Education

The Shocking Truth About Electricity: 5 Fascinating Facts

Learn 5 surprising facts about electricity that correct misconceptions, from electron speed to the most powerful electric eel ever recorded.

By Written Facts StaffJune 3, 2023Updated October 8, 20267 min read

You flip a light switch and the room lights up straight away, so it's natural to picture electricity rushing through the wire. It doesn't. The electrons in that wire move more slowly than a snail. That is the first of five facts below that correct things most of us were taught. The others: lightning strikes less often than the old figure says. Benjamin Franklin was not the first person to prove that lightning is electricity. The first battery was modeled on a fish. And the strongest electric animal ever recorded was named after the man who built that battery.

1. The electrons in your wires barely move

When a current flows through a copper wire, each free electron does move fast, at speeds on the order of a million meters per second. But it moves in random directions. The current only adds a small shared "drift" on top of that random motion, and for ordinary currents the drift is on the order of millimeters per second. In one worked example from Georgia State University's HyperPhysics, a copper wire carrying 3 amperes has a drift velocity of 0.00028 meters per second. At that pace an electron would take about an hour to travel one meter.

So why does the light come on instantly? The electrons don't have to make the trip from the switch to the bulb. The wire is already full of them. Closing the switch sets up an electric field along the whole circuit, and that field pushes electrons everywhere in the wire at almost the same moment. The signal travels at a speed on the order of the speed of light, about 300 million meters per second, even though each electron is barely moving.

2. Lightning strikes about 44 times a second, not 100

Electricity in the sky works on the same basic principle as the spark you get from a doorknob. NOAA calls lightning "a gigantic spark of static electricity," the same kind that sometimes shocks you when you touch a doorknob. It also admits that scientists still don't fully understand how lightning works.

Many articles still say lightning hits the Earth 100 times a second. That number is an estimate from 1925. Satellite measurements have since replaced it. NASA and Japan's space agency began watching lightning from orbit with the Lightning Imaging Sensor, launched in 1997. Since 2017, NOAA's GOES-R weather satellites have carried Geostationary Lightning Mappers that watch half the planet at once. Based on that kind of data, NOAA puts the rate at about 40 flashes per second. Other high-quality data gives an average of 44 (give or take 5) per second, or about 1.4 billion flashes a year.

Lightning is not spread evenly. The most electric spot on Earth is Lake Maracaibo in Venezuela. There, Catatumbo lightning can flash several times a minute on up to 300 nights a year, and the area gets about 250 flashes per square kilometer each year.

3. Franklin proposed the lightning test, but someone else did it first

We know lightning is electrical because of an experiment from 1752. It is usually credited to Benjamin Franklin and his kite, but the full story is more interesting.

In 1750, Franklin publicly suggested a way to prove that thunderclouds carry electricity. He proposed putting a "Sentry Box," big enough to hold a man, on top of a tower, with an insulated iron rod reaching 20 to 30 feet into the air. French naturalist Thomas-François Dalibard translated Franklin's writings into French and published them in Paris in early 1752. He then set up the experiment himself. On May 10, 1752, at Marly-la-Ville, a retired French dragoon working from Dalibard's instructions drew sparks from a tall insulated iron rod during a storm. That was the first successful proof that lightning is an electrical discharge.

Franklin did his kite experiment near Philadelphia in June 1752, before news of the French success reached him. He tied a key to the kite's string, which carried the charge down, and used a silk ribbon to insulate it from the ground. So the idea was Franklin's, but the first proof came from France.

The danger was real. On August 6, 1753, scientist Georg Wilhelm Richmann was killed in St. Petersburg while experimenting with an insulated rod near a storm. His death was reported around the world, and critics used it to stir up public opposition to lightning rods. Franklin kept improving his lightning rods anyway. His 1762 design called for steel rods 5 to 6 feet long with sharp points, a continuous conductor running down the outside of the building, and a grounding rod driven 10 to 12 feet into the earth.

4. The first battery was copied from a fish

The battery came out of a scientific argument. Luigi Galvani believed living things produced their own "animal electricity." Alessandro Volta disagreed. He thought the electricity came from the metals Galvani was using.

Volta's breakthrough was inspired by a fish. He read a paper by the English chemist William Nicholson about the torpedo, an electric ray famous since ancient times for its strong shocks. Nicholson described its electric organ as being made of hundreds of thin columns, and he speculated that a machine could copy it. The fish's electric organ is built from stacks of cells that look a lot like a roll of coins. So Volta cut coin-shaped discs, stacked them in different orders, and found an arrangement that worked: copper and zinc discs in pairs, with paper soaked in saltwater between each pair.

On March 20, 1800, Volta described the device in a letter to Sir Joseph Banks, president of the Royal Society of London. He called it an "artificial electric organ." We now call it the voltaic pile, the first electric battery. Volta later demonstrated it to Napoleon Bonaparte, and he even suggested dressing it up "like an electric eel" to impress audiences.

5. The record for animal electricity belongs to an eel named after Volta

That brings us to electric eels. Despite the name, they are fish, not true eels. For about 250 years, scientists thought there was only one species. In a study published in Nature Communications on September 10, 2019, a team led by Smithsonian zoologist David de Santana examined 107 specimens from across the Amazon region. Using physical comparisons and genetic analysis, they found three species.

One of the new species was named Electrophorus voltai after Alessandro Volta. It produced a discharge of 860 volts, the highest voltage ever recorded from an animal. The previous record was 650 volts. Volta built the first battery by copying an electric fish, and more than two centuries later, the most powerful electric fish known was named after him.

The 2019 study also pointed out how much of the Amazon's wildlife is still undiscovered. Cornell neurobiologist Carl Hopkins said the differences between the species are subtle, and that sampling more widely might turn up even more.

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