. Let N_d = 10¹⁵ cm^-3, t_ox =

,

and

. What will be the flat-band voltage? If

Question 12

The transfer function of a PID controller is given by

as

tends to zero

Question 13

Consider the following program for INTEL 8085.

LXI H, 2500 H
MVI C, 04 H
MVI A, 00 H
LOOP INX H
ADD M
DCR C
JNZ LOOP
STA 2450 H
HLT
After execution of program the decimal equivalent of data present at 2450 H is ____________ .