Idea 1of 9Builds onThe ability to make change
A loop that closes
A battery, a wire, a bulb. Why does it light?
Today you'll discover
- what a battery needs before anything happens
- why a gap anywhere stops everything
- the name for a loop that closes
Think firstA battery and a bulb, joined by one wire
A battery and a bulb are joined by one wire only. Does the bulb light?
Decide first, then press Next. Trace the path from the battery and back to it.
A rectangular loop of wire with a battery on the left, drawn as a long and a short bar, and a bulb on the top wire. After a prediction, the battery is marked, then the wires before and after the bulb are marked to show flow on both. The last step asks what happens when the wire is cut after the bulb.
See the whole ideathe big idea and the key word, in one place
The big idea
A circuit is a closed loop; break it, everything stops.
Easy to get wrongA gap anywhere stops everything, not just the part beyond the gap. The flow is one loop, and a loop with a gap is not a loop.
Key word
- circuit
- a closed loop that charge can flow around; break it anywhere and the flow stops everywhere
About this modelCharge is never used up: what leaves the battery comes back. Volts are what get spent.
Charge is never used up: what leaves the battery comes back. Volts are what get spent.
Ready to use it?
- Say whether a described arrangement of battery, wires and bulb is a complete circuit, and why.