Filling in again this week at Whom's request.

What have you been listening to this week? You don't need to do a 6000 word review if you don't want to, but please write something!

Feel free to give recs or discuss anything about each others' listening habits.

You can make a chart if you use last.fm:

http://www.tapmusic.net/lastfm/

Remember that linking directly to your image will update with your future listening, make sure to reupload to somewhere like imgur if you'd like it to remain what you have at the time of posting.

Probably in the majority of history people used to hunt, or kill farm animals for food without a second thought. But in the recent years it looks like the public opinion is shifting in a way when perception of eating meat is kinda like perception of homophobia or racism. Arguments against eating meat and for preserving farm animal lives are actively upvoted, and with this tendency being non vegetarian is already becoming "uncool" and eventually will be frowned upon, like littering.

Is that because hardcore vegetarians and animal rights activists got their voices spread in social media? Or it's mostly an environmental problem, particularly with large farm animals? Or humans are quickly becoming better, more civilized? If so, why meat eating is such a high priority issue to address when issues of people to people interactions are still far from being solved?

Intro

Hello everyone,

@wanda-seldon has been giving us an introduction to quantum physics. For now, she will be given a short break to prepare new stuff. In the meantime I will be covering some classical mechanics, more specifically thermodynamics. In part 1, we need to work our way through some of the more dry concepts, so we can understand and appreciate the horrifying implications of the fun parts. So I promise, this will be the most verbose one.

Some of you may have briefly seen a version of this posted, that was due to me misunderstanding the schedule with @wanda-seldon. If you saw that one, I will mention I rewrote nearly all of it to be more readable.

Now, on today's agenda: The basics of heat, work and energy and how it's all related.

Previous posts can be found here: https://tildes.net/~science/8al/meta_post_for_a_laypersons_introduction_to_series

Important note

If @wanda-seldon in her posts mention "energy", it's most likely in the context of energy operators, which is a concept in quantum physics. I'm not going to pretend I understand them, so I will not be explaining the difference. We will cover what energy is in classical mechanics. So keep that in mind if you read something from either of us.

Subject

Summarized

What is heat? Using a lot of fancy words we can describe it as follows. Heat is an energy that is transferred between systems by thermal interaction. And what is work? Work is an energy that is applied in a way that performs... work. The combined energy in a system is called internal energy. This type of energy can be transformed or applied to other systems.

These are a lot of new words, so lets break that down a bit.

Systems

A system is just a catch-all term for something that can be defined with a boundary of sorts. Be it mass, volume, shape, container, position, etc. A canister, your tea mug, the steam inside a boiler, your body, a cloud, a room, earth, etc. They are all systems because you can in some way define what is within the boundary, and what is beyond the boundary.

In theory, you could define every single nucleid in the universe as an unique system. But that would be counter-intuitive. In thermodynamics we tend to lump things into a system, and treat it as one thing. As opposed to Quantum stuff that looks at the smallest quantity. Calculating every single water molecule in my coffee would be pure insanity. So we just treat my mug as the boundary, and the tea inside the mug as the system. And just so it's mentioned, systems can contain systems, for instance a tea mug inside a room.

Energy

Energy is some quantifiable property that comes in either the form of heat, work. It can be transferred to other systems, or change between the different energy types. An example of transfer is my coffee cooling down because it's in a cold room. That means heat has been transferred from one system (my mug) to another system (the room). Alternatively you could say my hot coffee mug is warming up the room, or that the room is cooling down my coffee. Thermodynamics is a LOT about perspective. An example of transforming energy types is when we rub our hands together. That way we convert work (rubbing) into heat. It's really not more complicated than that. An interaction in this case is just a system having an effect on a different system. So a thermal interaction means it's an interaction due to heat (like in the mug example).

This brings us to an extremely important point. So important, it's considered "law". The first law of thermodynamics even. Energy cannot be destroyed, it can only change forms.

Your battery charge is never really lost. Neither is the heat of your mug of coffee. It just changed form or went somewhere else. The combined energy of all types that is residing inside a system is called internal energy.

