**Signals & Systems Electronics Engineering MCQ Questions Answers ECE**

1) **If a function f(t) u(t) is shifted to right side by t0,then the function can be expressed as**

a) f(t – t0) u(t)

b) f(t) u(t – t0)

c) f(t – t0) u(t – t0)

d) f(t +t0) u(t + t0)

2) **Damped sinusoids are _____**

sinusoid signals multiplied by growing exponentials

b. sinusoid signals divided by growing exponentials

c. sinusoid signals multiplied by decaying exponentials

d. sinusoid signals divided by decaying exponentials

3) **The poles of a digital filter with linear phase response can lie**

a)only at z = 0

b) only on the unit circle

c)only inside the unit circle but not at z = 0

d) on the left side of Real (z) =0 line

4) **Which block of the discrete time systems requires memory in order to store the previous input?**

Adder

b. Signal Multiplier

c. Unit Delay

d. Unit Advance

5) **The covariance function of a band limited white noise is**

a) A Dirac delta function

b) An exponentially decreasing function

c) A sinc function

d) A sinc2 function

6) **What are the number of samples present in an impulse response called as?**

string

b. array

c. length

d. element

7) **Two rectangular waveforms of duration T1 and T2 seconds are convolved. What is the shape of the resulting waveform ?**

a) Triangular

b) Rectangular

c) Trapezoidal

d) Semi-circular

8) **A discrete LTI system is non-causal if its impulse response is**

a) anu(n -2)

b) an-2u(n)

c) an+2u(n)

d) anu(n +2)

9) **What is the number of roots of the polynomial F(z) = 4z3 – 8z2 –z + 2, lying outside the unit circle ?**

a) 0

b) 1

c) 2

d) 3

10) **What does the signalling rate in the digital communication system imply?**

Number of digital pulses transmitted per second

b. Number of digital pulses transmitted per minute

c. Number of digital pulses received per second

d. Number of digital pulses received per minute