Resistor Circuit — current arrow size ∝ magnitude, node colour ∝ voltage, resistor glow ∝ power
This circuit builder solves five classic DC resistor networks — series, parallel, mixed, voltage divider and Wheatstone bridge — using Ohm's law and nodal analysis, then draws the result with current-arrow size scaled to magnitude, node colour scaled to voltage, and resistor glow scaled to power dissipation. Adjust battery voltage and each resistor's value to see instantly how current redistributes, which resistor gets hottest, and how a voltage divider's output tap or a bridge's balance point respond.
A schematic circuit diagram where current arrows point in the direction of flow and grow with current magnitude, resistor bodies glow brighter as they dissipate more power, and node dots are colour-coded from cool (low voltage) to warm (high voltage).
Pick a circuit preset (Series 3R, Parallel 3R, Mixed, Voltage Divider, Bridge Circuit), then adjust battery voltage and R1, R2, R3 to see total resistance, total current, total power, node A voltage and the current through R1 update live.
In a Wheatstone bridge, the classic instrument for precisely measuring an unknown resistance, the bridge is "balanced" — zero current flows through the middle detector arm — exactly when the ratios of resistors on each side match, regardless of the supply voltage.
In series, the same current flows through every resistor and total resistance simply adds (R1+R2+R3). In parallel, every resistor shares the same voltage but splits the current, and total resistance is found from 1/Rtotal = 1/R1+1/R2+1/R3 — always smaller than the smallest individual resistor.
Two resistors in series across a battery split the supply voltage proportionally to their resistance values: Vout = V·R2/(R1+R2). This simulation's "Voltage Divider" preset taps the output at the junction between R1 and R2, exactly as used in countless real sensor and reference circuits.
The glow intensity is scaled to power dissipation P = I²R, so a resistor carrying more current, or with a higher resistance value at the same current, dissipates more power as heat and appears brighter — this is a visual proxy for how hot a real resistor would actually get.
It's a circuit arranged in a diamond shape used to precisely measure an unknown resistance by comparing it against known resistors — the bridge reaches "balance" (zero voltage between the two midpoints) when the ratio of resistors on each side matches, letting you solve for the unknown value.
You resolve the circuit piece by piece: first combine any resistors that are purely in parallel or series with each other using the standard formulas, then treat that combination as a single equivalent resistor and continue simplifying until you reach one final total resistance value.