This is video tutorial of building of conductivity tester for different materials
- Thick copper wire
- AA size dry cell 2
- Scotch Tape
- Rubber Band
- Sand Paper
For construction steps watch Video.
Science of Conductivity Tester
A conductivity tester consist of two AA size dry cells connected in series, LED and two electrdes.
If sample is a good conductor, some amount of current will pass trhrough the LED and it will light , Its better to insert resistance of 300 ohm to protect the LED from over current.