Explain what a magnetic field is and its force.

G00gle

Explanation: Magnetic force, attraction or repulsion that arises between electrically charged particles because of their motion. The magnetic force between two moving charges may be described as the effect exerted upon either charge by a magnetic field created by the other.

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.