Solve the on-axis magnetic field of an air-core solenoid.
solenoidFieldSolve the on-axis magnetic field of an air-core solenoid.
The identical function behind the /lab/solenoid table. Returns the centre field per amp-turn and at the requested turns and current, the on-axis profile out to three half-lengths, the span over which the field holds to within 1% and 5% of its centre value, the field at the coil mouth as a fraction of the centre, how far the infinite-solenoid shortcut mu0nI overstates the answer, and the turn count below which the closed form should not be used on this geometry. Dimensions are in millimetres. The field is exactly linear in turns x current, so only that product changes the answer.
Every result carries provenance.canonicalUrl — the published page for these exact inputs, or the lane hub when they are off the published grid.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| turns | No | Number of turns. Defaults to 1, which is what the published pages state (their figures are per amp-turn). The field is exactly linear in turns x current. | |
| length | Yes | Winding length along the axis, in millimetres. | |
| current | No | Winding current in amperes. Defaults to 1. Only the product of turns and current changes the answer. | |
| diameter | Yes | Mean winding diameter in millimetres. |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
| inputs | Yes | The parsed inputs, echoed back with defaults filled in. | |
| result | Yes | The solved analysis. Shape is per-tool. | |
| license | Yes | ||
| provenance | Yes |