Inventor's Lab BUILD YOUR OWN FLASHLIGHT

DOI: 10.4324/9781003239284-10

MATERIALS

• » Cardboard tube
• » Copper wire with plastic coating (6-7 inches long)
• » Two D-cell batteries
• » Electrical tape
• » A flashlight lightbulb (2.2 or 3.0 volt)
• » 1 square of heavy dark paper cut slightly larger than the end of the cardboard tube
• » Paper cup with bottom cut out

First, strip the plastic coating off the end of the wire. Make sure you have at least 1/2 inch of exposed copper wire. Next, tape the paper over one end of the paper tube to form a bottom for your flashlight.

Use the electrical tape to secure one end of the wire to the bottom or negative end of the first battery. Make sure it's on tight. Then insert the battery with the wire taped to the end into the cardboard tube. Make sure you put the wired end in first so it sits at the bottom of the tube. Gently pull the wire up so that it sticks out the open end of the tube, and hold it against the wall of the tube.

Then, insert the second battery—make sure the negative end of the battery is down and touching the positive end of the first battery so there will be a complete electrical circuit.

Take the lightbulb to the top of the second battery. Make sure the metal bottom of the lightbulb is touching the positive post of the battery. Also, leave some of the metal on the side of the lightbulb exposed so that you can touch it with the wire.

Take the end of the wire that is poking out of the tube and touch it to the lightbulb. This should complete the electric circuit and the bulb will glow. Tape the wire to the bulb. If you want to turn off the bulb, then just peel oft the tape and move the wire away from the lightbulb.

Finally, tape the cup to the top of the tube to give your flashlight a cover.

Congratulations! You just built your own flashlight!