I initially was going to cancel as well - I don't care that much about the fast shipping, and if you hit the minimum order, you get free shipping anyway. But, it means 3% back instead of 5% on the Amazon visa, so if you spend more than 150/12*50=625/month, prime is negative cost. Especially using it for many groceries, I usually hit that.
If you rapidly cool the drink, you're definitely right - energy would flow PCM -> drink. Otherwise, it's semantic if GP is correct. There would be dynamic equilibrium, i.e. flow of thermal energy in both directions, but no true flow from PCM->drink.
3a) drink cools to 140-epsilon before PCM liquifies fully
4a) PCM gives energy to drink in dynamic equilibrium, while also losing energy to environment, solidifying
5a) PCM is entirely solid at 140
6a) PCM drops below 140. drink gives energy to PCM and PCM to environment. drink -> PCM thermal conductivity is presumably much higher than PCM -> env, so drink and PCM remain at same temp
OR
3b) PCM liquifies fully before drink hits 140-epsilon
4b) drink and PCM stay at thermal equilibrium (see 6a) while cooling toward 140. energy flows drink -> PCM and PCM -> environment. The former is faster, so the PCM continues liquifying
5b) PCM is entirely liquid at 140. Due to thermal equilibrium, drink is also at 140.
In addition to the normal vaccuum insulation layer, it has a layer that does a (constant-temperature) phase change at ~140F. If your drink is hotter than this, energy flows out of the drink, cooling it and liquifying the layer. If you drink is cooler, energy flows into the drink, solidifying the layer.
> The formula looks at the variables below, and then spits out a "number" for every Googler. Each PA VP gets a % to cut, and as such there is a threshold. Anyone below that threshold gets RIF'd.
Variables are:
1) Location of labor. US Premium Plus was largely impacted versus cheaper areas.
2) Tenure and performance in level.
3) "Runway" of comp. (e.g. base salary vs MRP. eg. .8 of MRP Googlers have a long runway, vs 1.x of MRP Googlers are basically top of band, and 'tenured' with no runway except promo
4) Promo velocity
How are you not informed in advance? Every job I've had, there's a contract I sign in advance with all terms, and no addendum on day one. I'd think you could refuse to sign an addendum, and even sue for promissory estoppel if they fire you for not signing.
I honestly forget. I don't think they were ever on probation per se, but it's not like SH was blindsided. There was plenty of awareness that admin was increasingly unhappy. What I won't claim to understand is what pushed them over the line to actually doing it. I think it was more slow, evolutionary decreasing of tolerance for everything than any particular incident.
I'm bitter about the whole thing, and also the upcoming [renovation of EC](https://www.reddit.com/r/mit/comments/nfpumq/east_campus_is_...) (the next dorm over, physically and culturally). The building is realistically past due for some TLC, but it's hard not to feel like it's motivated from more than that.
Admin just doesn't care that much which speakers are allowed on campus. Like many progressive things students loudly champion, it's pretty immaterial and easy to just give in. It's not like it affects MIT's status or funding as a world-leading research institute.
By contrast, Senior House was a significant legal liability due to large, public parties with a habit of sending people to the hospital for more interesting reasons than booze. That, the institute has financial, practical, concrete reasons to care about.
It's unclear to me that SH created more liability than frats and alcohol, but maybe, and it was certainly the perception.
What advantages do hydrogen cars have over ICE or electric? I know very little about them. Electric, optimistically, is cost effective (especially if you have solar panels) and convenient. ICE at least has industry momentum going for it. But Hydrogen? Unsarcastically, why?
For the kind of problems in physics 101, the Lagrangian is just kinetic energy minus potential energy: L = T - U. This is definitionally true; there's no "why" to that. Think of L as the formal specification of a system. There's no point in asking "why does this mass on a spring have L = 1/2mv^2 - 1/2kx^2": that equation specifies the problem.
In higher level physics, e.g. QFT, there are often identifiably kinetic and potential terms as well. However, there are also often other terms. At that level, you generally write L = sum of the most general possible terms that don't violate symmetries you want the system to have. This ability to work backwards from symmetries to L is to me the more useful perspective on Noether's theorem than going from knowing L to the symmetries.
> Do I define q(s) any way I want, or do I solve q(s) given the constraints of the system?
q(s) is the function which minimizes the time integral of L, and is solved for via the [principle of least action](https://en.wikipedia.org/wiki/Stationary-action_principle), which requires functional derivatives to understand. Most physicists, myself included, only marginally understand the math here and do a bit of hand waving. "d" "del" "delta" potato potahto.
The principle of least action also generates "equations of motion" from L. These are the differential equations that can be solved for x(t).
So, in short: a system is formally specified by its L, which has measurable meaning only because of the principle of least action.
If you didn't specify the principle of least action, or something else, it would be nearly meaningless to give an expression for L. You might as well say: "the mass on a spring has a potato of 1/3kx^97 - 1/2m^8*v^3 + 3". "Nearly" in that at least that would tell me that two systems with unequal potato are different systems.
Sympy live shell is decent, and the latex rendering is pretty sweet. But, it's on ancient versions of everything, runs slowly, and has a C- UI.
Instead, I use Colab with Sympy + latex output and matplotlib (and most other things you could want to import, pre-installed). It's running new versions of things, and backed by more power, with an option to pay for even more. The latex rendering took a bit of poking around stackoverflow, but works just fine.