Lesson #359: 1 Planck

Today, I learned that the smallest unit of measure is a Planck.

A Planck measures 1.616199(97)×10−35m, which is really, really, really effing small.

So this is kind of a cheat because I don’t actually quite understand the use of the Planck length. I know it’s a constant in quantum physics and is directly related to Planck’s constant (h-bar*, which I know a little more about because I happen to know that ΔE x Δt  ħ/2, which is Heisenberg’s Uncertainty Principle), and I know that it is the outcome of taking Għ/c3 (the square root of the gravitational constant times Plank’s constant divided by the speed of light cubed), but outside of that, my grasp of quantum physics is so limited that the entire concept is hard for me to wrap my head around. Especially now that I’m not living with physicists who were able to dumb everything down for me.

Still though, it’s a good thing to know for Jeopardy! or at a random party.

*My physicist friends used to joke that someday they were going to open up a bar and call it H-bar, but it would be written like so: Ħ. I fully support that idea! 

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Lesson #319: How X Became the Unknown

Long story short, X is the unknown because there’s no “sh” in Spanish.*

This is honestly one of the most interesting things I’ve ever learned. It’s so concise and well explained, so I’ll just let Terry Moore take it away.

*Here’s the etymological breakdown for the word algebra in case you were unconvinced of Moore’s authority.

Lesson #255: How Far You Can See

I’m visiting my grandmother on the way down to the Mid-Atlantic city I’m moving to and the discussion of how far one can see standing on flat land came up. The average answer is around 3 miles and it’s figured out with this equation:

(r+h)squared = r squared + d squared

Solving for me at 5’7″, that’s…

(3961.301)2 = (3961.3)2 +d2

15691905.612601 = 15691897.69 +d2

7.922601= d2

d = 2.81471

So standing on flat ground at no elevation, I can see about 2.8 miles.