SS 03 : questions

Q1.  The discrete-time signal x (n) = (-1)^n is periodic with fundamental period ?

Q2. The Fourier transform (FT) of a function x (t) is X (f). The FT of dx(t )/ dt will be.

Q3. Inverse Fourier transform of u(w) is

Q4. If G(f) represents the Fourier Transform of a signal g (t) which is real and odd symmetric in time, then G (f) is

            (A) complex. 

            (B) imaginary.

            (C) real. 

            (D) real and non-negative.

Q5.  The spectrum of x (n) extends from − wo to + wo , while that of h(n) extends from − 2w o to + 2 wo. 

        The spectrum of y(n) =  h(n) *x(n)  extends  from

        (A) − 4 wo to + 4w o

        (B)  − 3wo to + 3wo

        (C) − 2 wo  to + 2wo

        (D)  − wo  to + wo

Q6. The signals x1(t ) and x2 (t) are both bandlimited to (− w1,  +w1  )   and (− w2,  +w2)   respectively. 

        The Nyquist sampling rate for the signal   x1(t) x2(t)will be

         (A) 2w1 if w1 > w2;  (B)  2w2 if w1 < w2  ; (C)  2(w1 + w2)  ;  (D)  (w1 + w2)/2

Signals and Systems : Short Answer Questions

Day 1 :

SS:U1:
Q1. Is the signal
 x(t) = 2sin(2/3)t + 3cos(2π/5)t periodic ? If so, what is it's period.
Q2. Sketch the even and odd components of x(t) = e^-tu(t)
Q3. Is x(t) = cos2πfot a power signal ?
Q4. If x(t) = A for 0<t<T. Plot x(2t) and x(t/2). What is this operation called.
Q5. What do you understand by the term BIBO stability ? Explain mathematically.
Q6. Write the mathematical formulae for finding the : Fourier transform, Laplace transform for a given function f(t). What is w and s ? How are they related ?
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