Activity for dmckee
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Comment | Post #283511 |
You have two distinct questions here. I've followed @Olin's lead in answering the electron-proton question, and suggest that the question text be edited to focus on that case alone. (more) |
— | over 2 years ago |
| Comment | Post #283293 |
@Istiak There is no need or expectation that you are in school to read a text, but publishing industry pressures drive most texts into those rough categories. The only exceptions that spring to mind are self published online (and so immune to industry pressures). But in order to recommend books to ma... (more) |
— | over 2 years ago |
| Comment | Post #283293 |
That said, authors don't write down every detail of every development: they expect readers to see some steps. How much they expect depends on the level of the text, the specified mathematical prerequisites, and the author's personality. Some texts are terse and expect a lot of the reader, others are ... (more) |
— | over 2 years ago |
| Comment | Post #283293 |
What level are you interested in. In the US (at least) it is typical to talk about "introductory", "upper-division", and "graduate" level texts. Introductory texts represent the first year of college instruction in physics and survey mechanics, thermal physics, and E&M in brief (the mechanics section... (more) |
— | over 2 years ago |
| Comment | Post #283046 |
While one can find an historical origin for the units in modern system they won’t be the original origin. Organized systems of units go back a long time. I’d guess they date back to roughly the origin of writing (because both relate to trade) with refinements piled on as necessary. We know a lot, for... (more) |
— | over 2 years ago |
| Comment | Post #280916 |
It’s worth noting that there is no direct relationship between indexes of refraction (at the top of the post) and corrective diopters (at the end). The closest you come is the lens-makers formula which tells you how to take those two numbers and build a suitable lens. (more) |
— | about 3 years ago |
| Comment | Post #280385 |
@celtschk "Natural units" is a broader term—it can refers to any scheme where you drop constants—and I was educated before "Planck units" had become popular. For instance I took general relativity from James Hartle (while he was developing his textbook on the subject) and he described the units he us... (more) |
— | over 3 years ago |