Heat and work

Let's say we have a system, like a room. And all windows and doors are closed, so no energy can leave. In this system, you have a running table fan connected to a power line, getting energy from outside the system. The table fan is making you feel cool. Is the fan cooling down the room, heating up the room, or doing nothing? Think about it for a moment.

http://imgbox.com/CKtQLLOQ

The first thought of many would be to think that this fan would cool the room down, it sure makes you feel cooler! But it's actually heating up the room. As we remember, internal energy is the energy inside a system (room, in this case). The fan is getting energy from outside, and uses this energy to perform work. The fan accelerates the air inside the room, and this accelerated air will evaporate some of your sweat, so you feel cool. But as we remember, energy cannot be destroyed. So we are importing energy into the system, increasing the internal energy. Some of the work from the fan is also directly converted to heat, since the motor of the fan will get hot.

So if we are not getting rid of any of this excess energy, we are increasing the internal energy. And therefore actively increasing the temperature of the room.

http://imgbox.com/SAtqk7YG

To use a more tangible example: Simplified, this phenomena is why green house gases are bad. Lets define earth as a system. Earth gets a lot of energy from the sun. And a lot of this energy will be reflected and sent back to space. Green house gases will reflect back some of this energy trying to leave earth. So instead of having a roughly equal amount of energy enter the system (from the sun, from us doing stuff, etc) that leaves out in space, we have an increasing amount of energy on earth. This, as a consequence, increases temperature.

Implications

Now, what are the maybe not so obvious implications of this?

Waste heat, from supplied energy or inefficient work is a constant headache in engineering. If we cannot remove enough heat, we will actively heat up objects until they are destroyed. Thats why good cooling systems are important in cars, computers, etc.

Whats next?

Now this was not so bad. In the future we will cover phase changes, equilibriums, entropy, the heat death of the universe and briefly touch upon engines. So thats most likely two more parts after this. After that @wanda-seldon will take over again.

I plan on doing one main part per week, but if something is asked that warrants a small topic I might do smaller ones inbetween.

Feedback

Something unclear? Got questions? Got feedback? Or requests of topics to cover? Leave a comment.

What's this?

This post contains all entries of the "a layperson's introduction to" series. I will keep this thread up to date and sorted. This means this post is an excellent opportunity to try out the bookmarking feature!

Physics

Quantum Physics

Basics of quantum physics

Material Science

Classical physics

Thermodynamics

Computer Science

Artificial Intelligence

apathetic.
hardly wanna move, too
depressed to drink
pathetic.
see a demon's hand
on your closet door
forget it.
possession and a hell-
bound sentence better
than remembrance.
my uncle got so fucked
up that he passed, guess
it's genetic.

exhausted
tryna make depression
beautiful, poetic.
tired of this dance
between lethargic,
apoplectic.
brain on sober
tweakin every minute
schizophrenic. all
the thoughts i'm
barely eatin tryna live
up to aesthetics.

tired of my fucking
skin, a serpent's wish
to shed it.
i saw all the flags
drenched in red
how prophetic.
baphomet in
female form, they said
you'd be angelic.
my single dying wish
you'd be a little
sympathetic

-.

don't come
don't come
to my funeral.

don't cry
don't cry
at my funeral.

just know i
thought you
were beautiful.

even with your
knife at my throat
beautiful

.

where to go
no one's home,
honey can i call?

every day
feed the night
it's insatiable

i never thought
i'd come to say it
maybe its your fault.

i cant believe ive
come so low to say
that its your fault.

-.

i hope you kiss me,
hope you hold me,
when i see you in hell.
cuddle closely
and console me
when i see you in hell.
girl dont push me
will he? wont he?
boy how many pills?
all his poems,
magnum opus, testa-
ment and will.

if i cant know you
lay beside you
then somebody will.
dont wanna own you
or control you, you
do what you will.
i'll just sit here in
the cold, alone, and
write my will.
bottoms up a
litre wine a couple
hands of pills

What did you think of this week's episode of 'Doctor Who'?

Previous discussions:

• Doctor Who S11E04 'Arachnids in the UK'

• Doctor Who S11E01 'The Woman Who Fell To Earth'

• Doctor Who S11E02 'The Ghost Monument'

• Doctor Who S11E03 'Rosa'

I have a box of scrap parts of PLA left over from 3D printing and I'm wondering what to do with them. PLA can apparently biodegrade but only in really specific conditions I don't think I can achieve like keeping it at 60c. I know there is a device that can turn the scraps in to new filament but its way too expensive for me. What should with this stuff?

