Dip Needle Compass vs. Normal Compass

by qomoco
Tags: compass, needle, normal
qomoco is offline
Mar14-10, 04:34 PM
P: 12
Why does one "dips" down and the other rotates?
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ideasrule is offline
Mar14-10, 05:53 PM
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Did you try Google? Here's what a dip needle compass looks like:


I'm sure you know what a normal compass looks like.
qomoco is offline
Mar14-10, 07:56 PM
P: 12
I know what it looks like, I'm wondering "why"

mgb_phys is offline
Mar14-10, 08:28 PM
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Dip Needle Compass vs. Normal Compass

Why does it dip?
Because the magnetic field of the earth is mostly vertical, it goes out of one pole and into the other. For typical northern city the vertical component is about 4-5x larger than the horizontal, which is a real pain if you are trying to design a compass that can be used when tilted.
- that's why ships compasses are gimbaled to always float level when the ships tips

Why you would own one?
Mainly as an instrument to investigate/demonstrate the earth's field. You could use it to measure your latitude -although a sextant is easier.

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