# anorlunda's Recent Activity

1. ### anorlunda replied to the thread Limiting output voltage of an electric fence energiser.

Google 10 KV surge arrester. I found several starting at \$13.

Sep 17, 2017 at 6:29 PM
2. ### anorlunda replied to the thread High Current low Voltage.

Whoa! That is a huge current. In power plants, we use isolated phase bus ducts for half that much current. Interrupting such...

Sep 17, 2017 at 11:02 AM
3. ### anorlunda attached a file to the thread Why do we need a switch before a relay?.

The answer is (a), except that most damage occurs when you try to open the switch and stop the current. The picture below shows the...

Sep 17, 2017 at 7:13 AM
4. ### anorlunda replied to the thread Studying Is it possible to understand quantum mechanics in student life?.

Let me suggest that you search "susskind quantum" on YouTube. His 10 lecture course uses only moderate math, but he does it right, no...

Sep 16, 2017 at 12:03 PM
5. ### anorlunda replied to the thread Piezoelectric transducer current.

You can use an amplifier plus external power to amplify a signal. But if your goal is to generate power, add more transducers in...

Sep 16, 2017 at 8:00 AM
6. ### anorlunda replied to the thread B Is Newton's 3rd law sufficient to explain buoyancy force?.

Sep 15, 2017 at 2:22 PM
7. ### anorlunda replied to the thread B Is Newton's 3rd law sufficient to explain buoyancy force?.

:welcome: Wikipedia has a good article on buoyancy forces. https://en.wikipedia.org/wiki/Buoyancy Read that first and then if you...

Sep 15, 2017 at 12:56 PM
8. ### anorlunda replied to the thread I What Materials Absorb IR The Best?.

That's better focus on better insulation, not something that seems better but isn't.

Sep 15, 2017 at 9:38 AM
9. ### anorlunda replied to the thread I What Materials Absorb IR The Best?.

You are asking for help on cheating. Shame on you. Leave the lens cap on the IR camera. That will absorb the IR.

Sep 15, 2017 at 9:32 AM
10. ### anorlunda replied to the thread B Change in direction of velocity.

Not true. Speed has no sign, but velocity does. If the initial velocity is +1 in some direction, then the same velocity in the other...

Sep 14, 2017 at 7:22 PM
11. ### anorlunda replied to the thread B Change in direction of velocity.

Acceleration is change in velocity divided by elapsed time. How much elapsed time?

Sep 14, 2017 at 7:15 PM
12. ### anorlunda replied to the thread Affordable hurricane-resistant housing, can we do it?.

That's easier said than done. Hurricanes, tornadoes, floods, fires, earthquakes, volcanic activities, blizzards, ice storms, sea level...

Sep 14, 2017 at 6:40 PM
13. ### anorlunda replied to the thread I Homebrewing a spectrometer.

Paint stores in the USA now have machines that very accurately measure color. i don't think they are very sophisticated. Perhaps the...

Sep 14, 2017 at 8:01 AM
14. ### anorlunda replied to the thread How are/were computers used in jet engine design?.

As a writer, for which writing tasks do you use words? That illustrates how your questions sound to me. The flippant answer is all...

Sep 13, 2017 at 4:52 PM
15. ### anorlunda replied to the thread How are/were computers used in jet engine design?.

You ask an engineer what tasks need equations, WTF. I'm afraid you don't have the perspective to write this article. You need to...

Sep 13, 2017 at 4:32 PM