GATE EC2003 question

Ans :
Number of Mesh = B - N + 1 where B = No of Branches
N = number of Nodes
Node equation = N - 1
where N = number of Nodes

here B = 7 , N = 4

so minium number of equation need to analyze the circuit is = N - 1 = 3

Qu(2):

The Laplace transform of of i(t) is given by
I(s) = 2 / s(1+s)
As t --> infinity, The value of i( t) tends to


Ans:
Inverse of I(s) ,
I(s) = 2/s -2/(1+s)
i(t) = 2 -2(e^-t) because L(1) = 1/s and L(e^-t .1) = 1/(S+1)
As t --> infinity ,
==> i(t) = 2 -2/(e^infinity)
==> i(t) = 2 - 2/infinity
== > i(t) = 2 because 2/infinity is zero

This is the answer I got. I am not sure about 2/infinity . ,,...

i don't know these answers are correct or not .. I didn't get key for GATE these question.

DIGITAL SIGNAL PROCESSING

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why derivatives ?

To find an approximation of one can do as follows.

1. Consider the function Hence, the problem is reduced to finding the value of f(25).
2. We have

   

3. According to linear approximation

   

4. The result, 2.926, lies fairly close to the actual value 2.924…

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