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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


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?