Question
Fri May 25, 2012 By:
 

explain the benjamin franklins kite experiment once again?

Expert Reply
Fri May 25, 2012

The idea was to fly the kite into the storm clouds and conduct electricity down the kite string. A key was then attached near the bottom, to conduct the electricity and create a charge.

The kite was struck by lightning and, when Franklin moved his hand towards the key, a spark jumped across and he felt a shock, proving that lightning was electrical in nature.

the 46 year-old Ben Franklin decided to fly a kite. With the help of his son, William, they attached his kite to a silk string, tying an iron key at the other end. Next, they tied a thin metal wire from the key and inserted the wire into a Leyden jar, a container for storing an electrical charge. Finally, as the sky darkened and a thunderstorm approached, they attached a silk ribbon to the key. Holding onto the kite by the silk ribbon, Ben flew the kite and once it was aloft, he retreated into a barn so that he would not get wet. The thunder storm cloud passed over Franklin's kite, whereupon the negative charges in the cloud passed onto his kite, down the wet silk string, to the key, and into the jar. Ben however, was unaffected by the negative charges because he was holding the dry silk ribbon, insulating him from the charges on the key. When he moved his free hand near the iron key, he received a shock. 

Because the negative charges in the key were so strongly attracted to the positive charges in his body, a spark jumped from the key to his hand. Franklin's experiment successfully showed that lightning was static electricity. You can experience this same reaction when you shuffle your feet on a carpet and reach for a metal doorknob.
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