1
GATE ECE 2014 Set 1
MCQ (Single Correct Answer)
+2
-0.6
For a function g(t), it is given that $$\int_{ - \infty }^\infty {g(t){e^{ - j\omega t}}dt = \omega {e^{ - 2{\omega ^2}}}} $$ for any real value $$\omega $$. If y(t)=$$\int_{ - \infty }^t {g(\tau )d\tau ,\,then\,\int_{ - \infty }^\infty {y(t)\,dt} \,} $$ is
A
0
B
- j
C
$$ - {j \over 2}$$
D
$${j \over 2}$$
2
GATE ECE 2014 Set 1
Numerical
+1
-0
Consider two real valued signals, $$x\left( t \right)$$ band - limited to $$\,\left[ { - 500Hz,\,\,500Hz} \right]$$ and $$y\left( t \right)$$ band - limited to $$\,\left[ { - 1\,\,kHz,\,\,1kHz} \right].$$ For $$z\left( t \right)\,\, = \,x\left( t \right).y\left( t \right),$$ the Nyquist sampling frequency $$\left( {in\,\,kHz} \right)$$ is________.
Your input ____
3
GATE ECE 2014 Set 1
MCQ (Single Correct Answer)
+1
-0.3
A discrete - time signal x[n] = $${\rm{sin(}}\,{\pi ^2}n)$$, n being an integer is
A
periodic with period $$\pi$$
B
periodic with period $$\,{\pi ^2}$$
C
periodic with period is $$\pi /2$$
D
not periodic.
4
GATE ECE 2014 Set 1
MCQ (Single Correct Answer)
+2
-0.6
A system is described by the following differential equation, where u(t) is the input to the system and y(t) is output of the system $$\mathop y\limits^ \bullet \left( t \right) + 5y\left( t \right) = u\left( t \right)$$

When y(0) = 1 and u(t) is a unit step function, y(t) is

A
0.2+0.8e-5t
B
0.2-0.2e-5t
C
0.8+0.2e-5t
D
0.8-0.8e-5t