Produced by moving charges; magnetic flux density is measured in tesla.
Moving charges and magnets create magnetic fields B (tesla). Force on a wire F=BIL sinθ; on a charge F=qv×B. Field of a long wire B=μ₀I/2πr; of a solenoid B=μ₀NI/l. Ferromagnetic cores concentrate flux.
A 10 A wire in 0.5 T field gives 5 N per metre.
Magnetic fields explain how motors, transformers and sensors work, and they set the direction of forces on current-carrying conductors.
Produced by moving charges; magnetic flux density is measured in tesla.
Magnetic fields explain how motors, transformers and sensors work, and they set the direction of forces on current-carrying conductors.
Moving charges, including current in wires and the spin of electrons in magnetic materials.
B is the magnetic flux density in the material, and H is the field produced by the currents. In free space they are proportional, but they differ inside magnetic materials.
Typical applications include calculating the field inside a solenoid for a magnetic actuator, predicting the force on a wire in a loudspeaker coil and designing a Hall-effect sensor to detect a magnet's position.
Study "Electric fields and Coulomb's law" first (topic 19 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Right-hand rule. Flux Φ=BA in webers. Magnetic circuits analogous to electric circuits.
A 10 A wire in 0.5 T field gives 5 N per metre.
The next topic is "Faraday's law", which builds directly on this one.
It is classed as Beginner in Electrical Engineering (topic 20 of 106). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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