Question

What statement about the direction of the Earth's magnetic field is true?

A. The Earth's magnetic field has remained constant over time.
B. The Earth's magnetic field has reversed frequently over Earth's history.
C. The Earth's magnetic field has only reversed once over the course of Earth's history.
D. The Earth's magnetic field rotates randomly over time.
E. The Earth's magnetic field cannot presently be determined.

Answer 1

The Earth's magnetic field has reversed its poles many times over its history, with the most recent flip occurring roughly every 200,000 years. The correct option is B.

Step-by-step explanation:

The correct statement about the direction of the Earth's magnetic field is: B. The Earth's magnetic field has reversed frequently over Earth's history. This means that the magnetic north and south poles have switched places numerous times.

The direction of the Earth's magnetic field is thought to be caused by flowing liquid metals in the outer core, leading to electric currents and thus a magnetic field.

Additionally, the field does not remain constant; the magnetic poles shift slightly over time. Moreover, magnetic field lines never cross and are continuous, forming closed loops from the north pole to the south pole of a magnet. The correct option is B.