Physics

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Magnetic Force on a Current-Carrying Wire Calculator.

Calculate magnetic force on a wire segment in a uniform field.

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01

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Force: 0.3 N

Force

0.000000N

Results update automatically as you type.

Use Cases

Physics homework and exam problems

Quickly verify calculations for textbook problems involving the force on a straight current-carrying wire in a uniform magnetic field.

Example: A 2 A wire of length 0.5 m in a 0.3 T field at 30° gives a force of 0.15 N.

Engineering design of electromagnetic systems

Estimate the force on wires in motors, actuators, or magnetic levitation setups to help with preliminary design and safety checks.

Example: Check the force on a 1 m bus bar carrying 100 A in a 0.5 T field at 90°.

Frequently Asked Questions

How is the magnetic force on a current-carrying wire calculated?
The force is calculated using F = BIL sin(θ), where B is the magnetic field in teslas, I is the current in amperes, L is the wire length in meters, and θ is the angle between the wire and the magnetic field in degrees. The calculator uses this formula to output the force in newtons.
What is the angle to field in this calculator?
The angle to field is the angle between the direction of the current (along the wire) and the direction of the magnetic field. It is entered in degrees. The force is maximum when the angle is 90°, and zero when the wire is parallel to the field (0° or 180°).
What units are used for the inputs and output?
Current is in amperes (A), wire length in meters (m), magnetic field in teslas (T), and angle in degrees (°). The resulting magnetic force is given in newtons (N).

Tips & Common Mistakes

Tips

  • Ensure the angle is measured between the wire direction and the magnetic field direction, not the perpendicular component.
  • Use consistent units: amperes, meters, teslas, and degrees. The calculator handles the conversion to newtons.
  • For maximum force, set the angle to 90°; for zero force, use 0° or 180°.
  • Remember that the force direction is perpendicular to both the wire and the field, but this calculator only gives magnitude.

Common Mistakes to Avoid

  • Using the angle between the wire and the normal to the field instead of the field itself.
  • Forgetting to convert the angle to radians if using a manual formula, but this calculator accepts degrees directly.
  • Entering the magnetic field in gauss instead of teslas; 1 T = 10,000 gauss.

Last updated: August 13, 2026