The magnetic field for compasses and the Earth is flipped.

The magnetic field for compasses and the Earth is flipped.

• A. False
• B. True
• C. It depends on the location
• D. Not enough information

Answer: (B)

Understanding how a compass works helps unravel this. A compass needle aligns with the local magnetic field because its north-seeking end is attracted to the Earth’s magnetic south pole. The Earth behaves like a giant magnet with its magnetic south pole located near the geographic North Pole. Field lines go from the Earth’s magnetic north to its magnetic south, so at the surface the direction a compass points ends up toward geographic north. In that sense, the compass reading appears “flipped” if you picture north pointing to magnetic north, not to the magnetic south that sits by geographic north. This arrangement is a global feature (with small local anomalies), so there is enough information to conclude that the statement is true.

Understanding how a compass works helps unravel this. A compass needle aligns with the local magnetic field because its north-seeking end is attracted to the Earth’s magnetic south pole. The Earth behaves like a giant magnet with its magnetic south pole located near the geographic North Pole. Field lines go from the Earth’s magnetic north to its magnetic south, so at the surface the direction a compass points ends up toward geographic north. In that sense, the compass reading appears “flipped” if you picture north pointing to magnetic north, not to the magnetic south that sits by geographic north. This arrangement is a global feature (with small local anomalies), so there is enough information to conclude that the statement is true.