Part 3

Running it, and reading the answer

One run returns every answer in the circuit. The names they come back under, what each one means, and the two spellings of any of them.

Last updated 2026-09-11

Paste the description, pick an analysis, press Run. There is nothing to select first: a run returns every answer in the circuit, not the one you asked about.

The divider of the last chapter, the 12 V source across 1 kΩ and 2 kΩ in series, described as before:

Circuit Description

e1,1,0,12
r1,1,2,1'k
r2,2,0,2'k

Set Analysis to DC — direct current and press Run Symbulator. It comes back as two node voltages and three answers per element; three of them:

voltage at node 2

\[v_{2} = 8\,\mathrm{V}\]

current through r1

\[i_{r1} = \dfrac{1}{250}\,\mathrm{A}\]

power consumed by r1

\[p_{r1} = \dfrac{2}{125}\,\mathrm{W}\]

Exact, because 12, 1'k and 2'k are exact. 1/250 A is 4 mA; see “Settings” for how to be shown the decimal instead.

The answer names

A node's voltage is v and the node's name. An element's answers are a letter and the element's name.

Name	Answer	Where
`v2`	voltage at node 2	every node
`ir1`	current through r1	every element
`vr1`	voltage drop across r1	every element
`pr1`	power consumed by r1	every element
`apr1`	real power consumed	AC
`sr1`	complex power consumed	AC
`zr1`	impedance seen	AC, FD
`rr1`	resistance seen	DC

Resistance seen and impedance seen are the element's own voltage over its own current — useful on a source, where it is the resistance the source is driving.

Every name has two spellings. ir1 and i_r1 are the same current, v2 and v_2 the same voltage, and capitals make no difference. Use whichever you like, anywhere a name is accepted. Underscores, and subscripts in your answers says why both exist.

Signs

Two sentences, and every sign in the book follows from them:

A current is positive flowing from the element's first node toward its second.
A voltage drop is the first node's potential minus the second's.

So e1,1,0,12 above reports ie1 = -1/250 A: current flows out of the source's first node into the circuit, which is negative by that rule. Power follows the same rule, so a source delivering power consumes a negative one — and because that is the number nobody wants, a source's card shows the power delivered instead, as -pe1, labelled so. The answer pe1 itself is unchanged: p is always power consumed, in Evaluate, in Solve and in every saved file, and the card merely shows its negative. In AC a source's card also carries the power factor of the power it delivers.

If a sign surprises you, read the element's node order before doubting the answer.

Asking about one thing

The whole answer set is the point, but three cards narrow it when you want that:

Evaluate takes an expression over the answers — vr1/ir1, or pr1+pr2 — and can carry Conditions.
Solve solves equations written over the answers.
In TR, the results can be limited before they are computed, which saves real time. Limiting the results to save time has it.