Series & Parallel Circuits (OCR A Level Physics): Revision Note

Analysing Series & Parallel Circuits

Current

• In a series circuit, the current is the same for all components

• In a parallel circuit, the current is split across the different branches (or junction). The total current into a junction must equal the total current out of a junction

  • The amount of current in each branch depends on the total resistance of the components within that branch

Potential Difference

• In a series circuit, the e.m.f of the power supply is shared amongst all the components in different amounts, depending on their resistance

• In a parallel circuit, the voltage of all the components in each branch is equal to the e.m.f of the power supply

Summary

• A summary of the current, voltage and resistance within a series and parallel circuit are summarised below:

Table of Voltage, Current & Resistance in Series & Parallel Circuits