The Earth's Magnetic Field Flashcards

All 4 cards in this deck

What are the steps to show that the Earth has a magnetic field?
e.g. using a plotting compass on a bench with no magnets nearby

1. Use a compass, away from any magnets.
2. It always points in the same direction — north.
3. So the Earth must have a magnetic field.

What does the behaviour of a magnetic compass tell us about the core of the Earth?

The core must be magnetic — the Earth has a magnetic field with a north and a south pole.

Apart from a compass, what could be used to show that the Earth has a magnetic field?

A suspended (bar) magnet, or a magnetised needle on a cork floating in water.

True or false? A phone app measuring magnetic field strength on a table with no magnets nearby should read zero.

False. It still measures the Earth's magnetic field.