Electronics (ECE) - MCQ Practice Questions

A continuous-time signal x(t) = 5cos(2πt + π/4) has a fundamental frequency of:

Which of the following is a causal system?

The Z-transform of x[n] = aⁿu[n] is:

Nyquist sampling rate for a signal with maximum frequency 5 kHz is:

The convolution of two sequences is commutative, meaning:

A system with H(z) = (z-0.5)/(z-0.8) has:

A continuous-time signal x(t) = e^(-2t)u(t) is applied to a system. What is the Laplace transform X(s)?

A discrete signal x[n] = {1, 2, 3, 2} has a length of 4 samples. What is the 4-point DFT at k=0?

A signal x(t) is time-limited to 0 to T seconds. What is the minimum sampling rate required to avoid aliasing if its bandwidth is B Hz?

A continuous-time signal x(t) = 5cos(2π×100t) is sampled at 250 Hz. What is the Nyquist frequency required?

For a causal LTI system with transfer function H(z) = 1/(1-0.5z^-1), the system is:

The energy of a discrete-time signal x[n] = (0.5)^n u[n] is:

Which of the following is a property of the Discrete-Time Fourier Transform (DTFT)?

A signal x[n] has Z-transform X(z) = 1 + 2z^-1 + 3z^-2 for |z| > 0. The signal values are:

The convolution of x[n] = {1, 2, 3} and h[n] = {1, 1} yields a sequence of length:

A signal has power spectral density S_x(f) that is nonzero only for |f| ≤ 2 kHz. The minimum sampling frequency is:

A finite-duration signal x[n] has length N=8. Its DFT X[k] has length:

The Z-transform of x[n] = n·(0.8)^n u[n] is:

A signal x(t) = sin(2πf₀t) is sampled at fs = 5f₀. What is the Nyquist sampling rate required?

The energy of signal x[n] = {1, 2, 1, -1} over the given support is: