A circuit is a path that lets electricity travel in a complete loop, from a power source, through parts, and back again.
What is a circuit? Think of a circuit like a road for electricity. A simple one has a battery (the power source), a switch, and a bulb.
The power source. The power source gives electricity its energy. Batteries are common in toys, flashlights, and fun gadgets; wall outlets and solar cells are power sources too.
The loop. Electricity needs a complete loop to keep moving. A complete loop works. A broken loop stops.
Switches. A switch opens or closes the path. When the switch is closed (on), the path is complete and electricity flows. When the switch is open (off), the path is broken and electricity stops.
What happens? When the loop is complete, devices work: lights light up, buzzers sound, and fans spin. Electricity can turn on lights, make sounds, create motion, and more. You see circuits in flashlights, desk lamps, toy cars, and doorbells every day.
Remember: a circuit is a complete loop, electricity must have a complete loop, and a switch decides if it's open or closed. Closed loop = go, broken loop = stop!
What to remember
- A circuit is a path for electricity.
- Electricity needs a complete loop to flow.
- A switch opens or closes the path.
- Closed loop = go; broken loop = stop.
Words to know
- Circuit
- A path that lets electricity flow in a loop.
- Power source
- Where the electricity comes from, like a battery.
- Switch
- A part that opens or closes the path.
- Loop
- A complete path that goes all the way around.
For grown-ups
An electric circuit is a closed loop through which current flows from a source (battery or outlet) through components and back. A switch makes or breaks that loop to control the flow: a complete (closed) circuit works, while an open one stops. Circuits are the foundation of essentially all electronics. For kids: electricity needs a full loop, and a switch decides whether the loop is open or closed.
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