Explore topic-wise MCQs in Signals Systems.

This section includes 6 Mcqs, each offering curated multiple-choice questions to sharpen your Signals Systems knowledge and support exam preparation. Choose a topic below to get started.

1.

A certain square wave has a period of 4 msec. Its fundamental frequency will be

A. 0 Hz
B. 230 Hz
C. 250 Hz
D. 430 Hz
Answer» D. 430 Hz
Discussion
2.

Let Y(k) be the 5-point DFT of the sequence y(n) = {1 2 3 4 5}. What is the 5-point DFT of the sequence Y(k)?

A. [15 -2.5 + 3.4j -2.5 + 0.81j -2.5 - 0.81j -2.5 - 3.4j]
B. [1 5 4 3 2]
C. [5 25 20 15 10]
D. [5 4 3 2 1]
Answer» B. [1 5 4 3 2]
Discussion
3.

Inverse discrete Fourier transform of Y(k) = {1, 0, 1, 0} is

A. y(n) = {0, 0.5, 0, 0.5}
B. y(n) = {0.5, 0, 0.5, 0}
C. y(n) = {0.5, 0.5, 0, 0}
D. y(n) = {0, 0, 0.5, 0.5}
Answer» C. y(n) = {0.5, 0.5, 0, 0}
Discussion
4.

A finite duration discrete-time signal x[n] is obtained by sampling the continuous-time signal x(t) = cos (200πt) at sampling instants t = n/400, n = 0, 1, …, 7. The 8-point discrete Fourier transform (DFT) of x[n] is defined as:\(X\left[ k \right] = \mathop \sum \limits_{n = 0}^7 x\left[ n \right]{e^{ - j\frac{{\pi kn}}{4}}},\;k = 0,\;1,\; \ldots ,\;7.\)Which one of the following statements is TRUE?

A. All X[k] are non-zero
B. Only X[4] is non-zero
C. Only X[2] and X[6] are non-zero
D. Only X[3] and X[5] are non-zero
Answer» D. Only X[3] and X[5] are non-zero
Discussion
5.

In a discrete-time Low pass Filter, the frequency response is

A. Aperiodic
B. Aperiodic with response restricted to (-ω0 + ω0)
C. Periodic with period 2π
D. Quasi-periodic with response extending to infinity
Answer» D. Quasi-periodic with response extending to infinity
Discussion
6.

For the sequence x[n] = {1, -1, 1, -1}, with n = 0, 1, 2, 3, the DFT is computed as \(X\left( k \right) = \mathop \sum \limits_{n = 0}^3 x\left[ n \right]{e^{ - j\frac{{2\pi }}{4}nk}}\), for k = 0, 1, 2, 3. The value of k for which X(k) is not zero is

A. 0
B. 1
C. 2
D. 3
Answer» D. 3
Discussion