Chapter 2: Introduction to Signals Quiz

The image shows a/an _______________ signal.

• Unit step

• Unit impulse

• Unit pulse

• Exponential

Continuous time signals are expressed using:

• round brackets enclosing the time variable 'n' or 'k'

• square brackets enclosing the time variable 'n' or 'k'

• round brackets enclosing the time variable 't' or 'τ'

• square brackets enclosing the time variable 't' or 'τ'

The following are approaches to carry out linear continuous time convolution except:

• Mathematical approach

• Graphical approach

• Convolution table approach

• Numerical evaluation approach

The signal shown is expressed as:

• u[t-1]

• δ[n-2]

• u(t-2)

• δ(n-1)

Which statement is correct?

• An energy signal will have infinite power content.

• A power signal will have zero energy content.

• A signal must be either energy or power signal.

• An energy signal will have zero power content.

The formulae shown above describes which operation?

• Linear convolution

• Discrete time convolution

• Convolution sum

• Approximation of signals using unit impulse train

Which of the following describes an even signal? Select all that apply.

• The left hand and right hand portions of the graph are mirror images about the y-axis.

• f(t) = f(-t)

• f(t) = -f(-t)

• The graph of the signal is antisymmetric with respect to the origin.

Arrange the following steps for graphical evaluation of linear convolution in the correct sequence:

I. Plot the two signals

II. Multiply and find the area under the signals

III. Flip one of the signals and shift by t units.

IV. Plot the convolution result as a function of t.

V. Repeat for different values of t.

• II, IV, V, I, III.

• I, III, II, V, IV.

• I, II, III, V, IV.

• I, III, V, III, IV.

Which signal below can be categorised as a stochastic signal?

• Sinusoidal signal

• Cosine signal

• Performance of a stock market on a particular day

• Unit step signal

 $\int_{-\infty}^{\infty}\left(t+3\right)^2\delta\left(-3t-6\right)dt$  

Evaluate the above impulse integral.

•  $\frac{125}{3}$  

•  $-\frac{1}{3}$  
  

•  $-\frac{125}{3}$  

•  $\frac{1}{3}$