A Van de Graaff generator was used to assist in the creation of the spark seen in this photograph. It works by creating an excess of electrons on its metal sphere. The electrons always seek the path of least resistance to the ground. In this case, our subject on the left has contact with the Van de Graaff generator, but is standing on a wooden platform while extending his finger to our other subject on the right. Since the wooden platform on which he is standing is an insulator, the easier path for the electrons to be grounded is not through the body of our first subject, but through the body of our second subject. The electrons utilized the air between the two fingers when they were at the right distance, to complete the circuit. This created a current that led to the ground. The spark of white light visible in the photograph is the current being discharged between the fingers and finally to the ground.

Alyssa Terminesi
St. Elizabeth Catholic High School, Thornhill, Ontario
2nd Prize ( High School Individual Category )
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