I'm not very familiar with how government works in the US, and I've always had this question.

Like, if states are reasonably independent, and it seems like there are some states who lean way more into the socially liberal side of the spectrum from providing universal healthcare (or at least some better healthcare policies) on their own?

okay

okay

what in the actual fuck

so i'm a southern boy myself. ever since i was a little kid my mom tried so hard to make me into a little cowboy. i was bought cowboy boots, cowboy hats, and boot-cut blue jeans. even at my young toddler age, i detested all of it lmao.

i was always a city boy.

i loved the idea of big cities like new york, los angeles, chicago, etc. hell, i even fantasized about spending my days in dallas of all places when i was in school daydreaming.

my music tastes trended as far alternative as my style in clothes and girls - in middle school i listened to everything from Shinedown to Disturbed to A Day to Remember to Dimmu Borgir (spooky!)

when i was in higschool - everything from showtunes (Phantom of the Opera) to Eminem to more metal (We Butter The Bread With Butter) to indie rock (Mumford and Sons)

but never in my life was country even a blip on my radar.

sure there were one or two songs you pick up that you get to know like

"Back When" x Tim McGraw

"Pretty Good at Drinking Beer" x Billy Currington

(my stepdad is a country musician. it's hard not to pick up something here and there.)

but

i just discovered a new genre of music (new to me).

i just discovered a new sound.

i just discovered my new favorite song.

and it's country.

Hank Williams III - "Ghost to a Ghost"

like oh my God

i just earlier this week discovered something called "Outlaw Country". i'd somehow managed to go my whole life without ever coming into contact with this.

will you listen to this fucking song??

it's the same classic country instruments that we've heard for decades.

paired with dark, angsty, grungy, emo lyrics.

with an incredibly metal breakdown serving as the chorus.

with a terrifically orchestral and bluesy viola/violin backing the entire song.

WHAT IN TARNATION!?

why did no one ever tell me there was an entire subgenre of emo cowboys running around talking about sleeping on the blacktop, relationship struggles, and popping hella pills

i now listen to country music and i'm never admitting it to my parents lmao.

if you didn't catch the link earlier, this song is a fucking work of art and literally brought me from awe to tears to fuck yeah! all in the span of six minutes in public in this cafe.

https://youtu.be/RoJwrSTIZM0

i think i've looped it back 7-8 times in a row now.

i'm floored.

what did you lot think?

do you listen to outlaw country?

please pass on any recommendations you have

C:

int main(void)
{
	puts("test");
	return 0;
}

Go:

package main

import "os"

func main() {
	_, err := os.Stdout.WriteString("test")
	if err != nil {
		_, _ = os.Stderr.WriteString("fail")
	}
}

Ruby:

10.times { |n| puts "test_#{ n }" }

XML:

<html>
  <body>
    <h1>test</h1>
  </body>
</html>

Saw a pic on Lil Peep's subreddit that listed out a song of his for every mood you could have.

I thought the list was a pretty good showcase of his work, and served as an awesome introduction to Peeper.

Copy my template or make your own and comment below with links of your favorite artist! Show off the range of their work and showcase some of your favorite tracks in the comments downstairs!

A Peep song for when:

(Don't wanna kill the whole list? * = must hear.)

you're overthinking - Overdose ft. Lil Tracy

you're heartbroken - nothing to u

you're really lonely - Praying To The Sky

*you feel hype as fuck - Witchblades

*you have a crush - Star Shopping

you miss your ex - Gym Class

*you're going through shit - Lil Jeep

you're in love - Worlds Away

you hate yourself - OMFG

you're high af - White Wine ft. Lil Tracy

*you're in a toxic relationship - (also leave pls) "Wake Me Up"

your ex moved on - Love Letter

you're gettin freaky - sex (last nite)

no one wants you - Not The One

you don't give a shit (in a good way) - Save That Shit

everything's falling apart - Nose Ring

you got hurt - driveway

they mean the world to you - High School

you're mad at the world - Life

you thought they loved you - Beat It

you want to scream and pull your hair out - Move On, Be Strong

*you're fresh out of a relationship - Awful Things

welcome to Peeper! what'd you think? what'd you love, what'd you hate? let me know!

#GothBoiClique

#WICCAPHASETASKFORCE