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. The _____ of a composite signal is the difference between the highest and the lowest frequencies contained in that signal
A. frequency
B. period
C. bandwidth
D. amplitude
2. Auto correlation function
A. is an even function of t
B. is an odd function of t
C. may be an even or odd function of t
D. is both an odd and even function of t
3. 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
4. For a second order system, damping ratio ? is such that 0 < ? <. Then the roots of characteristic equation are
A. real but not equal
B. imaginary
C. complex conjugate
D. real and equal
5. Two rectangular waveforms of duration t1 and t2 seconds are convolved. What is the shape of the resulting waveform?
A. Triangular
B. Trapezoidal
C. Rectangular
D. Semi-circular
6. Generally, the convolution process associated with the Laplace Transform in time domain results into________
A. Simple multiplication in complex frequency domain
B. Simple division in complex frequency domain
C. Simple multiplication in complex time domain
D. Simple division in complex time domain
7. Which result is generated/ obtained by the addition of a step to a ramp function ?
A. Step function of zero slope
B. Ramp function of zero slope
C. Ramp Function shifted by an amount equal to step
D. Step Function shifted by an amount equal to ramp
8. The inverse Laplace transform of 1/(s a)2 is
A. eat
B. t eat
C. t2 eat
D. eat/t
9. Under which conditions does an initially relaxed system become unstable ?
A. only if bounded input generates unbounded output
B. only if bounded input generates bounded output
C. only if unbounded input generates unbounded output
D. only if unbounded input generates bounded output
10. The Fourier series of an odd periodic function contains
A. odd harmonics only
B. even harmonics only
C. cosine harmonics only
D. sine harmonics only
11. What is the value of an area under the conditional PDF ?
A. Greater than 0 but less than 1
B. Greater than 1
C. Equal to 1
D. Infinite
12. A time invariant system is a system whose output
A. vanishes with a delay in input
B. remains same with a delay in input
C. decreases with a delay in input
D. increases with a delay in input
13. A system which is linear is said to obey the rules of
A. homogeneity
B. scaling
C. additivity
D. both scaling and additivity
14. Double integration of a unit step function would lead to
A. an impulse
B. a parabola
C. a ramp
D. a doublet
15. 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
16. Baseband transmission of a digital signal is possible only if we have a ____ channel.
A. low-pass
B. bandpass
C. low rate
D. high rate
17. Which property of fourier transform gives rise to an additional phase shift of -2? ftd for the generated time delay in the communication system without affecting an amplitude spectrum ?
A. Time Scaling
B. Linearity
C. Time Shifting
D. Duality
18. Where is the ROC defined or specified for the signals containing causal as well as anti-causal terms?
A. Greater than the largest pole
B. Less than the smallest pole
C. Between two poles
D. Cannot be defined
19. Which one of the following is correct? Energy of a power signal is
A. finite
B. zero
C. infinite
D. Zero to Infinity
20. In RLC circuits the state variables generally selected are
A. voltages across capacitors
B. currents through resistances and voltages across capacitors
C. currents through resistances and capacitances
D. currents through inductances and voltages across capacitances
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