You are provided with two similar bars, one is a magnet and the other is a soft iron bar. How will you distinguish between them without the use of any other magnet or bar?

[Hint: A magnet when suspended freely will rest only in north-south direction, but soft iron bar will rest in any direction]

Explain the mechanism of attraction of iron nails by a magnet when brought near them.

Figure given below shows a bar magnet placed on the table top with it's north pole pointing towards south. The arrow shows the north-south direction. There are no other magnets or magnetic material nearby.

(a) Insert two magnetic field lines on either side of the magnet using arrow head to show the direction of each field line.

(b) Indicate by crosses, the likely positions of the neutral points.

(c) What is the magnitude of the magnetic field at each neutral point? Give a reason for your answer.

Explain what do you understand by magnetic induction. What role does it play in attraction of a piece of iron by a magnet?