Warning About Electrical Shock

Some of these experiments could produce injury or death. Don't conduct any of these experiments unless qualified to do so. If under 18, proceed only under adult supervision!

The information contained in this website is for general information purposes only. The information is provided by www.sullivan-county.com and I endeavor to keep the information up to date and correct. The experiments presented on this website were conducted in a college classroom under strict instructor supervision. Any reliance you place on such information is therefore strictly at your own risk.

Most of the experiments presented use 5, 12, or 24 volts D.C. and should be safe. For those using over 120 or 220 volts I recommend the following be used in the classroom:

1. Use an isolation transformer. In the case of 220 and higher voltage use a step down transformers to 120 volts.

2. Place a 40 or 25 watt incandescent bulb in series with the experiment. The will limit the current in case of a short. Be extra careful with polarized capacitors because they can explode even under voltage if connected backwards or to A.C.

The primary factor for the severity of electric shock is the electric current which passes through the body, in particular the heart. This current is of course dependent upon the voltage and the resistance of the path it follows through the body. An approximate general framework for shock effects is as follows:

Electric Current
(1 second contact)
Physiological Effect
1 mA
Threshold of feeling, tingling sensation.
10-20 mA
"Can't let go!" current - onset of sustained
muscular contraction.
100-300 mA
Ventricular fibrillation, fatal if continued.

To put this in everyday terms, 1 mA is .001 Amp. A 100 watt light bulb draws 100 watts divided by 120 volt equals .840 Amps or 840 mA. The current from a 25 watt bulb (.208 A 208 mA) can kill you.