Point neutre entre deux fils parallèles
Two parallel current-carrying wires each produce their own circular field, and somewhere between them those fields can cancel exactly. This simulation lets you find that neutral point and see how it shifts when you change the currents.
Comment utiliser cette simulation
- Set the current in each wire independently
- Reverse either current direction
- Move a probe around to map the resultant field
Ce qu’il faut observer
- With equal currents in the same direction the neutral point sits exactly midway
- Making one current stronger pushes the neutral point towards the weaker wire
- Reversing one current moves the cancellation point outside the pair entirely
La physique derrière
Each wire contributes B = μ₀I/(2πr), and the resultant field is the vector sum. A neutral point occurs where the two contributions are equal in magnitude and opposite in direction. For currents in the same direction that point lies between the wires, positioned so that I₁/r₁ = I₂/r₂ — closer to the weaker current.