21. Continuous Impulse signal is a power or energy signal?
A. Power signal
B. Energy signal
C. Both power and energy
D. Neither power nor energy signal
Answer: D
On calculating using the power and energy calculation formula we will arrive at it is neither power nor energy signal.
22. Discrete impulse signal is a power or energy signal?
A. Power signal
B. Energy signal
C. Both power and energy signal
D. Neither power nor energy signal
Answer: B
On calculating using the energy formula we will get the energy of this signal as 1 which is a finite value. Thus it is an energy signal.
23. A unit impulse function has?
A. Large amplitude
B. Zero pulse width
C. Unity weight
D. All of the mentioned
Answer: D
An impulse function has an infinite or large-amplitude, zero pulse width, and unity weight which is concentrated at zero.
24. Which of the following is a common independent variable for speech signal, EEG, and ECG?
A. Time
B. Spatial coordinates
C. Pressure
D. None of the mentioned
Answer: A
Speech, EEG, and ECG signals are examples of information-bearing signals that evolve as functions of a single independent variable, namely, time.
25. Which of the following conditions made digital signal processing more advantageous over analog signal processing?
A. Flexibility
B. Accuracy
C. Storage
D. All of the mentioned
Answer: D
A digital programmable system allows flexibility in reconfiguring the DSP operations by just changing the program, as the digital signal is in the form of 1 and 0’s it is more accurate and it can be stored in magnetic tapes.
26. Which property does y(t)=x(1-t) exhibit?
A. Time scaling
B. Time shifting
C. Reflecting
D. Time shifting and reflecting
Answer: D
First the signal x(t) is shifted by 1 to get x(1+t) and it is reflected to get x(1-t). So, it exhibits both time-shifting and reflecting properties.
27. If x(n)=(0,1,2,3,3,0,0,0) then x(2n) is?
A. (0,2,4,6,6,0,0,0)
B. (0,1,2,3,3,0,0,0)
C. (0,2,3,0,0,0,0,0)
D. None of the mentioned
Answer: C
If x(n)=(0,1,2,3,3,0,0,0) then x(2n) is
Substitute n=0,1,2… in x(2n) and obtain the values from the given x(n).
28. If x(n)=(0,0,1,2,3,4,0,0) then x(n-2) is?
A. (0,0,2,4,6,8,0,0)
B. (0,0,1,2,3,4,0,0)
C. (1,2,3,4,0,0,0,0)
D. (0,0,0,0,1,2,3,4)
Answer: D
If x(n)=(0,0,1,2,3,4,0,0) then x(n-2) is
The signal x(n) is shifted right by 2.
29. If x(n)=(0,0,1,1,1,1,1,0) then x(3n+1) is?
A. (0,1,0,0,0,0,0,0)
B. (0,0,1,1,1,1,0,0)
C. (1,1,0,0,0,0,0,0)
D. None of the mentioned
Answer: A
If x(n)=(0,0,1,1,1,1,1,0) then x(3n+1) is
First, shift the given signal left by 1 and then time scale the obtained signal by 3.
30. If a signal x(t) is processed through a system to obtain the signal (x(t)2), then the system is said to be ____________
A. Linear
B. Non-linear
C. Exponential
D. None of the mentioned
Answer: B
Let the input signal be ‘t’. Then the output signal after passing through the system is y=t2 which is the equation of a parabola. So, the system is non-linear.
