The magnetic material produced from the chemical combination of metal oxides and has a very high resistance to electric current is called

Analyze the question: We need a magnetic material that is made by chemically combining metal oxides and that has very high electrical resistance.

Concept: Ferrites are ceramic-like compounds made from iron(III) oxide (Fe₂O₃) combined with oxides of other metals such as manganese, zinc, nickel, or barium. They are ferrimagnetic. Because they are oxide compounds, they are poor electrical conductors, which gives them very high resistivity.

Why this matters: The high resistivity means very small eddy currents are induced in them. That is why ferrites are used in:

• transformer cores for high-frequency use
• radio antennas (ferrite rods)
• computer memory cores
• magnetic tapes

Checking each option:

• A. Ferrite substance: It is made from metal oxides and has very high resistivity. This matches the description.
• B. Paramagnetic substance: These are weakly attracted by a magnetic field (e.g., aluminium, platinum). The term describes magnetic behaviour, not a metal-oxide compound with high resistance.
• C. Ferromagnetic substance: These are strongly magnetic metals such as iron, cobalt, and nickel. They are good conductors, so they do not match "high resistance."
• D. Diamagnetic substance: These are weakly repelled by a magnetic field (e.g., copper, bismuth, water). They do not match the description.

Answer: A (ferrite substance)

Exam tip: Remember "Ferrite = Ferric oxide + other metal oxides = High resistance." If you see "oxides" and "high resistance" together in a magnetism question, think ferrite.