The Human Battery

The Human Battery

Here’s a fun project for young scientifically-minded students who enjoy a good experiment. This project was completed and submitted by a customer, Gannon Boyd, who emailed the details to our customer service department.

Batteries are simple devices that store chemical energy and convert it to electrical energy. A battery consists of one or more voltaic cells, in various sizes and forms and are integrated into most electronic and portable devices.

Required materials
• Copper Plate
• Aluminum Plate
• Micro Ammeter (a measuring instrument used to measure the electric current in a circuit, can be found at your local Radio Shack store)
• 2 Alligator Clips (a temporary electrical connector, named for its resemblance to an alligator’s jaws)
• Lead Wire
• 2 Blocks of Wood
• 1 Human Volunteer

If you have set up the “Human Battery” properly, when you place your hands on each plate, an electric current is generated and indicated on the micro ammeter. If the meter doesn’t move, it’s possible the connections are wrong or not secure. In the case of no readings, try cleaning the plates and reversing the connections. Also, make sure both the copper and aluminum plates are clean before using them. Dirty plates can interfere in the experiment and prevent accurate results.

Step-By-Step Procedure

1. Mount the copper plate and the aluminum plate to separate blocks of wood.
2. Connect one of the Micro Ammeter’s terminals to the copper plate and attach with a alligator clip.
3. Connect the other Micro Ammeter’s terminal to the aluminum plate and attach with a alligator clip.
4. Have the human volunteer stand between the two plates and hold each one in their hands.

SECOND VERSION
5. Follow steps 1-4, with one change to step 4.
6. Place both hands in water before touching the plates.
7. Once again, have a human volunteer touch both plates with their wet hands.

Placing your hands on the metal plates causes the effect of a battery charge. Your hands contain a thin film of sweat that produces a chemical reaction similar to battery acid when placed on the metal plates. Your hands take negatively charged electrons away from the copper plate and transfer them to the aluminum plate, causing it to be negatively charged. The variance in charges between the places produces an electrical current which flows through your body and displays on the meter.

Results For Second Version
In the version where the human’s hands are wet, the reading on the current meter is higher than when the hands are not wet. The human body resists the flow of current through the skin. When wet hands are placed on the plates, the resistance to current is decreased thus increasing the flow of current and creating a higher reading on the meter.