List of top Electronics and Communication Engineering Questions

In a photodiode, light produces
LEDs are based on the principle of
The SiO\(_2\) is grown by exposing the epitaxial layer to an oxygen atmosphere while being heated to about 1000\(^\circ\)C, because Silicon dioxide has the fundamental property of
The rise time of a BJT is 3.5 micro seconds. Find its transition frequency.
An 'n' channel JFET has \(I_{DSS}=8\text{mA}\), \(V_P=-5\text{V}\). Determine the minimum value of \(V_{DS}\) for \(V_{GS}=-2\text{V}\) in the pinch off region.
Choose the wrong one with respect to nMOSFET compared to pMOSFET
Which of the following is not correct, when the collector base junction is reverse biased?
The electrical conductivity of pure semiconductor can be increased by
Phase variation with respect to frequency is given by \( \phi(\omega) = 2\omega^2 + \cos\omega \). Then, group delay of the system is
The LTI system is said to be initially relaxed system when
The frequency response of LTI system is given by the Fourier Transform of the ____ of the system.
Unilateral Z transform of x(n) is equivalent to bilateral Z-transform of
Match the following with respect to region of convergence
\( x(n) \) ROC
AInfinite duration causal sequenceIEntire z-plane except at \( z = 0 \)
BFinite duration causal sequenceIIEntire z-plane except at \( z = \infty \)
CInfinite duration anticausal sequenceIII\( |z| > \alpha \), exterior of a circle of radius \( \alpha \)
DFinite duration anticausal sequenceIV\( |z| < \beta \), interior of a circle of radius \( \beta \)
Which of the following is not correct with respect to Z-transforms?
The condition for orthogonality of two functions \( x_1(t) \) and \( x_2(t) \) in terms of correlation is
Consider a causal LTI system with impulse response \( h(t) = e^{-bt}u(t) \). Find the output of the system for an input \( x(t) = 3e^{-at}u(t) \).
The Fourier transform of the following signal is \[ x(t) = \begin{cases} 1+\cos \pi t & |t|<1 \\ 0 & |t|>1 \end{cases} \]
Which of the following statement is not correct?
The amplitude and phase spectrum of exponential Fourier Series about vertical axis respectively, is
The exponential Fourier series coefficient \( C_{-n} \) in terms of trigonometric Fourier coefficients is
Which of the following system is non-causal sytem? (Typo: "sytem" should be "system")
Driving point impedance of the function \( F(s) = \frac{(s+k_1)(s+k_2)(s+k_3)}{(s+1)(s+2)(s+3)} \) is
When two, two-port networks are connected in series, then
A transfer function is given by \( H(s) = \frac{2(s+2)(s+4)}{(s+3)(s+5)(s+7)} \). Then the transfer function becomes zero when
For a series RLC circuit which of the following statement is not correct?