online course - (Laplace Transform problem)

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notoriusjt2

Joined Feb 4, 2010
209
I am in an online course and the questions/examples from the book are quite terrible. I have read the entire chapter and this is the first question from my chapter quiz. Could someone please post the basic steps(not the answer) needed to solve this problem as I am honstley clueless. I will then use those steps to try to solve the problem. Thank You
 

dachikid

Joined Oct 19, 2007
16
You might want to start by determining the impedance of the circuit withn the time domain. From there it's just a hop-skip and a jump away to the Laplace transform.
 

t_n_k

Joined Mar 6, 2009
5,455
You might want to start by determining the impedance of the circuit withn the time domain. From there it's just a hop-skip and a jump away to the Laplace transform.
While it might be informative there's no need to do that.

This is the process I would adopt.

1. Convert all components to the 's' domain.
An Inductor L becomes Ls
A Capacitor C becomes 1/(Cs)
A Resistor R stays as R
2. Treat the circuit as if it is a series-parallel network and solve it using techniques you have applied to series-parallel resistive networks in the past.

So then, that part of the circuit comprising the (1/2)F (or 2/s) capacitor in parallel with the 1Ω resistor would become

(2/s)/(1+2/s) [Remember two resistors in parallel - R1*R2/(R1+R2)]

To this you would add the (4/3)H or (4s/3) inductor term.

So that entire branch is equal to [4s/3 + (2/s)/(1+2/s)]. That branch is in parallel with the lone (3/2)F or (2/3s) capacitor.

It's just more fiddly than manipulating purely resistive terms because the algebra is complicated by the terms in 's' - but it's still just a process of careful algebraic manipulation.

Have a go at doing the problem - even if you go wrong, someone can then help you.
 
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