Question

electric current can flow through:
A. Silver
B. Copper
C. Iron
D. All of these

Answer 1

Hint:To answer this question, we must know about electric current and conductors so we can easily answer these types of questions. The flow of charges through a cross section per unit time is called electric current. The process of transferring electric current from one point to another through some medium is called conduction.

Complete answer:
The substance which allows electric current to flow through it is called a conductor.A good conductor of electricity is that material, which conducts electricity easily. This means that electric charges can easily flow through a good conductor. We know that flow of charges through a cross section per unit time is defined as current. We also know that when there is a difference between the electric potentials at two different points, then charges move from one point to another. Hence, we can say that there is a current when there is a potential difference.

Therefore, when we create some potential difference across a material, there will be current flowing through the material (because all materials have charges inside them). If a large amount of current is produced for a small potential difference, then we say that the material is a good conductor of electricity.

When it takes a large potential difference across the material for producing a small current in the material, we say that the material is a bad conductor of electricity. Good conductors of electricity are mostly metals.Metals given in the questions (silver, copper and iron) are good conductors of electricity.

Therefore, option D is correct.

Note:The materials that do not conduct electricity absolutely are called insulators.They do not conduct electricity even for the maximum value of potential difference. The materials which do not conduct electricity easily but conduct when subject to larger potential differences are called semiconductors.