circuit cell, battery
bulb wire
filament current
contact point A threaded base B
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A circuit is like a circle of electricity, which goes from the cell, through the wire and back to the cell (also called the "source").
A circuit has three parts:
1. the cell, or battery, where the electricity comes from
2. the bulb, which changes (or converts) the electricity into light
3. the wire, which makes a path for the electricity to travel in
cell
Here is a picture of a bulb.
The filament is the little wire inside the glass that makes the light. The bulb lights when it is part of a circuit.
1. the electric current goes into the bulb at contact point A
2. up the little wire in the base to the filament
3. along the second wire down to the threaded base B
4. the current leaves the metal base
* The current can also flow through the bulb in the opposite direction.
* Contact point A and part of the threaded base B must be touching the rest of the circuit for the bulb to light.
THE CONTACT POINTS
= what must touch to make the bulb light
Two points on the cell and two points on the bulb must be part of the circuit if the bulb is to light.
cell:
* the top of the cell ( + positive)
* the bottom of the cell ( - negative)
bulb:
* contact point A on the bottom of the bulb
* threaded base B of the bulb