What Earth layer is liquid and generates Earth's magnetic field?

What Earth layer is liquid and generates Earth's magnetic field?

• A. Mantle
• B. Outer core
• C. Inner core
• D. Crust

Answer: (B)

The magnetic field is produced by the motion of electrically conducting liquid iron in the planet’s outer core. In that layer, molten iron moves and circulates due to heat and composition differences, and Earth’s rotation twists these flows. This combination acts like a self-sustaining dynamo, converting kinetic energy into magnetic energy and maintaining the field over time. The mantle and crust are solid rocks and don’t offer the kind of large-scale, flowing, conductive movement needed for a global magnetic field, and the inner core, though iron-rich, is solid and cannot support the same convective circulation. That’s why the layer that is liquid and generates Earth’s magnetic field is the outer core.

The magnetic field is produced by the motion of electrically conducting liquid iron in the planet’s outer core. In that layer, molten iron moves and circulates due to heat and composition differences, and Earth’s rotation twists these flows. This combination acts like a self-sustaining dynamo, converting kinetic energy into magnetic energy and maintaining the field over time. The mantle and crust are solid rocks and don’t offer the kind of large-scale, flowing, conductive movement needed for a global magnetic field, and the inner core, though iron-rich, is solid and cannot support the same convective circulation. That’s why the layer that is liquid and generates Earth’s magnetic field is the outer core.