Science Buddies: "Ask an Expert"

Hello, I just got the ok from my teacher to do this project, but there is one problem, i don't understand your instructions on how to build the apparatus
ex."We moved the positive electrode when changing the gap distance between the conducting spheres. The straight edge of the protractor was used as a ruler because it was a handy size for the experiment."
the thing is move where?

Thank you for your consideration.

geekyazn - The instructions in the described experiment are pretty clear. The two electrodes (spheres) are placed in the 'V' of the insulating cardboard. It doesn't really matter which sphere you move, the idea is to start with a small gap and achieve a spark between the two spheres. Keep increasing the space until you fail to get a spark. The distance that is measured between the spheres where a spark is still achieved is the distance you use in calculating the voltage output of the igniter. Using the value of 3,000 volts / millimeter in dry air, if your distance was 2 mm, the voltage developed is 6,000 volts. If it was 3 mm, the voltage is 9,000 volts. Placing different insulating or conducting materials between the spheres will lead you to other conclusions about dielectric (insulating) properties of various materials.

https://www.sciencebuddies.org/science- ... p032.shtml

Rick Marz