Electric and magnetic fields – basic principles
How it works
Electric fields arise from electric charges and exert forces on other charged bodies. The field lines run from positive to negative charges. Magnetic fields arise from moving charges, current-carrying conductors or permanent magnets. Magnetic field lines form closed loops; outside a bar magnet they run from the North pole to the South pole. Electric and magnetic phenomena are connected, for example in electromagnetism. Field strength describes how strongly a field acts at a location. Field line diagrams help to represent the direction and strength of a field clearly. In electric fields, forces act on charged particles; in magnetic fields, on moving charges as well as on magnets and magnetic materials.
Electric fields arise from charges and act on charged bodies. Magnetic fields arise from moving charges, electric currents or magnets; they act on moving charges as well as on magnets. Field lines show the direction of the field, and their density indicates where the field is stronger.
An example
What direction do the field lines of an electric field have between a positive and a negative point charge?
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50 Exercises
To the learning unit →Own explanation and own practice exercises by AmyMath. Subject reference framework: Physics. The topic assignment may vary by federal state.