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Using his AC current generator, what device did Tesla build that could take low frequencies and step them up to extremely high frequencies?

The Tesla coil

In 1891, Tesla patented a device known as the Tesla coil that took ordinary household current of sixty cycles per second and increased it to extremely high frequencies, to the hundreds of thousands cycles per second.

Tesla considered this invention to be his greatest. He used it to conduct innovative experiments in lighting, phosphorescence, x-ray generation, electrotherapy, and the transmission of electrical energy without wires.

Tesla's research brought him into the invention of wireless communication. Who is often credited with the invention of radio?

Guglielmo Marconi

Working with his newly created coils, Tesla discovered he could transmit and receive powerful radio signals when they were tuned to resonate at the same frequency.

When a coil is tuned to the signal of a particular frequency, it magnifies the incoming electrical energy through resonant action.

Tesla applied for several basic radio patents in 1897 and was granted them in 1900. At the same time an Italian experimenter, Guglielmo Marconi was also working with his own device for wireless telegraphy. When he applied for patents in the United States he was turned down repeatedly because of the priority of Tesla’s patents.

Marconi used some of Tesla’s wireless ideas and on December 12, 1901, Marconi was able to transmit and receive signals across the Atlantic Ocean. When asked about Marconi’s achievement, Tesla commented, “Let him continue. He is using 17 of my patents.”

Yet in 1904, the U.S. Patent Office suddenly reversed its decisions and granted Marconi the patent for the invention of radio.

In 1909, Marconi won the Nobel Prize for Physics in recognition of his work in the development of wireless telegraphy. Tesla was furious and sued for copyright infringement. It wasn’t until 1943 that the U.S. Supreme Court finally reversed the decision and awarded Tesla the patent for radio. Unfortunately, Tesla was no longer alive, having died a few months previously.

Successful inventors need financial backing. Tesla teamed with George Westinghouse on the hydroelectric power plant at Niagara Falls. At the end of the 19th century, another prominent New York financier agreed to lend Tesla money to build an extensive laboratory on Long Island. Who was it?

J.P. Morgan

Tesla’s lifelong obsession was the wireless transmission of energy. In 1900, J.P. Morgan invested in a new laboratory on Long Island, N.Y. called Wardenclyffe. The site, designed by the prominent architect Stanford White, was to be a small city with houses, stores, and buildings to house 2,500 workers.

The centerpiece of the lab was to be a tower that could transmit messages, news, stock reports, weather warnings, and personal messages across the ocean wirelessly. The Wardenclyffe Tower began 120 feet below ground, rose 187 feet above ground, and was to be capped with a 55 ton sphere of steel.

Tesla experimented there for only a few days before creditors began to confiscate equipment for non-payment of debts. The tower was never finished and was completely destroyed in 1917 when the US government suspected German spies might use it to relay military messages during the First World War.

This investment was considered to be one of JP Morgan’s failures and Tesla’s greatest defeat.

In 1960, The Grand Conference on Weights and Measures dedicated the term “tesla” as a unit of measure. What does a tesla measure?

Magnetic field strength

The earth itself is a magnet that can generate electricity utilizing frequencies as a transmitter. All that is needed on the other end is a receiver.

In 1888, Tesla realized that he could rotate a magnetic field if two coils at right angles are supplied with AC current 90° out of phase. This was a fundamental discovery in physics. It helped create the field of magnetic resonance imaging (MRI). MRIs are a powerful diagnostic tool in medical imaging.

Radio signals can be elicited from the atoms in soft tissue when exposed to an electromagnetic field. These signals are transmitted and used to construct a computerized image of the interior of the body. The higher the signal, the higher the quality of the image.

The strength of the magnetic field is measure in gauss (G) or tesla (T) units.
1 Tesla = 10,000 Gauss

How many Nobel Prizes did Nikola Tesla win?

He won the same amount as Thomas Edison. Zero.

Tesla thought that everything we need to understand the universe is around us at all times. He believed in harnessing the forces of nature to human needs. He was green.

He anticipated worldwide wireless communication. He was visionary.

Tesla made a great deal of money on his patents but then spent even more on his experiments. He died penniless. He was not a businessman.

Tesla had keen memory and the ability to visualize and construct complicated objects in his mind’s eye. He thought long and hard before physically assembling them. He believed he might be the hardest-working man if thought is equivalent to labor.

He was a genius.

Atoms are formed from electrons, protons, and neutrons. Which two types of particles form the atomic nucleus?

Protons and neutrons

Electrons are placed at a distance, outside the nucleus.

All elements are made up of atoms. Atoms are the smallest indivisible unit of an element. Atoms are made up of protons, electrons, and neutrons.

Protons have a positive electrical charge (+), electrons have a negative electrical charge (-), and neutrons are neutral (0) with no electrical charge.

Protons and neutrons cluster to form a densely packed core of positive charge, the nucleus of the atom.
Unlike charges (+ and -) attract each other. Like charges (+ and +, - and -) repel each other. Atoms, in their elemental form, have a balanced amount of positive protons and negative electrons.

Which particle is necessary for the formation and breakdown of chemical bonds?


An atom is mostly empty space.

