Magnetic Variation
What is magnetic variation?
Magnetic variation is the angular difference, measured in degrees, between true north (the geographic North Pole) and magnetic north (where a compass points) at a given location. Because this difference changes depending on where you are on Earth, you must apply the correct variation for your area when converting between true and magnetic directions. On the test: remember the rule "East is least (subtract), West is best (add)" when going from a true heading to a magnetic heading.
Also known as: variation, magnetic deviation (incorrect synonym—do not confuse with deviation)
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