Electric Currents in Conductors – Class 12 | Chapter – 3 | Physics Short Notes Series PDF for NEET & JEE

Electric Currents in Conductors: Electric current is the flow of electric charge in a conductor. Conductors are materials that allow electric charge to flow through them easily. Some common conductors include metals such as copper and aluminum. In a conductor, electric current is the result of the movement of negatively charged electrons. Electrons are negatively charged particles that are found in the outermost shell of an atom. When an electric potential difference is applied across a conductor, such as a wire, the electrons within the wire become excited and begin to flow from one end of the wire to the other.

The flow of electric current is typically measured in units of Amperes (often abbreviated as “amps”). The rate of flow of electric charge is proportional to the electric current, and can be expressed mathematically as the product of the current and the electric charge of the electrons that are flowing.

Electric Currents in Conductors


Conductors are materials that allow electric charge to flow through them easily. Some common conductors include metals such as copper, aluminum, gold, and silver. These materials are considered good conductors because they have a high number of free electrons in their outermost shell, which can move freely and carry electrical charge. The conductivity of a material is a measure of how well it conducts electric current. The conductivity of a material is influenced by several factors, including the type of material, the temperature of the material, and the presence of impurities or defects.

Conductors play a crucial role in many electrical and electronic devices, including wires, batteries, and electrical circuits. They are used to carry electrical signals, transmit power, and store energy. By understanding the properties of conductors and how they behave, engineers and scientists can design and build more efficient and effective electrical and electronic devices.


Insulators are materials that do not conduct electricity well. They have a low number of free electrons, which makes it difficult for electrical charges to flow through them. Some common insulators include rubber, plastic, glass, air, and dry wood. Insulators are used in a variety of applications, such as electrical wiring and cable insulation, electrical equipment insulation, and insulation in high-voltage power transmission systems. They are used to protect electrical components from damage, prevent electrical shock, and prevent the loss of energy through heat.

Insulators are also used to isolate electrical components from each other, to ensure that electrical signals do not interfere with each other and to maintain the integrity of the electrical signals being transmitted. For example, in a high-voltage power transmission system, insulators are used to prevent electrical charges from jumping from one wire to another, which can cause sparks and damage to the system.

Types of Electric Currents in Conductors

There are two main types of electric currents in conductors:

  • Direct current (DC) is a flow of electric charge in a single, constant direction. Direct current is commonly found in batteries and other electrical devices that produce a constant voltage. Direct current is also used in some electrical applications, such as charging electric vehicles and electrolysis.
  • Alternating current (AC) is a flow of electric charge that periodically changes direction. Alternating current is commonly found in the electrical grid and is used to transmit electrical energy over long distances. AC is preferred over DC for power transmission because it can be easily transformed into different voltages, allowing for more efficient energy transfer over long distances. There are also several types of alternating current, including single-phase AC, two-phase AC, and three-phase AC. Single-phase AC is commonly used in household electrical systems, while three-phase AC is used in industrial and commercial applications, such as motors and generators.

Biology Quiz & Notes Physics Quiz & Notes Chemistry Quiz & Notes

Follow on Facebook

By Team Learning Mantras