ECE :: Exam Questions Paper
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With a line charge along z-axis the field intensity is E =
; which of the following figure shows an exact field distribution? -
The logic function f(A, B, C) =
m(0, 2, 4, 5, 6) can be represented by : -
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In amplitude modulation, carrier signals A cos ωt has its amplitude A modulated in proportion with message bearing (low frequency) signal m(t). The magnitude of m(t) is chosen to be __________ .
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The logic realized by the circuit shown in figure below is
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An image uses 512 x 512 picture elements. Each of the picture elements can take any of the 8 distinguishable intensity levels. The maximum entropy in the above image will be
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A tachometer has a sensitivity of 4 V/1000 rpm. Express the gain constant of the tachometer in the units volts/(rad/sec).
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Consider the signal x(n) = 1 + sin
n + 3 cosn + cos 
. Then Fourier series coefficients are __________ . -
A certain system has transfer function
a is a parameter. Consider the standard negative unity feedback configuration as shown below.
Which of the following statements is true? -
If a signal f(t) has energy E, the energy of the signal f(2t) is equal to __________ .
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For a npn BJT transistor fβ is 1.64 x 108 Hz. Cμ = 10-14 F; Cp = 4 x 10-13 F and DC current gain is 90. Find fT and gm (fβ = cut off frequency, Cμ = capacitance, Cp = parasitic capacitance, gm = transconductance, fT = gain BW product)
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V/rad/sec
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j, 
= |
A.
The closed loop system in never stable for any value of a a
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B.
For some positive values of a, the closed loop system is stable, but not for all positive values
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C.
For all positive values of a, the closed loop system is stable
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D.
The closed loop system is stable for all values of a, both positive and negative
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Use Routh criteria
|f(t)|2 dt
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