[amp_mcq option1=”$${1 \over 3} < \left| z \right| < {1 \over 2}$$" option2="$$\left| z \right| > {1 \over 2}$$” option3=”$$\left| z \right| < {1 \over 3}$$" option4="$$2 < \left| z \right| < 3$$" correct="option3"]
Signal processing
82. The Fourier series of a real periodic function has only P. Cosine terms if it is even Q. Sine terms if it is even R. Cosine terms if it is odd S. Sine terms if it is odd Which of the above statements are correct?
P and S
P and R
Q and S
Q and R
Answer is Wrong!
Answer is Right!
83. The region of convergence of z-transform of the sequence $${\left( {{5 \over 6}} \right)^n}u\left( n \right) – {\left( {{6 \over 5}} \right)^n}u\left( { – n – 1} \right)$$ must be
[amp_mcq option1=”$$\left| z \right| < {5 \over 6}$$" option2="$$\left| z \right| > {5 \over 6}$$” option3=”$${5 \over 6} < \left| z \right| < {6 \over 5}$$" option4="$${6 \over 5} < \left| z \right| < \infty $$" correct="option3"]
84. The impulse response of an LTI system can be obtained by
Differentiating the unit ramp response
Differentiating the unit step response
Integrating the unit ramp response
Integrating the unit step response
Answer is Wrong!
Answer is Right!
Detailed SolutionThe impulse response of an LTI system can be obtained by
85. If $$F\left( s \right) = L\left[ {f\left( t \right)} \right] = {{2\left( {s + 1} \right)} \over {{s^2} + 4s + 7}}$$ then the initial and final values of f(t) are respectively
0, 2
2, 0
$$0,{2 over 7}$$
$${2 over 7},0$$
Answer is Wrong!
Answer is Right!
86. The inverse Laplace transform of the function $${{s + 5} \over {\left( {s + 1} \right)\left( {s + 3} \right)}}$$ is
2e-t - e-3t
2e-t + e-3t
e-t - 2e-3t
e-t + 2e-3t
Answer is Wrong!
Answer is Right!
87. The impulse response and the excitation function of a linear time invariant causal system are shown in figure (a) and (b) respectively. The output of the system at t = 2 sec is equal to
0
$$rac{1}{2}$$
$$rac{3}{2}$$
1
Answer is Wrong!
Answer is Right!
88. The z-transform of a signal is given by $$C\left( z \right) = {1 \over 4}{{{z^{ – 1}}\left( {1 – {z^{ – 4}}} \right)} \over {{{\left( {1 – {z^{ – 1}}} \right)}^2}}}.$$ Its final value is
$${1 over 4}$$
Zero
1
Infinity
Answer is Wrong!
Answer is Right!
89. The region of convergence of the z-transform of a unit step function is
[amp_mcq option1=”|z| > 1″ option2=”|z| < 1" option3="(Real part of z) > 0″ option4=”(Real part of z) < 0" correct="option2"]
Detailed SolutionThe region of convergence of the z-transform of a unit step function is
90. Increased pulse-width in the flat-top sampling, leads to
Attenuation of high frequencies in reproduction
Attenuation of low frequencies in reproduction
Greater aliasing errors in reproduction
No harmful effects in reproduction
Answer is Wrong!
Answer is Right!
Detailed SolutionIncreased pulse-width in the flat-top sampling, leads to