Surprising History & Physics of the AC Transformer

History of electric transformers from Faraday through Lenz, Sturgeon, Callan, Ruhmkorff, Gaulard, Westinghouse and more (+ what Tesla did and didn’t do in the evolution of electricity).

Link to script:

Links:
0:45 "Fasten your seatbelt" is from the amazing must-see movie "All about Eve"

2:19 Movie of Faraday discovering electro-magnetic induction is from the fantastic video

11:08 Ruhmkorff coil demonstrations (beautiful)

20:27 "The Simpson's" (We obey the laws of thermodynamics..."

0:00 Intro
1:05 DC Transformers
13:30 AC Transformers
27:36 Transformers & War of Currents
34:21Tesla's Influence
49:18 Conclusion

[Kathy_Loves_Physics]

I thought this pinned comment could be a good place for people to add (respectfully) things in history and physics that you think I made mistakes on. Please nothing about sound quality or other superficials in this thread. Let me start:

1) 4:40 I said that Lenz didn't use shock because it wasn't mathematical, but (after thinking about it) it was probably because the magnets at the time were not strong enough to cause a discernable shock.
2) 28:40 I said that Westinghouse started his company in January 1886 without a working AC system, but he had told Stanley to work on AC as soon as he heard about Gaulard in the summer of 1885, so he probably had a working AC system by then, just one without working transformers.
3) 31:10 I cut out that Stanley not only claimed to be the inventor of the industrial AC transformer, he also claimed to be the person who convinced a reluctant Westinghouse to take a risk on the project. Stanley was a real piece of work in my opinion.

[andyfeimsternfei]

Thank you, Kathy! I have spent the last 43 years working on electrical equipment dating from the early 1890s, and it is a joy to see someone doing such detailed research on topics so misrepresented throughout history. You're a treasure!

[archstanton_live]

In these days when "I researched it." translates to: "I read a Wiki and watched some YouTubes", it is most refreshing to see someone that has taken the research to the primary source level of "comments from contemporaries."

[bobpotter]

I have worked in electrical engineering for 54 years. I like millions of others have accepted and used the formula and theories of these people of the past without much question. You bring the history of electricity to light in a wonderful and entertaining way. Thank you.

[malatestov]

Hi Kathy! I am an electric engineer from Spain, and I can't thank you enough for your amazing work. Going through the history of electricity with you is a joy. I will share your videos with my colleagues and other Spanish science communicators. This stories have to be known!

[sirwinston]

10/13/23 - OK, BSChE here practicing as a mechanical engineer for more than 30 years. I took two EE courses in college. Was never a fan of electromagnetism. Fast forward 30+ years and I am making up for lost time. I recently took an undergrad class in Electrodynamics (Griffiths, 4th ed.). Studying QM and DiffEq in my spare time and watching all the "Kathy" videos. They are amazing. Thank you Kathy. sw

[miken]

I think the guy who invented coated copper wire should deserve all the credit, everything was built off his invention.

[MrHichammohsen]

I am not sure if we, the subscribers and watchers, really appreciate the research you do for us Kathy!
You are the hero we need, but definitely not the one we deserve.
This is not just teaching the history of electricity, but also a lesson on how to do research abjectively

[pjmoran]

As an engineer, is pretty cool to hear all the backstory. We shyed away from history and did the equations. Keep up the great work!

[garyradtke]

Thanks for the real history. I have learned over the years that most inventions aren't developed by one person but the conglomeration of ideas and experiments. The one that gets the credit is the one that combines all of the correct ideas and creates the success. I would bet the Write brothers used others failures and discoveries in flight to make decisions about their theories.

[donberg]

As a field engineer and inspector, your work is BRILLIANT! Most electricians, electronic technicians engineers don't know the historical facts as you present them & your book is facinating!

[tonyc]

Somebody give this fantastic woman an award.

[TexRenner]

While my computer was broken you have become very professional! I'm so glad to see that you're as filled with joy for your work as you ever were, and the spirit of wonderment that has made Kathy so compelling is alive.

[willisfouts]

Young Miss Kathy, I must give credit where it’s due.
As I’ve zipped through your channel, watching all and some over and again, I do believe I’m starting to piece this whole crazy story together. No, in fact I am -starting- to grasp these ideas and arguments and experiments and papers you’ve shared here, well enough to begin asking pertinent query, to myself, in my head of course!
And you’re ability to share this knowledge, in your manner, cadence and diction … the exuberance on your face while you’re speaking about what you know. You enjoy.
You, as a teacher must have many successes with students pursuing what you taught them.
That’s a rare gift, dear friend. And you share it humbly, with zeal. Another wonderful attribute.

Sorry for running on like that, but I couldn’t describe it with fewer words. 😂 Thank you. Another great video!! Can’t wait for the next one!

[rameshkp]

Super. Thank you so much. Excellent history of electricity.

[ramoncf]

AC was a combined effort from brilliant minds, many times with people working in the same ideas simultaneously, just as it happened with many other inventions like the radio, plane, etc. Only in the movies they portray this geniuses which create in their lab everything from scratch.

Thank you Kathy, as an electrical engineer these videos are invaluable.

[jomarescobido]

You just made another Faraday's fan! Thank you so much Ma'am Kathy!

[cowboybob]

The content on this channel is so compact and accurate. It's also mostly new to me, the answers that is, not the questions. Because of that it feels almost disrespectful to not study each post and take notes.

[ralphomholt]

I've spent a lifetime exploring, explaining and presenting truth, to the best of my ability. BUT -

You're truly AMAZING!

In all sincerity, I thank you for all your efforts, devotion and RESULTS! You're not only a great researcher and educator; you're a great inspiration!

[adamschroeder]

Kathy!!! You are a tremendous, positive, and passionate source of knowledge and information on the history and physics of electricity! I stumbled upon your videos, and I now plan to watch them all. Thank you so much for your passion and dedication and helping others love these things as much as you do. Cheers!