Electric Current is the flow of electric charge through a conductor, measured in amperes (A). It represents the rate at which charge passes through a point in the circuit.

Voltage, also known as electric potential difference, is the force that pushes electric charges through a conductor, measured in volts (V). It represents the energy per unit charge.

Parallel Circuits are electrical circuits in which components are connected alongside each other, providing multiple paths for the current to flow.

In a parallel circuit:

• Voltage Across Components: All components share the same voltage. This means that the voltage across each parallel branch is equal to the source voltage.
• Current Distribution: The total current in the circuit is the sum of the currents flowing through each parallel branch.
• Independent Paths: Each branch operates independently. If one component fails, the others continue to function.

Ohm's Law relates voltage (V), current (I), and resistance (R) in an electrical circuit:

$V = I \times R$

In parallel circuits, since the voltage across each component is the same, Ohm's Law can be applied individually to each branch to determine the current through each component.

The total resistance ($R_{total}$) in a parallel circuit is found using the reciprocal formula:

$$\frac{1}{R_{total}} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} + \dots$$

For two resistors, this simplifies to:

$$R_{total} = \frac{R_1 \times R_2}{R_1 + R_2}$$

This formula indicates that the total resistance in a parallel circuit is always less than the smallest individual resistance.

The total current ($I_{total}$) supplied by the source is the sum of the currents through each parallel branch:

$$I_{total} = I_1 + I_2 + I_3 + \dots$$

This relationship is derived from Kirchhoff's Current Law, which states that the total current entering a junction equals the total current leaving the junction.

Electric power ($P$) consumed by a component in a circuit is calculated as:

$$P = V \times I$$

Since all components in a parallel circuit have the same voltage, the power consumed by each component depends on its individual current.

• Reliability: If one component fails, others continue to operate.
• Consistent Voltage: All components receive the same voltage, ensuring uniform performance.
• Scalability: Easy to add or remove components without affecting the entire system.

Parallel circuits are widely used in household electrical systems, where multiple appliances operate independently. They are also prevalent in electronic devices, automotive wiring, and power distribution systems.

For example, in a home, appliances like lights, refrigerators, and TVs are connected in parallel to ensure each operates at the same voltage supplied by the mains.

• Complex Calculations: Determining total resistance and current can become complicated with numerous branches.
• Unequal Load Distribution: Variations in resistance can lead to unequal current distribution, potentially overloading some components.

• In parallel circuits, voltage remains constant across all components.
• The total resistance decreases as more branches are added.
• Total current is the sum of currents through each parallel branch.
• Parallel circuits offer reliability and consistent performance.
• Understanding parallel circuits is crucial for practical electrical applications.