Indian Institute of Technology Mumbai (IIT-M) 2009 Other Bachelor's Degree GATE (ECE) - Question Paper

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Q. No. one – 20 Carry 1 Mark every
1. The order of the differential formula
2 3
4 t
2
d y dy
y e
dt dt

 -
+   + =
 
is
(A) one (B) two (C) three (D) 4
2. The Fourier series of a real periodic function has only
P. Cosine terms if it is even
Q. Sine terms if it is even
R. Cosine terms if it is odd
S. Sine terms if it is odd
Which of the above statements are correct?
(A) P and S (B) P and R (C) Q and S (D) Q and R
3. A function is provided ( ) two f t = sin t + cos2t. Which of the subsequent is true?
(A) f has frequency components at 0 and 1/2p Hz
(B) f has frequency components at 0 and 1/p Hz
(C) f has frequency components at 1/2p and 1/p Hz
(D) f has frequency components at 0, 1/2p and 1/p Hz
4. A fully charged mobile phone with a 12V battery is good for a 10minute talktime.
presume that, during the talk-time, the battery delivers a constant current
of 2A and its voltage drops linearly from 12 V to 10V as shown in the figure. How
much energy does the battery deliver during this talk-time?
(A) 220J (B) 12kJ (C) 13.2kJ (D) 14.4kJ
5. In an n-type silicon crystal at room temperature, which of the subsequent can have
a concentration of 19 three four ×10 cm- ?
(A) Silicon atoms (B) Holes
(C) Dopant atoms (D) Valence electrons
6. The full form of the abbreviations TTL and CMOS in reference to logic families are
(A) Triple Transistor Logic and Chip Metal Oxide Semiconductor
(B) Tristate Transistor Logic and Chip Metal Oxide Semiconductor
10min
t
0
10V
12V
v (t)
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(C) Transistor Transistor Logic and Complementary Metal Oxide Semiconductor
(D) Tristate Transistor Logic and Complementary Metal Oxide Silicon
7. The ROC of Z-transform of the discrete time sequence
( ) ( ) ( )
n n
1 1
x n u n u n one is
3 2



=   -   - -
   
(A)
1 1
z
3 2
< < (B)
1
z
2
> (C)
1
z
3
< (D) two < z < 3

Earning:   Approval pending.