Jean Charles Athanase Peltier electromagnetism |
Peltier effect
Jean Charles Athanase Peltier put a battery on a Seebeck circuit, that is, an electric circuit having a junction of dissimilar metals, and found that one side of the junction heated up and the other side cooled.
Findings
William Gilbert found that the earth was a giant magnet. Robert Boyle found that electrical attraction would span a vacuum. Ewald Georg von Kleist and Pieter van Musschenbroek found a way to store electricity in jars. Benjamin Franklin found the difference between positive and negative electric charges. Charles Augustin de Coulomb found that attraction of charged objects depends on the amount of charge and the distance between them. Alessandro Volta invented a battery to produce electricity. Seebeck found the Seebeck effect—a temperature difference across different metals in a circuit created a magnetic field. André-Marie Ampère found that two parallel wires carrying electric currents attract or repel each other depending on the direction of the flow. Hans Christian Ørsted found a current created a magnetic field. Ohm found the voltage across a conductor divided by the current equals the resistance.
Electrical units
The ampere or amp the unit of current honors André-Marie Ampère who discovered the relation The coulomb the unit of charge honors Charles-Augustin de Coulomb who developed the law of electrostatic force of attraction and repulsion. The farad the unit of capacitance honors Michael Faraday who discovered electromagnetic induction. The gauss the unit of magnetic field strength honors Carl Friedrich Gauss who related magnetism to mass, charge, and time. The hertz the unit of frequency honors Heinrich Hertz who proved the existence of electromagnetic waves The henry the unit of inductance honors Joseph Henry who discovered electromagnetic induction about the same time as Michael Faraday. The joule the unit of energy honors James Prescott Joule who discovered the relationship between heat and mechanical work. The ohm the unit of resistance honors Georg Ohm who discovered Ohm’s law. The tesla the unit of magnetic flux density honors Nikola Tesla who helped develop alternating current. The volt the unit of voltage honors Alessandro Volta who invented the electric battery. The watt the unit of power honors James Watt who improved the steam engine. The weber the unit of magnetic flux honors Wilhelm Eduard Weber who worked with Hertz and developed a system of measurements for electric currents.
Solid-state effects
The transistor was invented five years before I was born followed by the transistor radio when I was two. I found out about solid-state heating and cooling and solid-state generation of electricity when I was in the ninth grade. I had read a lot of science fiction. Solid-state effects revealed new dimensions. Secretly it seemed as though a nine-volt battery could open an invisible world to benefit mankind. The next step should have been antigravity devices, curing cancer, and ending war. The mind can transcend the mediocre and destructive to span the universe but not without corresponding effects.
As an adult I know that technology cannot by itself solve the world’s problems, at least not without years and years of effort that also addresses cultural and psychological realities.
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