BUILDING A CAPACITOR

I have some comments on this project and the cancelling of the sine and exponential projects—click here for my comments.

For this project, you will need to provide:

· A battery

· Paper, tin foil, wires, tape, and other junk

· Your multimeter

In this project, you are going to build a capacitor. There are many resources out on the web—especially some nice videos—to show you how to build simple capacitors using stuff like paper, aluminum foil, plastic bottles, and other junk.

Your task is to build your own capacitor, charge it with your battery, and then remove the battery and use your multimeter to show that your capacitor will hold charge. Any capacitor that holds charge as seen with your multimeter earns a grade of “B”. Any capacitor that will hold charge well enough to light a bulb or perform some other electrical function will earn an “A”.

What to do:

a) Build a capacitor—do the research, and make one. Take photos of the construction.

b) Measure the voltage of the battery with your multimeter (set to DC volts).

c) Charge the capacitor with the battery.

d) Disconnect the battery, and attach your multimeter (set to DC volts) to the capacitor, to measure whether the capacitor holds charge. If the capacitor will hold charge, the multimeter should show the same reading when hooked to the capacitor as it did when hooked to the battery. Of course, charge will bleed off through the multimeter, so the reading will likely decline with time. Adjusting your multimeter range may help slow the bleed-off.

e) If your capacitor is really good, you can use it to light a bulb or something, just like the battery will—at least until it runs out of charge.

WHAT TO TURN IN

#1) Photos of your capacitor being constructed (at least three) and a photo of your finished capacitor.

#2) A video of steps (b) through (e) above, showing that the capacitor will hold charge (send me the link).

#3) Two typed paragraphs. The first paragraph should describe what problems and successes you had in this project, and the second should discuss what you learned from this project.

It would be best if you can put the photos from #1 and the paragraphs from #3 into one WORD or PDF file, but I know not everyone has the tools to do that.

GRADES:

If your capacitor holds charge, your minimum grade is an 80%, maximum is a 90% (exact grade depends on photos and paragraphs).

If your capacitor holds charge and will light a bulb or do some other task, your minimum grade is a 95%, maximum is a 100% (exact grade depends on photos and paragraphs).

If your capacitor does not hold charge, keep working at it. These are pretty simple objects.