Science · 6 pages · 12 min
Why compasses misbehave near the poles
Near the magnetic poles the field is nearly vertical, so a level needle has little to follow.
When the purchase is complete, return to the original window. It will refresh.
From the opening
Compasses misbehave near the magnetic poles because the geomagnetic field there is nearly vertical. A compass needle is built to swing horizontally toward the horizontal part of the field, and that horizontal part shrinks away as the field tips downward. The opening covers why dip steals the level cue, what a dip needle shows instead, and why the geographic pole differs.
The rest of the brief — the later sections and the reading notes — opens after Stripe confirms payment.
Inside
- Why dip steals the level cue
- What a dip needle shows instead
- Why the geographic pole differs
- What local iron adds on top
- Where the idea stops applying
- A distinction worth keeping
Sources
- Magnetic inclination near the poles
- The horizontal component of the geomagnetic field