Series and Parallel Circuits

Objective: Current in Series Circuits

In a series circuit, components are connected one after the other, forming a single path for the electric current. A fundamental property of series circuits is that the current is the same at every point in the circuit.

This is because the same amount of charge flows through each component in a series circuit. If the current were different at different points, it would imply that charge was either being added or removed from some parts of the circuit, which is not possible in a simple series connection.

Key Points about Current in Series Circuits

• The current (I) is constant throughout the entire series circuit.
• If one component's resistance changes, the total current in the circuit will also change.
• The voltage (V) across each component in a series circuit will be different and depends on the component's resistance.

Mathematical Representation

Ohm's Law applies to each component in a series circuit: $V = IR$

The total resistance (R_total) of a series circuit is the sum of the individual resistances:

$$R_{total} = R_1 + R_2 + R_3 + ...$$

Example

Consider a series circuit with a 12V battery and two resistors connected in series. If the current flowing through the circuit is 0.5 A, then the current flowing through each resistor is also 0.5 A.

Concept	Description
Current in Series	The electric current is the same at all points in a series circuit.
Reasoning	The same number of electrons flow through each component.
Total Resistance	In a series circuit, the total resistance is the sum of individual resistances.
Ohm's Law	$V = IR$ applies to each component in the series circuit.