Describe how could you use an electromagnete to sort a mixture of iron and copper pieces into two seprate piles of iron and copper

Electromagnetic cranes are used to separate copper from iron in a scrap yard. The current is switched on to energies the electromagnet and pick up the iron pieces from the scrap. Then these iron pieces are moved to another position, the electromagnet in switched off and the iron pieces are released.

Explanation:

when heated, the valance electrons increased their speed and transferred the heat from electron to electron.   i just took the test.