Hand Battery

From: DonRath@aol.com
Date: Mon Feb 24 2003 - 11:03:59 PST

Dear Ms. Copeland,

Probably the easiest place to get the aluminum and copper for the hand
battery is the kitchen. You can try the bottom of an aluminum pan or a piece
of aluminum foil, and the bottom of a Revereware or other copper-bottomed
pan. Be sure you make a good electrical connection between the meter leads
and the metals (maybe tape them in place if necessary --also, be sure that
that the metal surfaces are clean -- a dirty, greasy, or badly oxidized
surface could block the flow of current).

Another source is home improvement (Home Depot, etc.) or hardware stores.
Aluminum "flashing" is used to prevent leaks on roofs and around windows.

A third source is a high school science department. The chemistry or physics
teacher may have pieces of aluminum and copper sheeting used for various
purposes, and might be willing to lend your daughter a piece.

Lastly, I don't know what grade your daughter is in, but perhaps her own
science teacher or school is a possible source.

Here are a couple of excerpts from replies I've made in the past couple of
years to questions about Hand Battery. Maybe they'll be helpful to your

I used a piece of aluminum foil (ordinary kitchen foil,
right out of the box)...For the other
metal I used the copper bottom of a Revereware frying pan. I first used an
inexpensive ($17) digital multimeter. The lowest current range on the meter
was 200 microamps, and I got reading of about 20 microamps on this scale. I
then switched to the 20 volt scale and got a reading of about 0.8 volts. I
then also tried the same materials with an old analog meter (I got it in
1960!) and got similar readings on the 50 microamp and 5 volt scales. I tried
putting my hand on both the shiny and dull sides of the foil, but there
wasn't an appreciable difference that I could notice. When I dampened my
hands on a sponge, though, the readings were up to twice as large.
The hand battery provides very little current. Some multimeters (usually
inexpensive analog meters, with a pointer that moves) require more current to
make the pointer move than the hand battery can supply. If your multimeter
has a scale labeled 100 microamps or less (this is the same as 0.1 milliamps,
or 0.1 ma), then you might be able to get a current reading.

Alternatively, you might try to get access to a digital multimeter. These
generally require much less current to operate, and should do better for you
-- relatively inexpensive versions can now be found, or maybe you can borrow
Hope this helps. Good luck!
Don Rathjen
Exploratorium Teacher Institute

This archive was generated by hypermail 2.1.3 : Mon Apr 24 2006 - 11:34:50 PDT