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hpr4019 :: Fairy lights and Powerful Pixies

Ken is visited by the ghost of procrastination, desperation and rambling

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Hosted by Ken Fallon on 2023-12-28 is flagged as Clean and is released under a CC-BY-SA license.
Volts, Amps, Ohms, Resistance, Current, Potential Energy, Ohms Law, AngryPixies. 2.

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Duration: 01:18:23


'Twas the night before Christmas, when all through the house Not a creature was stirring, not even a mouse;

OK wrong story.

In his lonely man cave, a HPR Janitor is visited by the ghost of procrastination. Two years later he is again visited, but this time by the ghost of desperation. And then finally by the ghost of rambling.

Today we learn about AC and DC voltage, about Ohms Law and how to wire up a LED to a USB connector.

A long rambling show which in the end came down to using ohms law to find the value of the resister.

Knowing any 2 of the 3 values in Ohms law will give us the resistor we need.

The current will be the same, so we can just measure, and it turns out to be 22 mA (milliamperes) or 0.022 amp. This is measured in Amps, and has the symbol I

The voltage we need to use up is 2 volts as we are going from 5 Volts USB AC Adapter to 3 Volts used by the two AA battery in series. Giving us 2 Volts with unit of V.

We can then find the Resistance measured in Ohms by dividing 2 Volts, by 0.022 Amps to give us 90 Ohms of Resistance.

The V is always on top of the triangle with I and R underneath.

So not having a 90 Ohm resistor a 100 Ohm would work just as well.


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Comment #1 posted on 2023-12-28 13:35:47 by Trey

Nicely done.

I love this "stream of consciousness" teaching approach for a podcast. I may need to try a similar method in the future, since I talk to myself all the time already while tinkering in my shop. The idea of angry pixies is a fun one, which works well enough to communicate the ideas. They may have been influenced a tiny bit by the mulled wine. :) Hmmmm... Maybe mulled wine would have helped me through my college electronics classes (Especially transform analysis!) Keep up the awesome work, and have a happy new year.
Comment #2 posted on 2023-12-29 11:12:23 by Reto

Audacity is overkill

Next time give it a try or better play with it NOW, because solocast combine (command) Run when all the segments are recorded - it does: Combine the segments Apply the noise reduction filter Truncate silence

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