Recent content by 1940LaSalle

Thanks

We all know from Euler's identity that exp(iπ)=-1. And from the laws of exponents, exp(2iπ)=(exp(iπ))²=1. Further, for any real number a≠0, a⁰=1. Then, since two things equal to the same third thing are necessarily equal, exp(2iπ)=(exp(iπ))²=a⁰=1. Here's where I'm wondering if I've stripped...

The word "day" has at least two if not more common connotations: 1. The interval required for earth to make one rotation about its axis; i.e., ~24 hours. 2. The variable interval between sunrise and sunset. I'm looking for unambiguous terms to differentiate the two such that one could say, "On...

Largely what the title says. I'm a retired chemical engineer, but for my own re-education, I'd like to review my college physics courses. Those were more than 50 years ago, and a portion has slipped away from lack of need/use. So...how about recommendations for general (say, 200 or 300 level)...

I want to lay out an analemmatic sundial, with a true figure 8 analemma for the gnomon position instead of the more common date marks. Everything I read shows that the ordinates of the points on the curve are a function of the sun's declination on a given date. Further, I'm also given to...

Apologies. Didn't see this thread until today and didn't see the date, either. Anyhow: I know of two articles published about 9 years ago that address these topics pretty well. Send me a PM with your e-mail and I can provide PDFs of these articles if you're interested.

Assuming you're after fairly rough-and-ready engineering values, I'll try offering some comments: 1. The enthalpy of fusion is a rather weak function of temperature. For most engineering purposes, assuming it's temperature independent is not a bad approximation. For the rest of the...