The Theory That Describes How Earth's Magnetic Field Is Created

question 139

Multiple Choice

The theory that describes how Earth's magnetic field is created:

• A) is called the dynamo theory and is well established.
• B) depends on Earth's interaction with the Sun.
• C) depends heavily on friction between the surface and the atmosphere.
• D) is still being developed.

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Definitions:

Positron-Emission Tomography

A nuclear medicine functional imaging technique used to observe metabolic processes in the body as an aid to the diagnosis of disease.

Radioactive Isotope

An isotope of an element that has an unstable nucleus and emits radiation during its decay to a stable form.

Fluorodeoxyglucose

A radioactive tracer used in positron emission tomography (PET) imaging to observe metabolic processes in the body.

Positrons

Antiparticles of electrons, possessing the same mass as an electron but with a positive charge.