Explain briefly how moving electric charges at an atomic level produce magnetically polarized domains in a sample of iron, and how the domain structure differs for a magnetized iron bar and one that is not magnetized.

Explanation:

The domains of the non magnetic material are not aligned in one direction.

The current carrying conductor creates magnetic field around it.

The moving charge produces the magnetic field. The rate of flow of the charges constitutes the electric current.

Iron is a ferromagnetic material. The magnetic domains is responsible for magnetic behavior in uniform direction. The magnetic domain is a region in a magnetic material in which the magnetization is in uniform direction.

When the sample of iron is placed near the current carrying conductor then the iron gets magnetized. The domains of the iron gets aligned in the same direction.

b) phosphorus pentoxide

the area between the graph and the t axis