Sunday, September 21, 2008

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.

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