Electric Currents in Conductors


Electrical Conductors are a very important part of our lives. Our entire power grid is made up of electrical conductors and insulators. Recently we’ve added another term, ‘semiconductors’ to this list! How does electric conduction work? What happens when an electrical conductor conducts electricity?

Understanding Electric Current:

In the previous article, we understood how the movement of an electron creates an electric current. Imagine a body, invariably made up of atoms. The atoms are made of electrons, protons and neutrons. Due to being loosely connected, electrons are able to move freely inside the body, which is called electrical current. Under normal condition, the electrons are moving randomly inside the body and hence the net electric current is zero since they all cancel each other out.

The application of an electric field around the body is also another way to cause movement in electrons but the catch is that the electric field does not influence everything. This is where the distinction between electrical conductors and insulators comes in electricity. The electric field can cause the electrons to move around. Through this influence on electrons, we can give a net direction to the motion of the electrons. This is how we generate an electric current.

Visualizing Electric Current:

Electric Current

Imagine a circular rod made of an electrically conducting material. Apply an electric field of magnitude Q to it. This means that one end of the rods assumes a positive potential and one a negative potential. Since electrons are more mobile than protons, they rush to cancel out the positive potential developed at the left end of the rod. This motion of electrons is also called an electric current. According to scientific convention, electric current flows opposite to the direction of the flow of electrons.

Conductors:

Bodies in which the application of an electric field results in the generation of an electric current due to the movement of the electrons is called an Electrical Conductor. In such bodies, the electrons are free to move around inside the body and their random motion can be influenced by an electric field. Most electrical conductors are metals mainly because metals possess electrons in the outermost orbit where they are most loosely held and can move around easily. The wires supplying electricity to your houses are supplying fresh energetic electrons to your house for you to use. We have learn’t to use it and we have become completely dependent on electricity.

Insulators:

Certain bodies do not possess free moving electrons like metals. Materials with fixed electrons such as plastics and rubber do not respond to the electric field at all. The electrons in such materials is not free to move around and generate an electric current. Such bodies are called Electrical Insulators. The plastic coating around the wire is an insulating material which prevents you from getting shocked by the electricity in the wire within.

Electricity is vital to our lives. We may build our machines but electricity is what runs it.

Stay tuned with byju’s to learn more about conductors, insulators and many more.


Practise This Question

The magnitude of the focal length of a diverging less is 20 cm. What is the power of this lens?