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Electrostatic forces

Electrostatic forces make the chair you sit on rigid, the floor you stand on solid, and the water you drink the liquid. The hamburger you consumed for dinner that powers your eyes was made possible by the hay the cow ate. The hay was made possible by photosynthesis from the electromagnetic energy of sunlight. [3] Indeed, electricity is the fundamental controlling agent of all matter, and electrons are a part of the electromagnetic spectrum.

A founding experimenter, Alessandro Volta (1745—1827), was fascinated with electricity and experimented with gas and sparks. As a student he was so interested in this research he wrote a poem in Latin about his experiments. In 1774, Volta became a physics professor and through further experimentation devised the electrophorus. The electrophorus is a simple device that is able to store and discharge static electric charge, and Volta who also discovered methane did many experiments where he ignited gasses with these electric sparks inside glass containers. [4]

Volta was also responsible for early experiments in the creation of batteries and discovered that by dipping the dissimilar metals, silver, zinc, and/or copper, into brine (salty water), he could create a current. Later, he would layer the silver and zinc in cardboard that had been soaked in brine and discovered that he could create a constant current. He called this the voltaic pile, which was the forerunner of the modern battery. [5]

Some contemporary artists have exploited this effect of having dissimilar metals immersed in acidic materials to allow current flow. The artist Norman Tuck, for instance, created a work called Alchemy that used zinc, copper, and salt water to produce a current that causes a pendulum to swing between polar opposites, a kind of prototypical motor.

The contemporary artist Joseph Smolinski uses potatoes as a battery in a work called Potato Cells (2003). In this work, the potato batteries power red LED lights (light emitting diodes, discussed in Chapter 7 more fully) that are embedded in cast resin.

The work helps us to understand that given the proper alchemical mix of materials, batteries can be created from common food including potatoes and lemons. The work is also an elegant reference to the idea of the electromagnetic energy of the sun being stored in the potato cells, to be made available for the powering of the LEDs. [6]


Potato Cells, by Joseph Smolinski. 2003. 


Back to the history of the atom. André Marie Ampère (1775--1836), who was largely a self-educated mathematician, researcher, and a prodigious reader, was rumored to be able to recite L'Encyclopédie verbatim until late into his life. Ampere became a professor of physics and chemistry and is credited as being one of the main discoverers of electromagnetism in 1820, which he named electrodynamics. [7]


Ampere uses the symbol A, which is also referred to as amp or amperage.


Both of these researchers provided insights for James Clerk Maxwell (1831--79), who proved that light is electromagnetic waves that vibrate at ultra-high frequencies. Maxwell would summarize some of the research of Volta, Ampere, and Charles Coulomb. Charles Coulomb (1736--1806) defined early laws of electric charges in saying that:

Like charges repel each other; unlike charges attract.

In other words, if you have two materials with similar electrical charges, they will repel each other, and if you have two materials with dissimilar charges, they will attract each other.

This is why on a dry day when you comb your hair and remove electrons from the strands of your hair, it may stand on end, while your comb now seems to be able to pick up little bits of paper. In this process, your hair now has a deficit of electrons from brushing the electrons into your comb, and the atoms in your hair, which are now mostly positive, are repelled by each other. This gives new meaning to the phrase “I am having a bad hair day”.