WorksheetsSS- Revision 3
Total questions: 30
Worksheet time: 15mins
Which of the following is a causal system?
y(t)=x(t2)
y(t)=x2(t)
y(t)=x(−t)
y(t)=x(2t)
Find the Fourier series representation of the signal is
x(t)=3cos2πt and determine the Fourier series coefficients.c0=1, c1=61, c−1=61
c1=61
c−1=61
c1=61, c−1=61
If a periodic signal has an even symmetry, then Fourier series contains
Only sine terms
Only cosine terms
Constant and cosine terms
Both sine and cosine terms
The value of
e∞ is------------------
(a)
The value of
e−∞ is------------------
(a)
Laplace Transform transforms a function from
f(t) to F(s)
F(s) to f(t)
f(t) to f′(t)
f"(t) to f′(t)
Which one is the correct definition of Laplace Transform?
F(s)=∫0∞e−stf(t)dt
F(s)=∫0tf(t)g(t−u)
What is the Laplace Transform for f(t)=t3 ?
s31
s32
s46
s33
What is Laplace Transform for e−2t ?
s−21
s+21
s2
s21
What is Laplace Transform for sin 2t ?
s2+22
s2+2s
s2+42
s2+4s
What is Laplace Transform for 6 sin 2t ?
s2+42
s2+4s
s2+46
s2+412
Define this property: L(f(t)eat)=F(s−a)
Linearity Property
First Shifting Property
Convolution Theorem
Second Shifting Property
L(e3tt) Based on first shifting property, what is a value?
1
2
3
4
Find L(e3tt)
(s2)1
(s−3)21
(s−2)21
(s)1
L(e2t sin t) What is a and f(t)?
a=2, f(t)=e2t
a=4, f(t)=cos t
a=2, f(t)=sin t
Find L(cos t)
s2+11
s2+41
s2+1s
Find L(e2tsin 2t)
(s−1)2+11
(s−2)2+4s
(s−4)2+1s
Find L(t3−3t2+5t)
s46−(s36)+s25
s33−(s(2)1)+s1
s32−(s(2)3)+s5
Find L(e3t(t3−3t2+5t))
(s−3)42−⎝⎛((s−3)3)3⎠⎞+(s−3)25
(s−3)46−((s−3)36)+(s−3)25
(s−3)32−((s−3)(2)3)+s−35
L(t cos 6t) Which Laplace property is use to solve this?
Linearity Property
Derivative of Laplace Transform
First Shifting Property
Second Shifting Property
L(t sin 4t) What is n, f(t) and F(s)?
n=1, f(t)=sin 4t, F(s)=s2+16s
n=4, f(t)=t, F(s)=s2+164
n=1, f(t)=cos 6t, F(s)=s2+14s
Find L(tsin 4t)
s2+42
−(s2+4)24s
−(s2+16)28s
L(sin2t) What is f(t), f′(t) and f(0) ?
f(t)=sin2t, f′(t)=2 cost, f(0)=0
f(t)=sin2t, f′(t)=sin 2t, f(0)=0
f(t)=cos2t, f′(t)=− sin2t, f(0)=1
Find the Fourier Transform of an Exponential signal
f(t)=e−atu(t),a>0a+jw1
a−jw1
−a+jw1
−a−jw1
Which of the following is the Analysis Equation of Fourier Transform?
F(w)=∫−∞∞f(t)ejwt dt
F(w)=∫0∞f(t)ejwtdt
F(w)=∫0∞f(t)e−jwtdt
F(w)=∫−∞∞f(t)e−jwtdt
The Fourier Transform of a function
X(t) is X(w). what will be the fourier transform of dtdX(t) ?jfX(f)
j2πfX(f)
dtdX(f)
jfX(f)
The Fourier Transform of a Gaussian Pulse is also a Gaussian pulse
True
False
Find the Inverse Fourier transform of δ(w)
2π1
2π
π1
π
Find the inverse Fourier Transform of f(t)=1
u(t)
δ(t)
e−t
jw1
f(x)=1, 0<x<∞ cannot be represented by a Fourier Integral
True
False
