Just the highlights.
-
Circa June 1752
-
Ben Franklin never officially wrote up his experiment.
-
The kite had a metal spike on top to discharge the electrical charges in the air.
-
If lightning had struck the kite, the string would be burned or Ben would have been electrocuted by the lightning.
-
He probably flew the kite in the early stages of the storm when he thought he was safe from lightning.
-
The experiment's purpose was to determine what lightning was made of. He determined it was made of electrical charges and not fire. This meant he had a way to postulate how storms behaved. (Although today we are not sure about every part of a storm's life span.)
-
The key was used as an indicator of electricity. It glowed due to corona discharge. It also shocked him.
-
He held onto a dry, 6 inch, silk ribbon to act as an insulator between himself and charges on the key.
-
He flew the kite from indoors or at the very least from a doorway –under dry cover.
-
Do not try Franklin's kite experiment. The odds are very high that you will get struck by lightning and die. A high electrical build up can even occur on a day when there no storms to be seen.
- Much more is discussed in the class notes.
Corona discharge is the glow at the sharp edges of an electrified object. Below are some keys that have been electrified.
![](pics/Corona_Discharge.jpg)
When this glow occurs on the masts of sailing vessels, it is called, "St. Elmo's Fire." More in the class notes.
|