Signals and Systems - Online Test
Q1. Let f(x) be a real, periodic function satisfying f(−x) = −f(x). The general form of its Fourier series representation would be
Answer : Option B
Explaination / Solution:
Q2. A series RL circuit is excited at t = 0 by closing a switch as shown in the figure.
Assuming zero initial conditions, the value of 
is
is
Answer : Option D
Explaination / Solution:
Q3. Consider a linear time invariant system x = Ax, with initial condition x(0) at t = 0. Suppose α and β are eigenvectors of (2 x 2) matrix A corresponding to distinct eigenvalues λ1 and λ2 respectively.
Then the response x(t) of the system due to initial condition x(0) = α is
Answer : Option A
Explaination / Solution:
Q4. In the given network V1 = 100∠0° V, V2 = 100∠ − 120° V, V3 = 100∠ + 120° V. The phasor
current 𝑖 (in Ampere) is
Answer : Option D
Explaination / Solution:
Q5. In the given network V1 = 100∠0°V, V2 = 100∠-120°V, V3 = 100∠+120°V. The phasor
current i (in Ampere) is
Answer : Option A
Explaination / Solution:
Q6. Let z(t) = x(t) * y(t), where "*" denotes convolution. Let C be a positive real-valued constant. Choose the correct expression for z (ct).
Answer : Option A
Explaination / Solution:
Q7. A three-winding transformer is connected to an AC voltage source as shown in the figure.
The number of turns are as follows: N1 = 100, N2 = 50. If the magnetizing current is
neglected, and the currents in two windings are 
and 
then
what is the value of the current 
in Ampere?
and then
what is the value of the current in Ampere?
Answer : Option A
Explaination / Solution:
Q8. Consider the system with following input-output relation
where, x[n] is the input and y[n] is the output. The system is
where, x[n] is the input and y[n] is the output. The system is
Answer : Option D
Explaination / Solution:
Q9. RA and RB are the input resistances of circuits as shown below. The circuits extend infinitely in the
direction shown. Which one of the following statements is TRUE?
Answer : Option D
Explaination / Solution:
Q10. 
Let a causal LTI system be characterized by the following differential equation, with initial rest condition
Where x(t) and y(t) are the input and output respectively. The impulse response of the system is (u(t) is the unit step function)
Answer : Option B
Explaination / Solution:
