Units Matter

A news item popped up today about how alcohol conglomerate Diageo would be offering nutritional information. However, a little bit of cognitive dissonance set in after reading this sentence “And a 12 oz serving of Guinness — often referred to as a meal in a glass for good reason — clocks in at an eye-opening 678 calories.

Wait – what? Guinness cans already have nutritional information, and they certainly don’t read 678 calories!

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Frosty, the car window

Sometimes frost on the *inside* surface of the car’s windows is a fact of life here at the primary testing facility. The defroster grid in the back window, while typically used to melt frost, the conditions were such that they became nucleation sites for the frost on the inside surface instead!



Consensus online is that this problem is related to excess moisture in the cabin, which considering our area has had somewhere between 157.5226 ” this season (70″ difference? yup, that bugs me), tracked in snow and wet carpets is a likely culprit.

Fun with band-aids

Unlike our previous posts, this is simply a fun observation. I knew about the wintergreen-life-savers-in-the-dark trick, but I learned this morning that pulling open a band-aid wrapper produces a beautiful bluish glow for similar reasons. This lovely light production is due to triboluminescence, and I likely only noticed because I was too lazy to turn on the bathroom light this morning.

The blue color is due to excited nitrogen in the air. In theory, opening a band-aid wrapper should produce a different color if you could open a band-aid under an atmosphere with a different dominant gas. The air we breathe is 78% Nitrogen, which is why the glow is due to that gas, but if we could change the proportions to have a different dominant gas, other colors might be possible  similarly to why auroras can be different colors!

Below is a video showing this effect if you aren’t inclined to open band-aids simply for the fun of it: