Kite experiment
Encyclopedia
The kite experiment was a scientific experiment proposed and later conducted by Benjamin Franklin
with assistance from his son William Franklin
. The experiment's purpose was to uncover then unknown facts about the nature of lightning
and electricity
.
, a rudimentary electrical battery
. The experiment was supposed to be executed on the top of the spire on Christ Church in Philadelphia. Franklin conducted the experiment in June 1752. By this time, he had realized the dangers of using conductive rods and instead used a kite
because the increased height allowed him to stay on the ground and because the kite was safer. Franklin kept the string of the kite dry at his end to insulate him while the rest of the string was allowed to get wet in the rain to provide conductivity. A key was attached to the string and connected to a Leyden jar
, which Franklin correctly assumed to accumulate electricity from the lightning bolt. The kite wasn't struck by visible lightning, but Franklin noticed the strings of the kite were repelling each other and deduced that the Leyden jar was being charged. Franklin reportedly received a mild shock by moving his hand near the key afterwards, because as he had estimated, lightning had negatively charged the key and the Leyden jar, proving the electric nature of lightning.
Fearing that the test would fail or that he would be ridiculed, Franklin took only his son to witness the experiment with himself and published the accounts of the test in third person.
may be positive or negative. The experiment helped Franklin in the creation of some of his later inventions, like the lightning rod
. The experiment also garnered attention and many attempted to recreate it. Some of the experimenters are known to have died during recreating the experiment.
The kite experiment remains one of the best known scientific experiments today, to the point of being surrounded by myths and legends of varying accuracy. For example, most artistic renditions of the kite experiment portray Franklin's son as a child, while in actuality he was an adult by then.
Benjamin Franklin
Dr. Benjamin Franklin was one of the Founding Fathers of the United States. A noted polymath, Franklin was a leading author, printer, political theorist, politician, postmaster, scientist, musician, inventor, satirist, civic activist, statesman, and diplomat...
with assistance from his son William Franklin
William Franklin
William Franklin was an American soldier and colonial administrator. He served as the last Colonial Governor of New Jersey. Franklin was a steadfast Loyalist throughout the American War of Independence, despite his father Benjamin Franklin's role as one of the most prominent Patriots during the...
. The experiment's purpose was to uncover then unknown facts about the nature of lightning
Lightning
Lightning is an atmospheric electrostatic discharge accompanied by thunder, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms...
and electricity
Electricity
Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...
.
Experiment
In 1750, Franklin proposed an experiment with conductive rods being used to attract lightning to a Leyden jarLeyden jar
A Leyden jar, or Leiden jar, is a device that "stores" static electricity between two electrodes on the inside and outside of a jar. It was invented independently by German cleric Ewald Georg von Kleist on 11 October 1745 and by Dutch scientist Pieter van Musschenbroek of Leiden in 1745–1746. The...
, a rudimentary electrical battery
Battery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...
. The experiment was supposed to be executed on the top of the spire on Christ Church in Philadelphia. Franklin conducted the experiment in June 1752. By this time, he had realized the dangers of using conductive rods and instead used a kite
Kite
A kite is a tethered aircraft. The necessary lift that makes the kite wing fly is generated when air flows over and under the kite's wing, producing low pressure above the wing and high pressure below it. This deflection also generates horizontal drag along the direction of the wind...
because the increased height allowed him to stay on the ground and because the kite was safer. Franklin kept the string of the kite dry at his end to insulate him while the rest of the string was allowed to get wet in the rain to provide conductivity. A key was attached to the string and connected to a Leyden jar
Leyden jar
A Leyden jar, or Leiden jar, is a device that "stores" static electricity between two electrodes on the inside and outside of a jar. It was invented independently by German cleric Ewald Georg von Kleist on 11 October 1745 and by Dutch scientist Pieter van Musschenbroek of Leiden in 1745–1746. The...
, which Franklin correctly assumed to accumulate electricity from the lightning bolt. The kite wasn't struck by visible lightning, but Franklin noticed the strings of the kite were repelling each other and deduced that the Leyden jar was being charged. Franklin reportedly received a mild shock by moving his hand near the key afterwards, because as he had estimated, lightning had negatively charged the key and the Leyden jar, proving the electric nature of lightning.
Fearing that the test would fail or that he would be ridiculed, Franklin took only his son to witness the experiment with himself and published the accounts of the test in third person.
Aftermath and legacy
Franklin's experiment was successful, and helped him ascertain that lightning is a form of electricity. Franklin also found out that electric chargeElectric charge
Electric charge is a physical property of matter that causes it to experience a force when near other electrically charged matter. Electric charge comes in two types, called positive and negative. Two positively charged substances, or objects, experience a mutual repulsive force, as do two...
may be positive or negative. The experiment helped Franklin in the creation of some of his later inventions, like the lightning rod
Lightning rod
A lightning rod or lightning conductor is a metal rod or conductor mounted on top of a building and electrically connected to the ground through a wire, to protect the building in the event of lightning...
. The experiment also garnered attention and many attempted to recreate it. Some of the experimenters are known to have died during recreating the experiment.
The kite experiment remains one of the best known scientific experiments today, to the point of being surrounded by myths and legends of varying accuracy. For example, most artistic renditions of the kite experiment portray Franklin's son as a child, while in actuality he was an adult by then.