this post was submitted on 15 Feb 2024
457 points (95.4% liked)

NonCredibleDefense

6763 readers
987 users here now

A community for your defence shitposting needs

Rules

1. Be niceDo not make personal attacks against each other, call for violence against anyone, or intentionally antagonize people in the comment sections.

2. Explain incorrect defense articles and takes

If you want to post a non-credible take, it must be from a "credible" source (news article, politician, or military leader) and must have a comment laying out exactly why it's non-credible. Low-hanging fruit such as random Twitter and YouTube comments belong in the Matrix chat.

3. Content must be relevant

Posts must be about military hardware or international security/defense. This is not the page to fawn over Youtube personalities, simp over political leaders, or discuss other areas of international policy.

4. No racism / hatespeech

No slurs. No advocating for the killing of people or insulting them based on physical, religious, or ideological traits.

5. No politics

We don't care if you're Republican, Democrat, Socialist, Stalinist, Baathist, or some other hot mess. Leave it at the door. This applies to comments as well.

6. No seriousposting

We don't want your uncut war footage, fundraisers, credible news articles, or other such things. The world is already serious enough as it is.

7. No classified material

Classified ‘western’ information is off limits regardless of how "open source" and "easy to find" it is.

8. Source artwork

If you use somebody's art in your post or as your post, the OP must provide a direct link to the art's source in the comment section, or a good reason why this was not possible (such as the artist deleting their account). The source should be a place that the artist themselves uploaded the art. A booru is not a source. A watermark is not a source.

9. No low-effort posts

No egregiously low effort posts. E.g. screenshots, recent reposts, simple reaction & template memes, and images with the punchline in the title. Put these in weekly Matrix chat instead.

10. Don't get us banned

No brigading or harassing other communities. Do not post memes with a "haha people that I hate died… haha" punchline or violating the sh.itjust.works rules (below). This includes content illegal in Canada.

11. No misinformation

NCD exists to make fun of misinformation, not to spread it. Make outlandish claims, but if your take doesn’t show signs of satire or exaggeration it will be removed. Misleading content may result in a ban. Regardless of source, don’t post obvious propaganda or fake news. Double-check facts and don't be an idiot.


Join our Matrix chatroom


Other communities you may be interested in


Banner made by u/Fertility18

founded 2 years ago
MODERATORS
 
you are viewing a single comment's thread
view the rest of the comments
[–] Redjard@lemmy.dbzer0.com 8 points 10 months ago (1 children)

There is a cool easy-to-show fact that you can never make something hotter than the light source my focusing its light.
Since otherwise you could take heat and divide it into a hotter and colder region, decreasing entropy without using energy.

[–] nicoweio@lemmy.world 3 points 10 months ago (1 children)

I'm not sure about the easy-to-show part, but take a look at the Brightness Theorem / Conservation of https://en.wikipedia.org/wiki/Etendue if you want to learn more.

[–] Redjard@lemmy.dbzer0.com 3 points 10 months ago (1 children)

The easy to show part was the second sentence of my comment.

This is really useful physics trivia, because the basic truth is easy to show from a simple law, but the detailed explanations go quite in-depth.

With lenses, you trade bewteen angular accuracy and light density.

For a challenge, try it with LEDs. Where do you find the source "temperature", you can get from focusing an LEDs light?

[–] nicoweio@lemmy.world 2 points 10 months ago (1 children)

That's an intriguing question. My first guess would be it corresponds to the diode's band gap?

[–] Redjard@lemmy.dbzer0.com 1 points 10 months ago

Thats definitely hugely relevant, yes.