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.

What is Voltage ?

 Voltage, often referred to as electric potential difference, is a measure of the electric potential energy per unit charge between two points in an electric circuit. It is typically measured in units of volts (V).

Voltage represents the force or "push" that drives electric charges (electrons) to move through a conductor. It is analogous to pressure in a fluid system: just as pressure causes fluid to flow through a pipe, voltage causes electric current to flow through a conductor.

Mathematically, voltage (V) can be expressed using Ohm's law:

$𝑉=𝐼\times 𝑅$

Where:

• $𝑉$ is the voltage in volts (V),
• $𝐼$ is the current in amperes (A),
• $𝑅$ is the resistance in ohms (Ω).

In simple terms, voltage describes the difference in electric potential energy between two points in a circuit. When a voltage is applied across a conductor, it creates an electric field that exerts a force on electric charges, causing them to move and thereby generating electric current.

Voltage plays a fundamental role in electricity and is crucial for understanding and analyzing electrical circuits, as well as for the operation of electrical devices and systems.