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Magnetic Declination Formula:
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Magnetic Declination is the horizontal angle between true north and magnetic north at the time of observation. It represents the angular difference between the direction a compass needle points (magnetic north) and true north.
The calculator uses the Magnetic Declination formula:
Where:
Explanation: The formula calculates the angular difference between magnetic bearing and true bearing, which gives the magnetic declination value.
Details: Accurate magnetic declination calculation is crucial for navigation, surveying, and mapping applications. It ensures proper alignment between magnetic compass readings and true geographic directions.
Tips: Enter magnetic bearing and true bearing values in radians. The calculator will compute the magnetic declination, which can be positive (east) or negative (west) depending on the relationship between magnetic and true north.
Q1: What is the difference between magnetic bearing and true bearing?
A: Magnetic bearing is measured relative to magnetic north, while true bearing is measured relative to true north. The difference between them is the magnetic declination.
Q2: Why does magnetic declination vary by location?
A: Magnetic declination varies because the Earth's magnetic field is not uniform and changes over time and location due to geological factors and magnetic field variations.
Q3: How often does magnetic declination change?
A: Magnetic declination changes gradually over time due to shifts in the Earth's magnetic field. The rate of change varies by location but is typically a few minutes per year.
Q4: What does a negative magnetic declination indicate?
A: A negative magnetic declination indicates that magnetic north is west of true north, while a positive value indicates magnetic north is east of true north.
Q5: How accurate is this calculation method?
A: The calculation provides the mathematical relationship between the bearings. For precise navigation, current magnetic declination data from updated sources should be used as the Earth's magnetic field constantly changes.