Question

Which of the following is not a magnetic material?
A. Steel
B. Copper
C. Nickel
D. Cobalt

Answer 1

Hint:We know that the materials which can be either attracted or repelled when placed in an external magnetic field and can be magnetized themselves are called the magnetic materials. To solve this question, we need to know about the given options. After understanding a few characteristics of every material given in the options, we can determine the correct answer.

Complete answer:
We will consider every option one by one.
Steel: Steel has ferromagnetic properties as it is derived from iron. Most steels are attracted to a magnet. In some cases, steel can also be used to make permanent magnets.
Copper: Copper itself is not magnetic but interacts with magnets to some extent. This property is useful to generate electricity in power plants.
Nickel: Nickel has properties like iron, its compounds are present in the earth’s core. Because of its magnetic properties, nickel is also part of Alnico magnets which are made of aluminium, nickel, and cobalt. These magnets are stronger than rare-earth metal magnets but weaker than iron-based magnets.
Cobalt: Cobalt is an important ferromagnetic metal. Cobalt can be used to produce soft as well as hard magnets. Thus, we can say from this information that copper is not a magnetic material.

Hence, option B is the right answer.

Note: We have seen three magnetic materials in which we have used the term ferromagnetic. Generally, magnetic materials can be classified in three groups:ferromagnetic, paramagnetic and diamagnetic. While ferromagnetic metals are strongly attracted by magnets, paramagnetic metals attract weakly. Diamagnetic materials, on the other hand, show a weak repulsion when placed near a magnet. Thus, we can say that only ferromagnetic metals are considered truly magnetic.