The problem ask me to find the tension on a capacitor after a switch has been opened.(adsbygoogle = window.adsbygoogle || []).push({});

I have everything in terms of equations in s-domain and I'm sure they aren't wrong because I checked on the book. My unique problem is to understand a certain passage necessary to find the voltage knowing the current.

I found I(s) and I know v(0)/s of the capacitor. Then I just used this relation to find V(s) and compute its value in time: I(s)=C (sV(s)-v(0)). Here I solved for V(s) and I got the wrong answer. In fact, the book uses a different equation, actually just I sign changes, the following: V(s)= (1/sC) I(s) - v(0)/s. The first thing I thought was it was a Typing error, but checking other exercises showed it wasn't.

So, my question is: why do we use it?

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# Homework Help: Tension on a capacitor from Laplace domain to time domain.

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