Question

few iron nails and screws got mixed with the wooden shavings while a carpenter was working with them.how can you help him in getting the nails and screws back from the scrap without wasting his time in searching with his friends?

Answer 1

by magnetic separation we can separate them because the nails and screws are made of iron.

Answer 2

In the case of magnets unlike poles attract and unlike poles repel. There is a large South magnetic polarity in the so called North of the Earth. So when a magnet is freely suspended it's north pole gets attracted by the magnetic south polarity of the Earth (in the north direction) and it points to the North directon.