Chapter 24.1, Problem 18SSC

(a)

To determine

The reason behind the behavior of the rods.

Explanation of Solution

Introduction:

A magnet is a material in which domains are aligned in one direction and so, it is able to attract other magnetic materials. A magnet has two poles- a pole is called North pole and another is called South pole. A rule for magnetism is that identical poles repel each other and different poles attract each other. So, for two magnets, if their north poles or else south poles face each other, they will repel each other. If the north pole is towards the south pole of another, they will attract.

The metal rods would be magnet. When they float one above the other, their poles would be in same direction so that the rods repel each other. When the direction of a rod is reversed, the opposite poles attract each other and hence, the top rod falls on the bottom one.

Conclusion:

The metals rods would be magnet.

(b)

To determine

The type material used in replacement rod.

Explanation of Solution

Introduction:

A magnet is a material in which domains are aligned in one direction and so, it is able to attract other magnetic materials. A magnet has two poles- a pole is called North pole and another is called South pole.

The replacement rod would be made up of magnetic material like nickel, cobalt, iron etc. These materials get attracted towards the other rod which is a magnet.

Conclusion:

The replacement rod would be made up of magnetic material like nickel, cobalt, iron etc.