Magnetic Force on a Current-Carrying Wire Calculator
Enter the magnetic field strength, current, wire length, and angle to find the magnetic force acting on the wire.
What This Calculator Does
A current-carrying wire placed in a magnetic field experiences a mechanical force — the same principle behind electric motors and speakers. This calculator finds that force from the magnetic field strength, the current in the wire, the wire’s length within the field, and the angle between the wire and the field lines.
The Formula
The force on a straight current-carrying wire in a uniform magnetic field is F = B × I × L × sin(θ), where B is the magnetic field strength in tesla, I is the current in amps, L is the length of wire in the field in meters, and θ is the angle between the wire and the field direction. The force is greatest when the wire is perpendicular to the field (θ = 90°) and zero when the wire runs parallel to the field (θ = 0° or 180°).
- Direction: found separately using the right-hand rule, perpendicular to both the current and the field.
- Maximum force occurs at a 90° angle, shown as a reference value above.
This is the standard electromagnetics formula used for general physics education and design planning purposes.