# Laplace transform

ranju

## Homework Statement

we have to solve the given circuit using laplace transform for i(t) for t>0 when switch k opened at t=0..
now all I wnated to make clear is the final circuit diagram of this in s-domain..[/B]

## The Attempt at a Solution

as I solved I considered the circuit to be in steady state before switch is opened so , current across inductor is 6A...[/B]

#### Attachments

• IMG_20141007_181238.jpg
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• IMG_20141007_181609.jpg
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Images are not clear.

What is i(0+) you are getting ?

ranju
well only the left hand portion is'nt clear.. in 1st pic.. there is 12V voltage source & in 2nd pic it is 12/s in s-domain..
i(0+)=i(0-) = 6A..

can you show your working for i(0-).

ranju
sorry actually I did a calculation mistake..i(0-) =4 A.. and I found the equivalent current of the circuit considering it in steady state before switch is opened.. so the inductor is dhorted so the whole 4 A current pass across the inductor branch..!

Are you sure the current will be 4 A,mine is coming 14 A.

ranju
you are right .. ..