Which term best defines "magnetic variation"?

Which term best defines "magnetic variation"?

• A. The distance between two navigational points
• B. The angular difference between true north and magnetic north
• C. The change in wind speed at different altitudes
• D. The difference in temperature at sea level versus altitude

Answer: (B)

Magnetic variation, also known as magnetic declination, specifically refers to the angular difference between true north (the geographic north pole) and magnetic north (the direction a magnetic compass points). This difference arises due to the Earth's magnetic field, which does not align perfectly with its rotational axis. Understanding magnetic variation is crucial for navigation, especially when using a compass, as it allows navigators to correct for this discrepancy and accurately determine their true heading. The other options present concepts that are unrelated to magnetic variation. Distance between navigational points pertains to distance measurement, not directional difference. Changes in wind speed at different altitudes deal with meteorological patterns, and temperature differences at sea level versus altitude involve atmospheric science, none of which capture the essence of magnetic variation.

Magnetic variation, also known as magnetic declination, specifically refers to the angular difference between true north (the geographic north pole) and magnetic north (the direction a magnetic compass points). This difference arises due to the Earth's magnetic field, which does not align perfectly with its rotational axis. Understanding magnetic variation is crucial for navigation, especially when using a compass, as it allows navigators to correct for this discrepancy and accurately determine their true heading.

The other options present concepts that are unrelated to magnetic variation. Distance between navigational points pertains to distance measurement, not directional difference. Changes in wind speed at different altitudes deal with meteorological patterns, and temperature differences at sea level versus altitude involve atmospheric science, none of which capture the essence of magnetic variation.