Electronics and Communication Engineering
GATE ECE format:mcq PYQs
Build your understanding with focused practice from past exam papers.
Questions 101–110 of 426. Imported answers require independent review unless marked reviewed.
Question 20
Open questionECMCQ1 markNeeds review
A white Gaussian noise
with zero mean and power spectral density
, when applied to a first-order RC low pass filter produces an output
. At a particular time
, the variance of the random variable
is ______.Your answerChoose one option.
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Open questionECMCQ1 markNeeds review
A causal and stable LTI system with impulse response
produces an output
for an input signal
. A signal
is applied to another causal and stable LTI system with impulse response
. The resulting output is ______.Your answerChoose one option.
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Open questionECMCQ1 markNeeds review
For non-degenerate doped n-type silicon, which one of the following plots represents the temperature (
) dependence of free electron concentration (
)?Your answerChoose one option.
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Open questionECMCQ1 markNeeds review
In the circuit shown, the
step-down transformer and the diodes are ideal. The diodes have no voltage drop in forward biased condition. If the input voltage (in Volts) is
and the average value of load voltage
(in Volts) is
, the value of
is ______.
Your answerChoose one option.
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You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 36
Open questionECMCQ2 marksNeeds review
Consider the Earth to be a perfect sphere of radius R. Then the surface area of the region, enclosed by the 60°N latitude circle, that contains the north pole in its interior is ______.
Your answerChoose one option.
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Open questionECMCQ2 marksNeeds review
Consider a unity negative feedback control system with forward path gain
as shown.
The impulse response of the closed-loop system decays faster than
if ______.Your answerChoose one option.
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Open questionECMCQ2 marksNeeds review
A satellite attitude control system, as shown below, has a plant with transfer function
cascaded with a compensator
, where
and
are positive real constants. 
In order for the closed-loop system to have poles at
, the value of
must be ______.Your answerChoose one option.
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Open questionECMCQ2 marksNeeds review
A uniform plane wave with electric field
V/m is traveling in the air (relative permittivity,
and relative permeability,
) in the
direction (
is a positive constant,
is the unit vector along the
axis). It is incident normally on an ideal electric conductor (conductivity,
) at
. The position of the first null of the total magnetic field in the air (measured from
, in metres) is ______.Your answerChoose one option.
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You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 40
Open questionECMCQ2 marksNeeds review
A 4-bit priority encoder has inputs
, and
in descending order of priority. The two-bit output
is generated as 00, 01, 10, and 11 corresponding to inputs
, and
, respectively. The Boolean expression of the output bit
is ______.Your answerChoose one option.
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You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 41
Open questionECMCQ2 marksNeeds review
The propagation delay of the
MUX shown in the circuit is 10 ns. Consider the propagation delay of the inverter as 0 ns. 
If
is set to 1 then the output
is ______.Your answerChoose one option.
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