COMPASSES AND HOW THEY WORK

At the center of the Earth spins the Earth's core. The core is made up of mostly iron. The outer portion of the core is liquid iron that spins and makes the earth into a giant magnet. This is very useful to us here on Earth as it lets us use magnets in compasses to find our way and make sure we are heading in the right direction. It's also useful to animals such as birds and whales who use the Earth's magnetic field to find the right direction when migrating.

Compasses you buy are a bit more sophisticated than floating needles but work essentially the same way. They have a lightweight, magnetized pointer mounted on a very low-friction pivot that is sealed inside a small plastic cylinder filled with liquid.

That's all there is to a compass: the red pointer in a compass is a magnet and it's being attracted by Earth's own magnetism (sometimes called the geomagnetic field—"geo" simply means Earth).

VIDEO TIME
https://m.youtube.com/watch?v=Aq8s2SF17zY

QUESTIONS

• Can you name 2 other use of Earth’s magnetic field?
• How does Earth have a magnetic field?

BIBLIOGRAPHY

• https://www.explainthatstuff.com/how-compasses-work.html
• https://www.ducksters.com/science/magnetism.php

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