Wilhelm Weber gets the distinction of having the unit of magnetic flux, the weber (Wb), named in his honor. Magnetic flux measures the total magnetic field that passes through a surface. 

(Wondering how to pronounce weber? Hear all about it from one of our researchers.)

The amount of magnetic flux depends on two things: the strength of the magnetic field and the size of the surface area those fields pass through. 

Measurement units are how we quantify stuff. If I say, “Hey, wow, it’s soooo hot today. It feels like 40 degrees Celsius,” the measurement unit is Celsius, and the quantity is 40. 

A monument to Gauss and Weber stands in Göttingen, Germany. Credit: MareikeG/Shutterstock

The whole system of measurement units is commonly known as the metric system (SI). It gives us a standard way to measure length, weight, temperature, and other physical quantities. Virtually every country in the world recognizes the metric system as one of the most important standards ever created.

The metric system is also useful for measuring magnetism. Magnets are the wonderfully mysterious objects that attract (or repel) each other. (That’s also true with people, but that’s a whole different topic.) Magnets are totally fascinating, not to mention useful. 

It turns out that electricity and magnetism are deeply related. In fact, there’s an entire scientific field called electrodynamics that deals with electricity, magnetism, and light. Wilhelm Weber (I’ll call him Willy) was the first to quantitatively describe the relationships among these things. That’s a big deal. 

For example, electromagnetic induction, which is the foundation for electric generators and transformers, is based on a clear understanding of the relationship of electricity and magnetism. 

The measurement of the weber is often accomplished with a device called a fluxmeter. Of course, this isn’t to be confused with the flux capacitor, which enables time travel in Back to the Future (1985). 

Weber and Carl Friedrich Gauss, another notable mathematician and physicist, collaborated on one of the earliest attempts at using electrical wire to send messages, known as the telegraph. There’s a monument to them in Göttingen, Germany.

Carl Friedrich Gauss. Credit: Smithsonian Institution

Gauss made his own contributions to science and mathematics. He described the Gaussian curve while studying random errors’ effects on data. We now know this as the bell curve, or the normal distribution. In the bell curve, most data points tend to cluster in the middle, with fewer outliers on either side (shaped like a bell). This has been used to show data for students’ test performance, people’s heights, and other population-type information. 

Not to be outdone by his friend Willy, Gauss also has a unit of measure named after him. The gauss measures magnetic induction, or how much magnetic field is in an area. 

The Copley Medal

In 1859, Willy was awarded the Copley Medal. It’s described as “the most prestigious and oldest scientific award in the United Kingdom, given annually by the Royal Society of London for outstanding achievements in research in any branch of science.” 

The citation for Weber’s medal reads: “For the investigations contained in his Maasbestimmungen [physical measurements] and other researches in electricity, magnetism, acoustics....” 

The first Copley Medal dates back to 1731; that’s nearly 300 years ago. (All of a sudden, I don’t feel so old.)

Interestingly, Benjamin Franklin received the medal in 1753 (more than a hundred years before Weber got his). Still awarded today, the Copley Medal is considered a precursor to the Nobel Prize, and in fact, many Nobel Prize winners have also received the medal.

Weber’s magnetic career

Born in Wittenberg, Germany, in 1804, Willy was one of 12 children. 

As a physics professor, he was one of the Göttingen Seven—a group of seven professors at the University of Göttingen who were protesting the annulment of the constitution of the Kingdom of Hanover (part of modern Germany) by its new king. 

They refused to sign an oath of allegiance to the king and were “relieved of their posts”—in other words, fired! This affected Weber’s collaboration with Gauss, who was also at Göttingen but was loyal to the king.

Weber’s extraordinary accomplishments with magnetism and electricity remain one of the seminal contributions to understanding the natural world. 

Published Oct. 23, 2024, in the NIST: Taking Measure blog.