Needles, Charts and Currents: teacher key

Magnets, grade 8 edition, written for 8th grade. How people learned to read Earth's magnetism, from south-pointing spoons to electric currents.

Read the book. Print this page for the key.

Questions and answers

In what direction did early Chinese compasses point?
- North
- East
- South (answer)
Who carried out the first magnetic declination survey?
- Edmond Halley (answer)
- Michael Faraday
- William Sturgeon
What happens to a compass at the magnetic poles?
- It spins north
- It does not show direction (answer)
- It points straight up
What are GPS receivers doing, as of November 2026?
- Taking the place of compasses (answer)
- Making magnets
- Blocking the solar wind
Why do scientists rely on indirect evidence about Earth's field?
- Direct observations go back just a few centuries (answer)
- Earth's field is too weak
- No one cares