The nucleus is a densely packed core of positive charge. Negatively charged electrons are in constant movement outside and around the atomic nucleus. It is the attraction of opposite charges that bind the atom together.

Electrons with the least amount of energy are closest to the nucleus and those with a greater amount of energy are further away.

Atoms can share acquire, lose, or share electrons with other atoms. This action results in chemical bonds  that hold atoms together to form molecules. Reactions generally bring reactants to a more stable state.

What do we call the flow of electrons between atoms?


When the charges are out of balance, an atom is either positively or negatively charged. The switch between one type of charge to another allows electrons to flow from atom to atom. This flow of electrons is what we call electricity.

Everything in the universe is made up of atoms.

In our body, neural signals are electrical in nature. Electrical signals within the human body are fast. They allow for nearly instantaneous response to control messages.

What do we call the type of electricity that has an imbalance of electrical charges within or on the surface of a material?

Static electricity

Some atoms hold onto their electrons more tightly than others.  Certain materials will “capture” electrons when they come into contact with other matter. When separated, a charge imbalance may occur. Electrons have built up on one surface and will remain there until they are discharged or moved.

Since the charges are identical, the electrons repel each other and try to separate.

Because this electricty does not flow through wires or conductor that transmit energy, it is called static.

When an atom gains an electron, is it more positively or negatively charged?


An electron is a subatomic particle with a negative charge. An atom acquiring an electron would increase in negative charge and decrease in positive charge.

The addition of electrons is called reduction because the negative charge has reduced the amount of positive charge.

The loss of electrons from a substance is called “oxidation” because the positive charge is increased.

When an electron moves from one molecule to another, is it considered an oxidative reaction or a reduced reaction?


When an electron moves from one molecule to another, one molecule loses an electron and other gains an electron. You cannot have one without the other. Reduction and oxidation occur simultaneously. Hence is it shorted to “redox” reaction.

Not all redox reactions involve the complete transfer of electrons. It is still considered a redox reaction when substances share electrons because positive and negative charges have shifted.

No chemical bonds are broken in redox reactions but changes take place in the molecular structure of the molecules and the molecules nearby. This shape shift enables electrons to move between molecules.

Many biological processes rely on redox reactions. The relocation of electrons releases energy stored in organic molecules. This energy is ultimately used to synthesize ATP.

How fast does an electron move in a wire?

Quite slowly

An electron, if pushed, can travel nearly the speed of light in open space like in outer space or in an accelerator.

Traveling through matter, in this case a wire, slows it down to snail’s pace. For electron to move down a wire, it interacts with many atoms along the way. They kind of drift, moving at about 1 meter per hour. 

While electrons travel slowly within a wire, their interaction propagates into a wave. The exact length of time it takes for an electromagnetic field to travel in wire depends on the type and thickness of the wire but it can travel nearly the speed of light.

Why are wires usually made of metal?

Metals are conductors

The physical and chemical behavior of an atom is determined by its outermost electrons. Metals readily lose electrons in their outermost shell.

Wire, being made of metal, is an excellent conductor as these electrons flow freely from particle to particle with little resistance.

Yet as electrons flow in a wire, they collide with the metal atoms and move them faster. This friction produces heat. The faster the atoms move, the hotter the wire gets.    

Your toaster is a good everyday example of electrons making heat. Metals, conductors, and electrons all help to make your morning breakfast.

If electrons pass freely through conductors, what do we call those materials that resist the flow of electrons?


The difference between conductors and insulators is how strongly the electrons are held in the chemical bonds to the atom.

Electrons move easily through metals. Non-metal elements hold their electrons more tightly in chemical bonds and resist the motion of charge through them.

Plastics make good insulators because they have few or no free electrons. Copper wires are coated with insulating material to prevent the charge from spilling out.

With enough voltage applied, however, any insulating material will break down and start to leak electrons.  This is often a dangerous short-circuit spark.

As in a wire, electrons move through our bodies generating energy. What is the name of the series of compounds through which electrons move and create chemical energy in the form of ATP?

Electron transport chain

The electron transport chain is a series of redox active compounds found on the inner membrane in mitochondria and in the thylakoid membrane in choloroplasts.

Electrons pass sequentially through the chain, meeting compounds with increasing affinities for electrons until they are finally transferred to oxygen, the ultimate oxidant.

As they pass, they electrically and chemically charge the membrane.  This charge is used to drive synthesis of ATP, stored chemical energy for cell survival and growth.

It is how plants extract energy from sunlight and animals extract energy from food.

This week's answer:

In 1966, a seminal paper on how electrons transfer in biology was published the Biophysical Journal. Who co-authored the paper? Hint: he had very close ties to the Department.

Britton Chance

Britton Chance and Don DeVault co-authored a paper “Studies of Photosynthesis using a Pulsed Laser” in the Biophysical Journal.

In it, they describe that electrons don’t pass from molecule to molecule by collisional contact, but instead quantum mechanically “tunnel”  through the molecular space in the proteins.

Biological electron tunneling can take place even near absolute zero of temperature where nearly all molecular motion has stopped.


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Past questions and answers are in the trivia archives: 2012 / 2013

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