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Foundation6 past questions

Magnetic properties of materials

Learn about diamagnetic, paramagnetic, and ferromagnetic materials, their magnetic susceptibility, temperature dependence, Curie temperature, and the role of domains.

Why this shows up in the exam

NEET tests your understanding of how different materials respond to magnetic fields and the underlying reasons for their behavior.

How NEET tests this

Direct recall · 3 QsMatch the columnsStatement combination

Learn the idea

Magnetic susceptibility χ tells the direction and strength of a material’s response to an external field; its sign (negative or positive) decides whether the material is repelled or attracted, and its magnitude distinguishes diamagnetic, paramagnetic and ferromagnetic behaviour.

🧠 Memory hook: D‑P‑F: D is Down (negative, repels), P is Positive tiny (weakly attracts), F is Fierce (big positive, strongly attracts) – like a traffic light: red, amber, green.

Get this one clearly and it pays off every single time it shows up in the paper. 🎯

Formulas & facts to keep ready

  • Magnetic susceptibility χ = M/H (magnetisation per unit field) as defined in NCERT
  • Diamagnetic: χ < 0, very small (≈ -10⁻⁵), temperature independent, repelled by both poles
  • Paramagnetic: χ > 0, small (≈10⁻⁵–10⁻³), follows Curie's law χ = C/T, attraction weakens with temperature
  • Ferromagnetic: χ ≫ 0, shows spontaneous magnetisation and domains; above Curie temperature Tc it becomes paramagnetic
  • Curie temperature Tc is the temperature above which a ferromagnet loses its permanent magnetisation and obeys Curie's law
  • Magnetic domains are microscopic regions of uniform magnetisation; external field aligns domains leading to saturation

How to approach it

  1. 1Read the question and note which property (sign of χ, temperature effect, domain behaviour) is being queried
  2. 2Recall the χ sign and magnitude for diamagnetic, paramagnetic and ferromagnetic materials
  3. 3Apply the appropriate rule: negative χ → repulsion from any pole; positive small χ → weak attraction and varies as 1/T; large positive χ → strong attraction and domain alignment
  4. 4If temperature is involved, check whether the material is above or below its Curie temperature to decide if it behaves ferromagnetically or paramagnetically

Worked example — watch it click

If a diamagnetic substance is brought near the north or the south pole of a bar magnet, it is:

  • A)repelled by the north pole and attracted by the south pole
  • B)attracted by the north pole and repelled by the south pole
  • C)attracted by both the poles
  • ✅repelled by both the poles

The concept behind this problem

The worked example asks what a diamagnetic substance does near a magnet; it tests the key idea that diamagnets have negative susceptibility and are therefore repelled by both north and south poles.

Step by step

  1. 1Diamagnetic substances have negative susceptibility and are repelled by magnetic fields.
  2. 2When brought near either pole of a magnet, they experience a repulsive force because they develop an induced magnetic moment opposite to the applied field direction.
  3. 3Therefore, they are repelled by both north and south poles.

Watch out

Students often think opposite poles attract and same poles repel

Common slip-ups that cost marks

  • •Mixing up attraction/repulsion for diamagnetic and paramagnetic substances
  • •Assuming all magnetic materials have positive χ and forgetting the negative χ case
  • •Overlooking the Curie temperature and treating ferromagnets as magnetic at any temperature

🌟 That's the whole idea — you've got this. Try the practice set below; every question you attempt makes it stick a little harder.

Practise it

These are real questions from past NEET papers that test this exact idea.

Question 1 of 6NEET 2009

If a diamagnetic substance is brought near the north or the south pole of a bar magnet, it is:

Push further

More challenging

14 harder questions built from the past papers above — a step up in difficulty, with distractors designed so you can't get there by elimination. Written and checked by our reviewers, not from a real paper.

Question 1 of 14

A material used for temporary magnets, such as in a relay switch, should ideally possess which combination of magnetic properties?

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