Magnetisation: Diamagnetism, Paramagnetism and Ferromagnetism · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Oppose weakly, align weakly, lock strongly

Science · Electricity & Magnetism · ages 20-21
Name ______________________   Date ____________

  1. What happens to paramagnetic attraction as temperature rises?

    • It fades as heat jostles the alignment
    • It grows stronger with heat
    • It turns into permanent magnetism

  2. Which material has no permanent atomic moments and is gently repelled by a magnet?

    • A diamagnet
    • A paramagnet
    • A ferromagnet

  3. A copper core multiplies a solenoid field as strongly as an iron core.

    Circle one:   True   False

  4. Iron is heated above its Curie temperature. What happens to its magnetism?

    • It stays ferromagnetic but weaker
    • It loses order and turns paramagnetic
    • It becomes superconducting

  5. Why does an iron core multiply the field of a solenoid?

    • Iron conducts electricity better than copper wire
    • Its domains align with the coil and add their own field
    • Iron cools the coil so resistance drops

  6. When stroking a nail with a magnet, why lift the magnet at the end of each stroke?

    • To avoid dragging the domains back out of line
    • To cool the nail between strokes
    • To count the paper clips more easily

  7. A transformer core flips its field millions of times a day. Which loop shape wastes least?

    • A wide square loop
    • A tall thin spike
    • A narrow loop with small area

  8. What does the area inside a hysteresis loop measure?

    • Energy lost as heat each cycle
    • The strength of Earth field
    • The number of domains in the sample
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Answer key

For grown-ups. Fold this page away before handing over the rest.

Oppose weakly, align weakly, lock strongly W1-mt_1apyQ1_1gg-s1

  1. It fades as heat jostles the alignment · Thermal jiggling fights the partial lining up of moments.
  2. A diamagnet · With nothing to align, the field induces only a weak opposing response.
  3. False · Copper lacks cooperative domains, so it adds almost nothing.
  4. It loses order and turns paramagnetic · Heat scrambles the locked domains, ending the strong response.
  5. Its domains align with the coil and add their own field · Aligned domains stack their field on top of the coil field.
  6. To avoid dragging the domains back out of line · The return stroke would undo the alignment just built.
  7. A narrow loop with small area · Small area means little heat lost on every flip.
  8. Energy lost as heat each cycle · Each trip around the loop dumps that much energy as heat.
Worksheet · LightMySky