Adult supervision recommended.
What You Need:
- Pint glass canning jar with lid
- 3 feet insulated copper wire
- 6-volt battery
- Thin iron wire (unraveled picture hanging wire works great)
What You Do:
1. Cut the copper wire in half and strip at least one inch of insulation off the ends of each length of wire. Next, punch two holes in the jar lid. (You can use a nail for this.) Thread one end of the wire through each hole in the lid.
2. Make a hook at the end of each wire (the end that will be inside the jar when you put the lid on). Twist two or three strands of the iron wire together, then twist the ends around the hooks in the copper wire. The iron wire will act as your filament.
3. Place the lid (with the filament and wires attached) in the jar and carefully connect the free ends of the copper wire to the terminals on the 6-volt battery. Once both ends are connected to the battery, the current should start flowing, causing the filament to heat up and give off a bright orange glow.
Your homemade light bulb is working! The light will last for anywhere from a few seconds to a few minutes, depending on your filament. (Note: once your filament is burned out, don’t touch it right away – it will be very hot.)
- You might also be interested in our Make a Pinhole Camera and Make a Vacuum Cleaner projects.
