It's interesting because it's very obvious, biologically, that the panda has a digestive system that has a carnivore past, and yet, the very plentiful biomass in bamboo forests just waiting to be eaten rewards the animals that can make use of it. So the giant panda may or may not be "optimized" for meat, but has generations that came out of the free food that is bamboo, so that their very survival depends on a herbivore diet.
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I remember reading that the common ancestors of all birds was carnivorous. Basically every herbivore bird descended from carnivores.
See also the giant panda and the red panda.
Actually I was off by a factor of 1000. That Camry needs to be raised to 7.3 km. Or you need 1000 of them. Or some combination of increased weight and height.
You're absolutely right.
I don't know why I thought to use grams instead of kilograms. I knew kg was the base unit for these conversions but just slipped for some reason.
Sorry whoops I was off by a factor of 1000 because I used grams instead of kilograms. The Camry needs to be raised 7.3 km. Or you need 1000 of them in one house.
is it really easier and cheaper to store the energy needed for a home in a chemical battery?
Yes. A 5kwh battery is about 50kg and smaller than a carry-on suitcase. String 6 of them together and you've got 30 kWh stored with no moving parts. Anker has that for about $15,000, maybe $30k installed.
How much does a 3-story elevator cost? What about one that can capture the stored potential energy on the way down, and not break down?
Potential energy (in joules) is mass (in g) times height (in meters) times 9.8 m/s^2 .
So in order to store the 30 kWh per day that the typical American house uses, you'd need to convert the 30 kWh into 108,000,000 joules, and divide by 9.8, to determine how you'd want to store that energy. You'd need the height times mass to be about 11 million.
So do you take a 1500 kg weight (about the weight of a Toyota Camry) and raise it about 7.3 meters (about 2 stories in a typical residential home)?(this is wrong, it's only 0.001 as much as the energy needed, see edit below)And if that's only one day's worth of energy, how would you store a month's worth? Or the 3800kwh (13.68 x 10^9 joules) discussed in the article?
At that point, we're talking about raising 10 Camrys 93 meters into the air, just for one household. Without accounting for the lost energy and inefficiencies in the charging/discharging cycle.
Chemical energy is way easier to store.
Edit: whoops I was off by using grams instead of kg. It actually needs to be 1000 times the weight or 1000 the height. The two story Camry is around a tablet battery's worth of storage, not very much at all.
Even if I didn't make that at my normal job, or it was non-business hours when I can't just go to work for money, I feel like $40 in 3 hours is pretty doable with just gig work (grocery/restaurant delivery, Uber).
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someone who knew the male in this meme
How can you tell that the Parapropalaehoplophorus septentrionalis is male?
I see a lot of objectionable behavior out in public. A lot of it is from children. But most of it is not. If I'm thinking through my 10 worst flight experiences, or subway experiences, or coffee shop experiences, none of them involve children. Children are mostly a mild annoyance (and I say this as someone who mostly doesn't like other people's kids), but mostly harmless.
So the reaction of singling out the children for immediate correction, through physical force and violence, seems to be selectively targeted, and makes me suspect it's just people who just don't like children. Unless these same people say that a person holding up the line, playing music too loud on the subway, getting too close in your personal space, throwing trash on the ground, catcalling women, using slurs in public, etc., all deserve to be beaten, too.
And for people in the thread who are saying stuff like "oh yeah you shouldn't beat your kids, but you should keep those children out of public places," it also calls to mind the way some people talk about the homeless or the disabled, like they're ruining your good time by simply existing within your vicinity.
We're all just trying to coexist. Being in public, in a place open and accessible to everyone else, is inherently going to involve compromise, where we're not able to exclude others (the deal that comes with them not being able to exclude you). You can't let other people aggravate you enough to, like, post a TikTok about it (which I also consider to be objectionable behavior).
Tiny Batman head shows up from time to time. Here's one from 2007.
I was popular within my niche, the nerds who were racking up all sorts of college credit and high standardized test scores while taking the most academically challenging classes offered by my school. Dated a bit, usually could get a group together in any given weekend night to hang out, could always find a group to watch rented movies or play pickup sports or play video games with (this was before home broadband so people had to lug their desktop computers to someone's house for a LAN party).
There was some exposure to the athletes (most of the athletes at my high school were pretty good students), the arts and theater types, goth types, etc., but I never felt that there was a true hierarchy in popularity of the different groups, just people sorting into what they preferred. I hung out with my friends, and I was one of more popular kids within my particular group. I had a blast.
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Like the Kumail Nanjiani joke about a new drug called "cheese," made by mixing Tylenol PM with heroin.
There is a need for more precise terminology. We should refer to "block" as stopping someone from interacting with you or your submissions/comments and "mute"/"ignore" as making it so that the person's own actions cannot be seen by you.
Just wait for that first time that you realize your doctor is younger than you.
The animation is actually slowed down. Kinesin can take something like 100 steps per second. Each step is about 8 nm, and they've been observed to move 600-1000 nm per second.
In reality it wiggles around in Brownian motion but the equilibrium of it "clicking" into place is so attractive that it keeps happening really fast.
Cable doesn't have rules, other than each corporate entity's own practices of what they're willing to publish/broadcast. Part of it is appeasing advertisers, and some of it is them wanting to gain market share, but it's all business reasons. And those same business reasons apply to websites and podcasts.
There's a book I read, Range by David Epstein, that really reinforces the idea that lots of experiences that don't cleanly fit into a CV are still very valuable. The core idea is that late specialization makes for better specialists, because very few fields stand alone. Having contextual background makes it so that you can better mix and match cross disciplinary skills, with your own experience and knowledge of yourself, to be better at whatever it is you're doing.
The examples used in the book are Roger Federer (played many sports and didn't specialize in tennis until much later than the typical pro), Django Reinhardt (never formally schooled in music but an amazing jazz guitarist even after he lost 3 fingers), Van Gogh (many failed careers before finding success as a painter), and a bunch of others.
But the core principle is the same: the real world is messy and doesn't boil down to simple factors, so having breadth is important when the system you come up in changes underneath your feet. The book also uses the counterexamples of Tiger Woods and the Polgar sisters who were dominant chess players, to describe how the fields of golf and chess give immediate, true, and objective feedback in a way that most of the world doesn't.
He was constructing his own languages and scripts in his teens, after having learned Anglo Saxon and Latin (and seeing how those fed into modern English), plus Esperanto.
He traveled all over Europe in the summers between university semesters, taking in the different landscapes, cultures, and languages.
He was a British Army Officer for World War I, leading units consisting of men from different backgrounds (class, education, trade) from his own. He devised a code system to bypass Army censors to keep his wife updated on his location and movements. And he experienced the horrors of being in the front lines of one of the most horrific wars in history.
Then after the war he became an accomplished academic, worked on the Oxford English Dictionary, specialized in Middle English and Old English translations, and translated several major works (including the definitive translation of Gawain and the Green Knight).
So by the time he started formally working on Lord of the Rings, he had built up such a rich set of experiences, skillsets, and knowledge that everything he knew was going into that world building.
No way a 25-year-old could have written Lord of the Rings. He needed 20+ years of adult experience to get to the point where he could write it.
Note that this statement also generally describes models for meteorology, medicine, aerodynamics, and cosmology. Lots and lots of science is done through statistical analysis and modeling.