Question 297Electricity & Electronics - QMED

You are correct, the answer is A) heat generated by magnetic polarity reversals. Hysteresis is a phenomenon that occurs in magnetic materials, such as those used in electrical generators and transformers. When the magnetic field in the material is reversed, energy is lost due to the realignment of the magnetic domains within the material. This energy loss manifests as heat, which is the cause of the power loss associated with hysteresis. The other answer choices are incorrect because they do not directly relate to the phenomenon of hysteresis. Arcing at the brushes, excessive field current, and pulsating terminal current can all contribute to power losses in electrical equipment, but they are not the specific cause of hysteresis.