ELECTRICITY & MAGNETISM · LAB 28

Magnetic-field simulator

Build arrangements of magnets and current-carrying conductors, then reveal the direction and strength of their combined magnetic field.

ACTIVE TOOLSELECT / MOVE

TOOLS

Select a source to drag it. Use the rotation control to turn magnets, coils and solenoids.

North / current outSouth / current inMagnetic fieldCompass north

FIELD MAGNITUDE—

move the probe

FIELD DIRECTION—

counter-clockwise from +x

NEAREST SOURCE—

distance —

DOMINANT EFFECTDIPOLE

no conductor selected

CONFIGURATIONSINGLE MAGNET

1 source

WHAT TO NOTICE

Magnetic fields form loops

Outside a magnet, field lines point from north to south; inside they return to complete closed loops. Around a wire, the right-hand grip rule gives the circular direction. Fields from every source combine by vector addition.

B = μ₀I / 2πrB_coil = μ₀NI / 2RB_total = ΣB_i

Educational two-dimensional approximation. Sources are softened near their centres and visual field-line density is illustrative.