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  1. anorlunda

    Shock wave through a liquid metal filled steel tube

    How about something like water hammer?
  2. anorlunda

    I am Muze

    Welcome to PF. Real persons are welcome.
  3. anorlunda

    Ethical Discussion -- Engineering used to create innovation versus destruction

    It is worth mentioning humility. In my case as a power engineer, I know that making power creates pollution, and that it brings many benefits to the public. There is a trade-off. Is it up to me as an engineer, or to the public to decide if the trade-off is worth it? It would strike me a...
  4. anorlunda

    Ethical Discussion -- Engineering used to create innovation versus destruction

    Excellent question. Certainly the IEEE doesn't enforce it, that I heard of. It may result in loss of business if customers object. It may result in loos of employment if employers object. For those requiring a license, breach of ethics can result in loss of license. Disbarment of an...
  5. anorlunda

    Ethical Discussion -- Engineering used to create innovation versus destruction

    I think this thread is OK under engineering rather than general discussion. Engineers do think about ethics. We do have codes of ethics that we follow. Ethical considerations are sometimes slightly different for engineers, scientists and other professions. My field has been electric...
  6. anorlunda

    New Member Introduction

    We are very glad to have you. Welcome to PF. I like the DrEntropy name.
  7. anorlunda

    Python Finding the day from a given date

    Others have mentioned the 100 year and 400 year corrections. If you go longer, there are more corrections. Because there are 365.2425 days in one year (rounded to the nearest 0.0001). The real purpose of the question is to see whether your plan to handle invalid inputs. How about a...
  8. anorlunda

    I Running a microwave oven empty

    :welcome: I don't know if this applies to today's microwaves, but:
  9. anorlunda

    Python Finding the day from a given date

    No matter how elaborate you make the formulas, leap years, 400 year leap, ... it will have a finite upper bound of validity. I would write one complex enough to satisfy me, and then add a range check on the input date, and output an error if it is out of range.
  10. anorlunda

    1.5 in-line/pigtail day/night sensor?

    Welcome to PF. Sorry, I did a search on that and didn't find anything.
  11. anorlunda

    Chemical/Paint DIY Sabatier Reactor

    Let's start with the basics. How many pounds of carbon per year do you need to capture to declare it a success?
  12. anorlunda

    A Time derivative jump of the electric/magnetic field

    What about a radio wave encountering a wall?
  13. anorlunda

    Random Rounding in Google Sheets

    An additional speculation is that the program a certain number of cells are created and populated with default empty cell values on startup. Later, more rows and columns can be added, and populated with empty cell default values. It would be a bug if those two cases of default values were not...
  14. anorlunda

    Why the fascination with intermittent renewable energy sources?

    [Edit, missing quote added.] If you look at PF archives about home solar/wind projects, they almost always begin with the requirement of producing at least as much energy and power as they already consume. Very few begin by reducing their own demand. In fact, continuing to advance...
  15. anorlunda

    Electrical engineer student

    Welcome to PF. We are glad to have you. We even have homework forums for help with your problems. Guidelines for students and helpers | Physics Forums
  16. anorlunda

    Heat Transfer Through SS Corrugated Tubing

    I don't know how accurate you need to be. As a first guess, I would say that surface area is the dominant property. Therefore, if one meter of corrugated tubing has twice the surface area as one meter of smooth tubing, I would say that it is equivalent to two meters of smooth tubing for...
  17. anorlunda

    Thermocouple Accuracy and Noise?

    This article has a small discussion on each type. I would ignore the ADC, it should be adequate for any of the types, and thus not the limiting factor in their quality or performance.
  18. anorlunda

    Hello everybody!

    Welcome to PF. We're glad to have you as an active member rather than a lurker. It is somewhat mysterious for us wondering how many long-term lurkers we have.
  19. anorlunda

    I Simple problem for experts... (work done lifting weights at the Gym)

    That is a much more useful way to define workout energy/power. You can increase your heart rate by just sitting to watch certain videos (or by reading certain threads on PF :-). Even that burns nonzero quantity of calories.
  20. anorlunda

    Why the fascination with intermittent renewable energy sources?

    I agree. In fact, the first step in every renewable energy product should be to reduce demand. Alas, it sometimes seems that many people are eager to be green if it means writing a (reasonably small) check. But don't ask them to change their lifestyle or standard of living. An exception to...
  21. anorlunda

    How to detect an inductor's back EMF?

    Have you studied basic electricity? Ohm's Law. Kirchoff's voltage and current laws?
  22. anorlunda

    How to detect an inductor's back EMF?

    Yes, as in any circuit. However, the answer is not a single value, it is a function of V versus time. If you plotted the curve, it would look something like that in #10. You could spot the peak voltage from that. The simple circuit applies until the moment a spark is ignited (if ever)...
  23. anorlunda

    Hi guys

    Welcome to PF. We have several forums that can be relevant to your interests, especially in engineering. Be aware that our rules do not allow solicitation of personal contacts, nor advertising. We are not like Linkedin. It may be worthwhile to have a look at those rules. Physics Forums...
  24. anorlunda

    Random Rounding in Google Sheets

    This is just a guess. The number may be fine, but the default formatting of that cell may be different. You can test that by changing the number format of the offending cell. Increase the number of decimal digits displayed. Why the default may be different for different cells, I have no idea.
  25. anorlunda

    Chemical/Paint DIY Sabatier Reactor

    If you want to capture carbon and have something to sell to build things, plant a tree. Almost all the weight of a dried tree is captured carbon.
  26. anorlunda

    Did the Germans have a chance to win World War II?

    Then why ask the question? That is a poor way to start learning about WW2. You would have to learn before understanding answers to the question. Is this a school assignment?
  27. anorlunda

    Security Versus Programming Language

    I think we are in agreement, that we can't blame insecurity on the choice of programming language. The comment referenced in the OP implies that insecurity is the fault of the C language. Performance is a different subject. The desire for performance is hardly unique to the OS. Also, no...
  28. anorlunda

    B Is Radioactive Decay Uncaused/Causeless?

    I think "cause" is not the best word for your question. If we have N nuclei, all identical. In a period of time, some may decay, other's don't. That is a "random" process. The physics phrase that better fits your question is "hidden variables". Is there some variable or property of the...
  29. anorlunda

    Extinction 65 millions years ago

    Welcome to PF. Dinosaurs are extinct, but PF lives on. 😉 We have a special sub-forum for SF writers that may interest you.
  30. anorlunda

    Security Versus Programming Language

    It might be nitpicking, but I could write a secure function SECURE_TEXT_FIELD to eliminate the injection problem. But then I depend on the programmer to use the function everywhere, and third parties will be forever suspicious that he did not. A language feature does not depend on the...