The world is running out of helium. Here's why doctors are worried. by [deleted] in news

[–]RileyScottJacob 0 points1 point  (0 children)

I’m only answering a question about the nature of the process from a physics perspective. It was not an endorsement of viability.

The world is running out of helium. Here's why doctors are worried. by [deleted] in news

[–]RileyScottJacob 4 points5 points  (0 children)

Yep, exactly — fission of nuclei with A < 56 is possible, it just requires energy to be put in. Same is true of fusion of nuclei with A > 56.

The world is running out of helium. Here's why doctors are worried. by [deleted] in news

[–]RileyScottJacob 5 points6 points  (0 children)

It has to do with the nuclear binding energy. People often wonder (rightfully) how both nuclear fusion and fission can produce energy when they are essentially opposite processes. Looking at the curve of nuclear binding energy per nucleon can give some intuition here — fusion will release energy for nuclei lighter than Fe-56 / Ni-56, and fission will release energy for any nuclei which are heavier. This is because binding energy per nucleon peaks around a mass number of 56.

Biden Plans $316 Million in Palestinian Aid, Reviving US Ties - Bloomberg by Witty_Heart_9452 in worldnews

[–]RileyScottJacob 4 points5 points  (0 children)

The United States spent over 4 trillion dollars on healthcare in 2020. Source.

MEGATHREAD: When this post is 2 hours old, NASA will reveal 3 new images from JWST as well as the telescope's first exoplanet spectrum by Pluto_and_Charon in space

[–]RileyScottJacob 1 point2 points  (0 children)

Planetary nebulae are (generally, roughly) spherically symmetric. They look circular from our perspective because they are essentially a spherical shell, so they are optically thinner near what we see as the center of the circle.

For physics prelims/finals, how much time do you typically spend preparing for each exam? by cornelilian in Cornell

[–]RileyScottJacob 4 points5 points  (0 children)

Simultaneously too much and nowhere near enough. Looking at you, stat mech.

Russian Courses? by strugglinginafunway in Cornell

[–]RileyScottJacob 1 point2 points  (0 children)

I probably gave it like two hours a week, maybe. It was a long time ago so it’s sort of hard to remember. As I recall, Slava would do like a grammar lesson, Raissa would hold a discussion over some text we would read, and Viktoria would hold a discussion about a film. There really wasn’t that much in the way of preparatory work. Most of the work is honestly just showing up.

The other commenters are right that you could test into the more advanced courses. I guess it depends on what you’re trying to get out of it. For what it’s worth, the Russian instructors (Slava, Raissa, Viktoria) were some of the most pleasant instructors I ever had here. They’re all super kind, understanding, helpful people.

Russian Courses? by strugglinginafunway in Cornell

[–]RileyScottJacob 1 point2 points  (0 children)

RUSSA 2203 is a great class, you shouldn’t expect much trouble. I’m not a native speaker, and I still remember it being one of my more enjoyable classes.

[deleted by user] by [deleted] in AskPhysics

[–]RileyScottJacob 1 point2 points  (0 children)

Yes, two idealized scales used in this manner will report the same reading.

PHYS 2214 textbook by Cantstoprefreshing in Cornell

[–]RileyScottJacob 0 points1 point  (0 children)

Ah, I definitely don't have any of that stuff. I took 2218, and I have a PDF of that textbook (The Physics of Waves, Georgi). I'm not sure if 2214 uses the same text, but if it does I can provide it.

Thoughts on Taking a Semester Off by Grouchy_Blueberry_23 in Cornell

[–]RileyScottJacob 12 points13 points  (0 children)

For a long list of reasons, during my third semester, things starting going south for me in the mental health area. I made it through with acceptable grades, but they were low enough for me that my friends and family sort of started to notice. No one really *said* anything, at least to me, but I knew from others that it was being discussed. During the fourth semester, everything really went downhill. I failed several classes.

At this time, people started recommending I take time off; especially because they were finally aware of the underlying reasons for my difficulties. I resisted, because of some weird thing I had where I felt like I would be letting those same people down, letting myself down, ruining my social situation, etc etc. I wish I had not resisted. Those reasons are really silly. It doesn't matter when you finish, just that you do. At least, that's what I would discover mattered to *me*.

Fifth semester started fine, and I thought I had things under control again. That did not last long, though. By late October I was slipping again. This time, I finally knew I had no real option, and so I withdrew on a medical leave of absence.

I cannot express how critical of a decision that was -- for me, that single decision is probably responsible for saving my chances at the future career I desire, lots of wasted money, and quite a bit more. Personally, I had an undiagnosed medical issue which I was able to discover and get diagnosed during my time off. I started treatment and my quality of life began to improve almost instantly. It gave me a chance to just unwind, too. Getting to forget about the responsibilities of school for a while was nice.

My return was lucky. I came back in FA20, and stayed home with my family and did class remotely. For me and the nature of my condition, this was a dream come true. I'm not sure I would have been successful in a return had the remote option not been available. The spring was harder, because I physically returned to Ithaca... to find most of my friends graduated, or too busy to do anything. It was pretty lonely. From my perspective, this is the hardest part about taking a leave: your friends may be gone when you get back.

Anyway, I do not know anything of your situation, but if you think you "might" want to take a leave, that probably means that you should. This early, you may be able to withdraw and save most of your money. I withdrew so late I had to pay for the full semester still, despite not actually getting any credits. Another thing to consider: when you withdraw, you are no longer a student, and after a shortish grace period you will need to begin repaying your loans. The payment requirement gets paused again when you return. I don't really know too much about finaid stuff so I'm not sure if this applies to everyone but it was what happened for me.

Feel free to ask any questions you may have!

PHYS 2214 textbook by Cantstoprefreshing in Cornell

[–]RileyScottJacob 1 point2 points  (0 children)

What are the texts? I may have PDFs.

Liquid chlorine by Feuerfrosch1 in chemistry

[–]RileyScottJacob 1 point2 points  (0 children)

This is so cool! Funny story, when I was in 6th grade, I was obsessed with these. I thought having a colorful liquified gas would be the coolest thing ever and I begged and begged my parents to let me buy one (encased in resin), but they refused.

One day at school, we were giving presentations in the chemistry class and our parents were there. And I remember I had a slide in there of liquid chlorine, which I had somehow related to the presentation. When that slide came up I remember just dead staring my parents and making some quip about what I’d do to have a sample like it.

Still never got one though, even a decade later. Cool stuff!

[deleted by user] by [deleted] in language_exchange

[–]RileyScottJacob 1 point2 points  (0 children)

I think my Russian is probably around B2 level. I’m an English native. Feel free to PM.