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The force on a compass due to the Earth's magnetic field is relatively weak. Think of it as a gentle magnetic breeze.

Magnetic Wind

However the field near the household magnet is dense like a tornado. Strong near the magnet and very weak as you move away

Magnetic Wind

Challenge 1: How strong is the Earth's magnetic field?

Find (or make) a compass & 1 household magnet.

Bar Magnet

Compass

Can you determine the exact distance at which the household magnet force equals that due to the Earth's magnetic field?

What does this distance tell us?