BEN FRANKLIN’S KITE WAS STRUCK BY LIGHTNING? (William J. Beaty)

Never happened! Many people believe that Ben Franklin’s kite was hit by a lightning bolt, and this was how he proved that lightning was electrical. A number of books and even some encyclopedias say the same thing. They are wrong. When lightning strikes a kite, the spreading electric currents in the ground can kill anyone standing nearby, to say nothing of the person holding the string! So what did Franklin actually do? He showed that a kite would collect a tiny bit of electric charge out of the sky during a thunderstorm. Electric leakage through the air caused his kite and string to become electrified and so the hairs on the twine stood outwards. Twine is slightly conductive, so the imbalanced charge spread to all parts of the kite string. Franklin used the twine to electrify a metal key, and tiny sparks could then be drawn from the key. (He used a metal object because sparks cannot be directly drawn from the twine, it’s not conductive enough.) This suggested that some stormclouds carry strong electrical net-charge. It IMPLIED that lightning was just a large electric spark. The common belief that Franklin easily survived a lightning strike is not just wrong, it is dangerous: it may convince kids that it’s OK to duplicate the kite experiment as long as they “protect” themselves by holding a silk ribbon. Make no mistake, Franklin’s experiment was extremely dangerous, and if lightning had actually hit his kite, he certainly would have been killed.

About Rob W Harrison
There is a part of my mind that stubbornly thinks about science. I have a life, job, wife and family but without my Van Der Graaf Generator life would be incomplete. I am a great believer that this amazing universe came into being through process: movement >pressure > density > mass. Maybe I believe in an non viscous ether. Anyway this is where I can share my thoughts.

6 Responses to BEN FRANKLIN’S KITE WAS STRUCK BY LIGHTNING? (William J. Beaty)

  1. Any idea what metal the key was made of?

  2. rhonda says:

    this is totaly wrong. plus he didnt use twine he used carbonated cotton! duh

    • From Franklin’s description, the kite was made of silk, and the string was made of hemp. Franklin stood in a dry shed so he wouldn’t get wet, so he was not non-conductive.
      The key was really a capacitor. My theory is the reason so many people have died recreating this experiment is 1.) they stood in the storm and got wet 2.) Their kite (key) actually did get hit by lightning instead of just absorbing some charge. I agree with the author that Franklin’s kite did not get hit by lightning, nor did it need to have been to absorb some charge.

      • jewlry says:

        he is not non -conductive your body is a conductor no matter how dry or wet you are. you will still get struck by lightning . I do not think he still survive that accident 100 million people get struck each day and do not survive. so what made him so special i think he use rubber gloves on him or his whole body was covered with rubber and when he felt a little shock people over exaggerated and said he still survive. think about this whoever reads this.

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