Sunday, April 24, 2016

Reflection and Mirrors for Dummies

Reflected light vs. refracted light
Reflection vs. refraction
If you've been paying attention at all in the past decade or two, you know that the education system in the USA has been turning out far too many people who are highly literate in pop culture but know squat about science, technology, engineering and math: the STEM subjects. Even if you haven't been paying attention, all you'd have to do is look at the sort of bullpuckey answers published at eHow.com by journalism, English literature and political science graduates when the question is even the slightest bit "science-y." Wanna see what we mean? Check out the mess eHow.com's Jack Ori (aka Stephanie Silberstein) made when trying to answer the simple question "What Makes Light Reflect Off of  Mirrors?" at Sciencing.com.

Jack – according to LinkedIn, the holder of an MFA in creative writing – did get creative in his post. Oh, he got the basic bits and pieces right:
  • Light is energy.
  • The brain translates light to images.
  • A "mirror... reflects light more perfectly than ordinary objects..."
  • The images produced by planar, convex and concave mirrors are different.
     All of which left us with an important question for Ori. You see, Jack opined that
"A mirror is a surface that reflects light more perfectly than ordinary objects. Most objects reflect light at varying angles. This is more accurately called refraction, because the rays of light bend when they hit the object and move off in varying directions. This allows us to see the object they bounced off of."
Jack's ignorance of optics and physics (presumably an outgrowth of an educational pathway that avoided science classes) leaves him with some problems there:
  1. The original questioner asked, "What makes light reflect off of mirrors?" Ori didn't answer the question!
  2. No, Jack, reflection is NOT "more accurately called refraction"!
  3. Refracted light does NOT "hit the object and move off in varying directions": any substance that refracts light has a specific index of refraction, so light always bends by the same angle.
  4. Some vaunted content editor at eHow actually let Ori publish "bounced off of"? Shame!
For the record, mirrors work not because the glass reflects light (as Jack implies) but because the back side of the glass is coated with a thin layer of silver, and silver reflects light nearly perfectly. If you read Ori's entire post, however, you don't see the word "silver" at all. So Jack fails to answer the original question while throwing a lot of half-baked, misinformed science at the page. That makes Jack the perfect candidate for the Antisocial Network's Dumbass of the Day award; his/her third (and counting)     
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