[Jprogramming] Basic Question about the J Circuit Analysis Lab

[Ed Keith]

I suspect that "if the voltage reference is changed, the current is unaffected" means that if you change the arbitrary value assigned to ground (usually set to 0 Volts) it will not affect the curent. 

  -EdK
 
Ed Keith
e_d_k at yahoo.com


Blog: edkeith.blogspot.com


________________________________
From: Binayak Banerjee <binayak.banerjee at gmail.com>
To: programming at jsoftware.com
Sent: Tuesday, October 4, 2011 1:38 PM
Subject: [Jprogramming] Basic Question about the J Circuit Analysis Lab

Hi,

I started looking at the Circuit Analysis lab that was included in the J
Software release.  However, I'm having a problem understanding the basic
axioms underlying the treatment..

1. The first axiom is that the algebraic sum of the currents flowing into
and out of a "terminal" is 0.  I take this as Kirchoff's current law, and
have no issue with this.

2. The second axiom states that if the voltage reference is changed, the
current is unaffected.  <-- This I don't follow.

The lab later states that "voltage vectors which differ by a scalar map to
the same current".  Again, I'm not sure I follow.

Given a simple circuit consisting of a resistor, I get (from Ohm's law):

V = IR. or when V is a function of I, V = f(I).

Now, if I replace the (say) 10ohm reistor with a 5 ohm one, the same current
maps to twice the voltage.

Any clarification would be greatly appreciated.  I tried sending mail
directly to the author of the lab, but the mail bounced.

Regards,

Binayak
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