Current & Voltage Course

Lesson 10 of 16: Parallel Circuit Basics

Move step by step through the course and keep track of where you are.

Simulation

Parallel Circuit Basics

A parallel circuit has multiple paths, so current can split while each branch still sees the same source voltage.

Voltage

12.0 V

I1

2.00 A

I2

1.00 A

I3

0.67 A

Branch Rule

2.00A + 1.00A + 0.67A = 3.67A

Core idea

In parallel, each branch gets the full source voltage, and the total current is the sum of the branch currents.

Simple idea

Same source voltage appears across every branch, while the current divides between the available paths.

Parallel circuit

Each branch connects across the same top and bottom rails, so the source voltage appears across every branch.

Three-branch parallel circuitThe same voltage appears across R1, R2, and R3, while the total current splits between the branches.+12 V12R16.0 Ohm12R212.0 Ohm12R318.0 OhmTotal Current = 3.67 AFlow Strength: 92%Level: High
Circuit View

Watch the branch currents split

This simulation shows how the same source voltage appears across every branch while the total current divides between the available paths.

Same voltage

12.0 V

Every branch is connected across the same source, so each branch receives the full supply voltage.

Total current

3.67 A

Branch currents add together, so the source current becomes the total of all branch currents.

Equivalent resistance

3.27 Ohm

More parallel paths lower the overall resistance seen by the source.

What to notice

In a parallel circuit, the voltage stays the same across each branch. What changes is the branch current, and those branch currents combine to make the total source current.

Beginner Summary

Keep the branch idea in mind

This lesson becomes easy when you remember one simple picture: a parallel circuit gives current more than one path, while each branch still sees the same source voltage.

Same voltage across every branch. Different branch resistance can create different branch currents.

Same voltage

Each branch connects across the same source, so every branch gets the full supply voltage.

Current splits

Current divides between the branches, and the lower-resistance branch takes more current.

More paths

Adding more parallel paths lowers the equivalent resistance and increases the total source current.