# Is the following Wikipedia statement true?

Only nine types of element (memristor not included), five passive and four active, are required to model any electrical component or circuit

From the Wikipedia "Electrical Element" article.

Is this statement correct?

• Are you planning to change the citation needed into a link to this website? – Huisman Oct 26 '19 at 15:02
• The statement is out of the context. This is about linear and one-port elements – Huisman Oct 26 '19 at 15:10
• @Huisman I just want to know if the statement is correct. – dilinex Oct 26 '19 at 15:17
• Without context it is by definition incorrect :) – Huisman Oct 26 '19 at 15:20

As @Huisman points out, this statement applies only to linear ideal elements. Specifically, the statement does not apply to non-linear elements or, in general, to real elements. The structure of the article suggests this distinction but the single sentence, taken out of context, can be a bit misleading.

Having made that qualification, I think the statement is correct. The only way to prove that it is not correct is to produce a counter example and I can't think of one.

• Does this apply to n-port elements? – dilinex Oct 26 '19 at 15:25
• I think the statement is correct. Citation needed I guess? I really wonder why this answer is accepted... – Huisman Oct 26 '19 at 15:32
• If you think it's true and haven't yet disproven it, it's a conjecture, not proven correct. – IceGlasses Oct 26 '19 at 19:31
• @IceGlasses I agree. I wanted to clarify the issue and point out the logical problem, that it's very difficult to prove that there is no element that can be modeled by the listed nine ideal elements. The question itself is poorly posed. I tried to be honest about what I believed as opposed to what I knew. – Elliot Alderson Oct 26 '19 at 19:45
• @Huisman Yes, I agree with your discomfort. It seems to me that the whole premise of accepting answers and voting on answers is flawed, because it depends on the opinions of relatively inexperienced readers. We've all seen truly crap answers voted up and accepted because the OP didn't know any better or pulled the trigger too quickly. Sometimes I am weary and just play the game. Sorry. – Elliot Alderson Oct 26 '19 at 22:18

"Any electrical component or circuit" is far too broad.

The elements being discussed only apply to lumped-circuit models, in which the connections between elements are assumed to be ideal — no resistance, no electromagnetic field (parasitic) effects, no delays, etc.

Such models are by definition only an approximation to real-world circuits to begin with.

• The statement is you can model any electrical component or circuit. Your answer is models are by definition only an approximation to real-world circuits to begin with. Is this because the modelling fails to meet the reality or because there are more than 9 linear one-port elements? – Huisman Oct 26 '19 at 17:32
• @Huisman: Modeling fails, because not every electrical component or circuit can be adequately represented as a finite number of lumped elements. – Dave Tweed Oct 26 '19 at 17:38
• But isn't that exactly what the verb "model" means? A model tries to approach the reality, but will be definition always fail to be identical to reality. Only reality itself will succeed to be identical to reality. So, the statement is correct or incorrect? – Huisman Oct 26 '19 at 18:21