A fresh set of 20 random questions is generated every time you open this page and every time you refresh it.For each of the following multiple choice questions, choose the most appropriate answer :
1. Two rectangular waveforms of duration t1 and t2 seconds are convolved. What is the shape of the resulting waveform?
2. A system is said to be defined as non causal, when
A. The output at the present depends on the input at the current time
B. The output at the present depends on the input at a time instant in the future
C. The output at the present depends on the input at an earlier time
D. The output at the present does not depend on the factor of time at all
3. A system which is linear is said to obey the rules of
D. Both scaling and additivity
4. Which of the following is/are not a property/properties power spectral density function Sx(?)?
A. Sx(?) is a even function of ?
B. Sx(?) is real function of ?
C. Sx(?) is a odd function of ?
D. Sx(?) is non-positive function of ?Sx(?) ? 0 for all ?
5. Which result is generated/ obtained by the addition of a step to a ramp function ?
A. Step function of zero slope
B. Ramp Function shifted by an amount equal to step
C. Ramp function of zero slope
D. Step Function shifted by an amount equal to ramp
6. In a complex wave, the negative half of the wave is a reproduction of the positive half wave. Then
A. The wave does not contain triple harmonics
B. The wave does not contain even harmonics
C. The wave does not contain odd harmonics
D. The wave contains only fundamental and third harmonic
7. Under which conditions does an initially relaxed system become unstable ?
A. Only if unbounded input generates bounded output
B. Only if bounded input generates unbounded output
C. Only if bounded input generates bounded output
D. Only if unbounded input generates unbounded output
8. According to Rayleigh’s theorem, it becomes possible to determine the energy of a signal by________
A. Estimating the area under the square root of its amplitude spectrum
B. Estimating the area under the square of its amplitude spectrum
C. Estimating the area exactly half as that of its amplitude spectrum
D. Estimating the area under the one-fourth power of its amplitude spectrum
9. Baseband transmission of a digital signal is possible only if we have a ____ channel.
C. Low rate
D. High rate
10. What does the spectral density function of any signal specify?
A. Generation of energy or power
B. Distribution of energy or power
C. Conservation of energy or power
D. Consumption of energy or power
11. With respect to time, ________is the rate of change
12. Damped sinusoids are _____
A. Sinusoid signals multiplied by decaying exponentials
B. Sinusoid signals divided by growing exponentials
C. Sinusoid signals divided by decaying exponentials
D. Sinusoid signals multiplied by growing exponentials
13. What would happen if the value of term [(m-x) / (? ? 2)] increases in the expression of Guassian CDF?
A. Complementary error function also goes on increasing
B. Complementary error function goes on decreasing
C. Complementary error function remains constant or unchanged
D. Cannot predict
14. For Ergodic Process
A. Ensemble Average is not equal to time Average
B. Ensemble Average < Time Average
C. Ensemble Average > Time Average
D. Ensemble Average equal to time Average
15. FIR digital filter having __________ stability than FIR filter.
A. Good stability
B. Poor stability
C. Stability not guarnteed
D. Poor stability
16. The discrete time system describes by y(n) = x(n)is
A. Non-casual, non-linear, time variant
B. Non-casual, Linear, time invariant
C. Casual, Linear, time varying
D. Casual, non-linear, timevari
17. According to the time-shifting property of Laplace Transform, shifting the signal in time domain corresponds to the ______
A. Multiplication by est0 in the time domain
B. Multiplication by est0 in the frequency domain
C. Multiplication by e-st0 in the frequency domain
D. Multiplication by e-st0 in the time domain
18. Where does the maximum value of auto-correlation function of a power signal occur?
A. At origin
B. At extremities
C. At unity
D. At infinity
19. If f(t) is an even function, the coefficients Fn in the exponential form of Fourier series
A. Are real
B. Are imaginary
C. Are complex
D. May be real or imaginary
20. Auto correlation function
A. Is an even function of t
B. Is both an odd and even function of t
C. Is an odd function of t
D. May be an even or odd function of t
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