Differences & Similarities Between a Series Circuit & a Parallel Circuit

Series and parallel circuits treat voltage and current differently.
••• Jupiterimages/Photos.com/Getty Images

Electricity is created when negatively charged particles, called electrons, move from one atom to another. In a series circuit, there is just a single path along which electrons can flow, so a break anywhere along the path interrupts the flow of electricity in the entire circuit. In a parallel circuit, there are two or more branches, creating separate pathways along which electrons can flow, so a break in one branch does not affect the flow of electricity in the others.

Current

In a series circuit, the current anywhere in the circuit is defined by the most important and basic law of electricity, known as Ohm’s Law. Ohm’s Law states that I = V/R, where I represents electrical current, V represents the voltage supplied by the source and R represents the total resistance -- opposition to the flow of electric current -- of the circuit. In a parallel circuit, the current in each branch of the circuit is inversely proportional to the resistance of each branch, and the total current is equal to the sum of the currents in each branch.

Voltage

In a series circuit, the potential difference, or voltage -- the force that “pushes” the electrons around -- decreases across each component in the circuit. The voltage drop across each component is proportional to its resistance, such that the sum of the voltage drops is equal to the total voltage supplied by the source. In a parallel circuit, each component effectively connects the same two points of the circuit, so the voltage each component is the same.

Resistance

In a series circuit, the total resistance is simply the sum of the resistances of the components connected to the circuit. In a parallel circuit, the fact that current can flow along more than one pathway means that the total overall resistance is lower than the resistance of any single component. The total overall resistance, Rt, can be calculated from the equation Rt = R1 + R2 + R3 … Rn, where R1, R2, R3 and so on are the resistances of the individual components.

Similarities

Aside from the fact that they are both used to connect electrical components, such as diodes, resistors, switches and so on, together, there are few similarities between serial and parallel circuits. Series circuits are designed so that the current through each component is the same, whereas parallel circuits are designed so that the voltage through each component is the same.

Related Articles

What Are Two Types of Electrical Circuits?
Similarities & Differences Between Ionic & Covalent
How to Find Voltage & Current Across a Circuit in Series...
Parallel Circuit Problems
Disadvantages to a Parallel Circuit
Definition of a Simple Electrical Series Circuit
The Characteristics of a Parallel Circuit
How to Calculate a Voltage Drop Across Resistors
How to Understand Voltage Drops & Resistors
How to Calculate Output Voltage
How to Calculate Amperage in a Series Circuit
What Are Two Types of Electrical Circuits?
How to Calculate Potential Difference
How to Calculate the Amps and Resistance of a Parallel...
What Is Ohm's Law & What Does It Tell Us?
How to Wire a Battery in Series
The Advantages & Disadvantages of Series and Parallel...
How to Determine the Primary & Secondary of a Transformer
How to Calculate IRMS
How to Calculate Millivolts from Microsiemens
What Is DC & AC Resistance?