Answer:
The dynamo theory proposes a mechanism by which a celestial body such as Earth or a star generates a magnetic field. Earth's crust core contains a large amount of iron and nickel is evidence of the dynamo theory. Dynamo theory proposes a mechanism by which a celestial body such as the Earth or a star generates a magnetic field. The thesis describes how a rotating, convecting, and electrically conducting fluid can maintain a magnetic field over astronomical time scales. In this dynamo mechanism, fluid motion in Earth's outer core moves to execute material (liquid iron) across an already existing weak magnetic field and generates an electric current. (Heat from radioactive decay in the core is thought to induce convective motion.