Magnets always carry two poles that attract or repel by one simple rule, and magnetism turns out to be inseparable from electricity, since a current creates a magnetic field and a changing magnetic field creates a current, the conceptual link the HESI A2 physics subtest tests directly.
ObjectiveP.5.3Read4 minExam weightElectricity and Magnetism ≈ 16% of Physics
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You can explain why every magnet has a north pole and a south pole, and predict whether two poles will attract or repel.
You can describe how an electric current creates a magnetic field around itself, including how a coil and an iron core turn that field into a switchable electromagnet.
You can describe how a changing magnetic field induces a current in a nearby conductor, and name the everyday devices, generators, transformers, and MRI machines, built on that link.
What the lesson concludes
Every magnet has a north pole and a south pole together; cutting a magnet in half never isolates a single pole, it only makes two smaller two-pole magnets.
Like poles repel and unlike poles attract, and the force acts along the line joining the two poles.
A moving electric charge, meaning any current, creates a magnetic field around itself, which is why a current-carrying wire deflects a nearby compass needle.
Wrapping a current-carrying wire into a coil around an iron core builds an electromagnet, whose pull grows with more turns or more current and switches off entirely once the current stops.
A changing magnetic field near a conductor induces a current in that conductor, the principle behind generators, transformers, and MRI machines.