Visible Light for Dummies - The Freelance Files MMCCXXIII

cartoon of photons

A not-so-surprising number of our nominees for DotD are caught by our staffers because of errors in common sense. Take, for instance, the ignoramus who thought a normal human could operate a stationary bicycle at 500 RPM... Ignorance of the topic should be no excuse, but hey: when some website offers to pay you fifteen bucks for 300 words of bullshit, why not pump out as many posts as possible? Whatever the case, much of what we've found at the supposedly more technical websites (Leaf Group's Sciencing.com or WiseGEEK's AlltheScience.com, for instance) has been at least somewhat suspect because of an author's weak comprehension of the topic. You know, like Bill Richards when he tried to explain "How to Convert Photons to Joules" for Sciencing.com.

As befits a J-school grad, Richards deserves props for finding a useful reference at a site called TechTarget.com. It's what he did with the information there that raised the collective hackles of the staff at the nomination meeting. Take, for instance, the strange wording of his first sentence:

"A photon is a singular [sic] particle of light."

That's Bill's attempt to dodge plagiarism charges by rewording "fundamental particle" from his source. His problem, of course, is that singular means neither "fundamental" nor "single."¹ Truth be told, that's what caught someone's eye in our shop. Some of Richards' other foul-ups, all of which can probably be attributed to scientific ignorance (or simple laziness) include the following:

• "...the speed of the photon..." – Again, plagiarism avoidance: it's not "speed," it's velocity. Although liberal arts grads may not know this, speed and velocity are different.
• "Hz is the same as 1/seconds..." – Hertz is the unit of frequency in cycles per second. What "1/seconds" is supposed to mean is beyond us.
• "...the electromagnetic wavelength, in meters, of the photon..." – Strictly speaking, the photon doesn't have a wavelength; the wave containing the photon has a wavelength. Oh, and it's not an "electromagnetic wavelength," it's just a wavelength.
• "...where the wavelength is 10 m..." – Bill wandered away from his discussion of light here. Visible light has wavelengths in the nanometer range, on the order of 10^-7 meters. Waves with 10-meter length are radio waves. We guess Bill missed that information while taking introduction to film.
• "In the example, we multiply by 12 photons..." – does Bill have the slightest idea how insignificant a quantity of "12 photons" might be?

No, our Dumbass of the Day did a good job of finding an authoritative source for the information. Sadly, he didn't understand it well enough to reword it; hence his award... especially since we're pretty certain Bill had no idea what the word "joule" means.

¹ A popular online dictionary defines singular as "exceptionally good or great; remarkable..."

SI - PHYSICS