Concepts of Physics

IIT JEE Physics (1978-2018: 41 Years) Topic-wise Complete Solutions

Test Strength of a Magnet?

Introduction

Magnetism is the property of some materials to attract objects made of iron, nickle, cobalt etc.

Apparatus

bar magnet, small nails (pins), a long nail

Procedure

Place small nails in a heap on a table. Touch a bar magnet on the long iron nail and then bring the pointed end of the nail near the heap of small nails. The small nails will cling to the long nail and form a chain. Remove the magnet from the long nail. The small nails will immediately fall.

fca.jpg

Discussion

When the magnet touches the long iron nail, it becomes a magnet. Hence it attracts the small nails or any other magnetic material. The long nail will attract the small nails as long as bar magnet touches the long nail. The nail becomes the temporary magnet. The process of temporary magnetization is called induction. The tiny molecular magnets in the iron nail align themselves systematically as long as the magnet touches the nail, but orientation of these molecular magnets becomes random when the magnet is removed.

Note

How to compare strength of two magnet?