“Put your hand on a hot stove for a minute, and it seems like an hour. Sit with a pretty girl for an hour, and it seems like a minute. THAT’S relativity,” said Albert Einstein, while he was attempting to describe his iconic, yet still-baffling, Theory of Relativity to feebler minds. While many believe that it was this highly complex theory, which won him the Nobel Prize, Einstein was bestowed with the highest honor in science for an entirely different and much more practical endeavor.
The Nobel Prize was given to Albert Einstein in 1921 for his outstanding contribution to the field of physics. He received it primarily for his explanation of the photoelectric effect. The confusion about the actual topic may be justified due to the fact that Albert Einstein had managed to gain exceptional understanding of physics as well as the universe in a single year. Oddly enough, it took a lot of convincing and more than 16 years for Einstein to get the coveted award.
What earned Albert Einstein a Nobel in physics? By the turn of the 20th century, physicists were well aware that, in some circumstances, exposing certain materials to light could create an electric current. In fact, in the late 19th century, an American named Charles Fritts had even created a working solar cell from selenium.
However, observing that light can create electricity is not the same as understanding why light can create electricity. It was widely understood and accepted that light worked as a wave. But a wave can’t create electricity. Simply put, a wave of light just wouldn’t have enough energy to cause materials like selenium to shoot off electrons as fast as they did, when exposed to light.
A young Einstein, at mere 26-years-old, suggested that perhaps light wasn’t a wave. He justified that light could very well create electricity, if it behaved like a particle rather than a wave, on some occasions.
“Phenomena like the photoelectric effect are more readily understood if one assumes that the energy of light is discontinuously distributed in space. In accordance with the assumption to be considered here, the energy of a light ray spreading out from a point source is not continuously distributed over an increasing space but consists of a finite number of energy quanta which are localized at points in space, which move without dividing, and which can only be produced and absorbed as complete units.”
Although only a brief paragraph in his research paper published in 1905, covered the photoelectric effect, it outlined how a light particle might deliver enough energy, all at once, to knock an electron off an atom and create an electric current. As a natural succession, within a short decade, Robert Millikan had experimentally verified the equation.
Essentially, the idea that Einstein described in 1905 — that won the Nobel Prize a decade and half later — is what makes today’s solar panels work.
[Image credit | Rare Historic Photos, Solar Panels]