Suppose a man proposes a theory that the earth's magnetic field is due to permanent magnetisation field is due to permanent magnetisation of molten iron core of earth. Will you acceept this theory? Give reasons for your answer.

Explain the terms the magnetic field due to earth at a point.

Due to earth's magnetic field, the charged cosmic rays particles

Lines of force, due to earth's horizontal magnetic field are.

Assuming that the earth's magnetic field is due to large circular loop of current in the interior of the earth, what is the plane of the loop and what is the direction of current around it?

An iron bar is magnetised with the help of another magnet or by subjecting it to a magnetising field. The magnetism acquired by the magnet is assumed due to the alignment of molecular magnet. Does the length to the iron bar undergo a change during the magnetisation process?

Answer the following questions regarding earth’s magnetism: f you made a map of magnetic field lines at Melbourne In Australia, would the lines seem to go Into the ground or come out of the ground?

A short bar magnet placed in a horizontal plane has its axis aligned along the magnetic north-south direction. Null points are found on the axis of the magnet at 14 cm from the centre of the magnet. The earth’s magnetic field at the place is 0.36 G and the angle of dip is zero. What is the total magnetic field on the normal bisector of the magnet at the same distance as the null-point (i.e., 14 cm) from the centre of the magnet? (At null points, field due to a magnet is equal and opposite to the horizontal component of earth’s magnetic field.)

The earth's magnetic field may be considered to be due to a short magnet placed at the centre of the earth and oriented along the magnetic south-north direction. the ratio of the magnitude of the magnetic field on the earth's surface of magnetic equator to that at the magnetic poles