What is Resistance ?

 Resistance is a measure of the opposition that a material or component offers to the flow of electric current. It is typically denoted by the symbol

$𝑅$ and measured in units of ohms ($\mathrm{\Omega }$).

Resistance arises due to the interactions between the electric charges (typically electrons) and the atoms or molecules in a material. These interactions impede the flow of electric current, converting some of the electrical energy into heat. The greater the resistance, the more difficult it is for current to flow through a material or component.

The relationship between voltage ($𝑉$), current ($𝐼$), and resistance ($𝑅$) is described by Ohm's law:

$𝑉=𝐼\times 𝑅$

Where:

• $𝑉$ is the voltage across the component in volts (V),
• $𝐼$ is the current flowing through the component in amperes (A),
• $𝑅$ is the resistance of the component in ohms ($\mathrm{\Omega }$).

Ohm's law states that the voltage across a component is directly proportional to the current flowing through it, with the proportionality constant being the resistance. In other words, if the resistance of a component remains constant, doubling the voltage across it will double the current flowing through it, and vice versa.

Resistance is a fundamental property of electrical components and materials and plays a crucial role in determining the behavior and performance of electrical circuits. It is used in various electronic devices, such as resistors, to control the flow of current and to achieve specific electrical characteristics.