Answer the following questions:The earth’s core Is known to contain Iron. Yet geologists do not regard this as a source of the earth’s magnetism. Why?

Answer the following questions:The charged currents in the outer conducting regions of the earth’s core are thought to be responsible for earth’s magnetism. What might be the ‘battery’ (i.e., the source of energy) to sustain these currents?

Answer the following questions: The earth’s magnetic field varies from point to point in space. Does it also change with time? If so, on what time scale does it change appreciably?

Why do we often regard the potential of the earth to be zero?

Answer the following questions:The earth’s field departs from its dipole shape substantially at large distances (greater than about 30,000 km). What agencies may be responsible for this distortion?

Answer the following questions:The earth may have even reversed the direction of Its field several times during its history of 4 to 5 billion years. How can geologists know about the earth’s field in such distant past?

Answer the following questions regarding earth’s magnetism:Geologists claim that besides the main magnetic N-S poles, there are several local poles on the earth’s surface oriented In different directions. How Is such a thing possible at all?

Answer the following questions regarding earth’s magnetism: In which direction would a compass free point to, If located right on the geographic north or south pole?

Answer the following questions regarding earth’s magnetism:The earth’s field, It Is claimed, roughly approximates the field due to a dipole of magnetic moment 8 xx 10^22 J "T1 located at Its centre. Check the order of magnitude of this number In some way.