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It’s already Back To School season.
Then as soon as school starts comes Halloween Season.
Then after Halloween comes Thanksgiving.
And that’s just Christmas which brings us straight through into next year.
The year is over, basically.
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These are my best-of for randomized Garfield strips.
Tonight I bought some grilling supplies and I had to convince my dad to let me leave some recently purchased lighter fluid in our garage rather than outside (turned-off electronic lights may be considered a “heat source”), and then I went back into my bedroom where he had left the 7-lb paper bag of instant-lighting charcoal, in front of a pile of books and a cardboard box by my bedside.
I noticed a phenomenon with the dandelions today. On some hills, an entire side would have mostly living (blooming) flowers, and the opposite side would have mostly dead (seeding) flowers. This was the north side, and I suspect it’s where they get the most sun. You can see it here (except for that errant patch at the bottom).
And a bit more dramatically here.
And here is a patch of dead flowers in a crevasse, surrounded by living flowers on higher ground.
No matter how long the slinky is, the bottom of the slinky will stay still (hover) until the top reaches it. Even if the slinky is over 1000 feet long.
No. No. No. Don’t just say “Physics!” and leave it at that. That’s not physics. That’s almost superstition.
What do you think is going on here? Let’s look the situation over.
The slinky has a spring force that pulls both ends together in some fashion. We could simplify this idea to one weight at the top and one at the bottom, though we know the mass is spread throughout. At the top you have the weight of the entire spring at equilibrium with tension from the hand pulling/holding it up. At the bottom you have weight of the bottom at equilibrium with tension from the spring (F=kX, physics!).
Now you release. The top has zero tension but gravity and spring force to pull it down. The bottom has gravity for the moment still at equilibrium with the spring force. We see above that not only the bottom but each point in the slinky continues to “hover” until the top rolls down to it. But in our simplified version, shouldn’t the bottom pull down, albeit at a slower speed than the top, as the distance between top and bottom (and therefore spring force) decreases?
Here is the video this gif came from. The answer they give is that information about the change in tension takes time to travel, which it does in the form of a compression wave (how we see it bunching up). So think about this now as each little point of the spring having its own set of forces (feeling gravity on its own mass, but mostly tension both downward and upward due to the points above and below pulling on it). A point halfway down pulls in both directions and continues to do so to the same degree (experiencing only the points right below and right above it) until the point above it comes in closer and pulls on it less, and that point won’t change until the point above it pulls less, and so on. So at every point, both distance and tension to other points stays the same until this cascade of changes, as a compression wave catches up.
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I’ve been playing some Minecraft:FTB and I came across the new research system in Thaumcraft 4. I was trying to strike a balance between the tedium of writing out diagrams and the boredom of using the research helper when I came across GraphViz.
So here’s a network diagram of all the current aspects. The arrows point from a compound aspect to those used to create it. For researching notes, however, the direction of the arrow doesn’t matter. You can hop from point to point and see how many steps that path takes. Generally the farther right the aspect is, the more costly it is to make from the primal aspects.
Pluto’s moon Charon is nearly half the size of the planet itself. It doesn’t rotate, which means the same side of pluto always sees the same side of Charon.
It’s so amazing to think that the best images we have of Pluto and Charon are just a handful of pixels wide, and yet we know its size, composition, movement, and other things.
To clarify one thing, Charon does rotate, it’s just synchronous (or tidally locked) with Pluto, like our moon with Earth. It makes me wonder (as someone without much background in this) if certain distances and rotation speeds are sought out by moons in a “path of least resistance” way.
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Where I work there’s a customer satisfaction survey that asks our shoppers to rate us in a number of factors by a 5-point scale: highly dissatisfied, dissatisfied, neither satisfied nor dissatisfied, satisfied, highly satisfied.
An average of 75% — this comes out to 1:1 between “satisfied” and “highly satisfied” if no lower choices are given — is considered really bad. What’s passable is about a 7:3 ratio.
A person would think that being judicious about the survey, telling us which aspects are better than others, and saying “satisfied” most of the time would be considered good. To a rational system, it would. Not ours, and I bet not most stores and other places you might find these surveys.
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