Good april fool's day video considering windmills are giant fans, and they are responsible for all the wind.

"uploading a serious video on april fool's is a fool's errand" - Tom Scott

The best April Fools joke is one that makes you think you're being fooled when in fact you aren't.

I have actually learned it in college last year. You used two minutes to explain two whole lecture's knowledge. You are a legend.

For the whole time I kept thinking 'you are hiding the april fool's part way to well, people are going to actually believe it if the rest of the video is making too much sense'

Actually had to study this in one of my majors while studying Mechanical Engineering back in college and this video summarizes and explains this stuff really well!

Fun fact: All minutephysics videos are so awesome, it only feels like a single minute when you watch. It’s the most enjoyable kind of time dilation.

I'm an average guy with no real academic degree or whatever...but... my thirst for understanding physics grows with every video i see from this amazing channel.. Thank you sir.

This is something I had to learn during my Aerospace studies regarding propellers. It's the same, but the other way around.

Thank you for keeping me from not learning.

He is the one of those who uploads video which I can't see in 2x.

Been following your channel since my high school physics teacher introduced the class to your videos over 10 years ago… every week we got to spend the first 2 minutes of class enjoying your videos… glad you’re still making great content

I appreciate that nod to the complexity and the book pages at the end.

This couldn't have come at a better time. I'm doing my final year dissertation right now and a section of it is about windmills and energy extraction. This helped me a lot with understanding it better.

The problem with windmills is that when the wind blows in the opposite direction the blades turn the other way and suck electricity out of the grid.

This brings back memories about how I found out about this figure. When I was elementary school (15+ yrs back) I really liked to make windmills from wood wings (like 1,5x5 cm wide wood-piece and with knife/polishing making somewhat triangle from that with smooth "catching" edge and rounded back for light-weight and more "efficiency"). Three best examples had 3 wings (~0,8 m long each), 3 wings (1,1 m each) and my best - 5 wing (1,2 m each) design that worked at lower speeds than 3-wing (it was located low to ground with uneven terrain/trees around so only 1 lower wing (with 120 degrees between) had trouble to keep speed up and it lead to vibrations. 2 lower wings (with 72 degrees between) solved issue and it was smooth and worked as expected. And it was this time when got to figures how wind speed impacts power (not sure how precise but from that time used m/s^3 = W/m2 formula whenever wanted to know how much power windmill actually can extract - and that "nominal" power was based on ~9 m/s windspeed). And how efficient it can get (figure in video) etc.

Wind...Mill? Behold, sciences latest triumph over wind power - the Windlathe!

glad to see you posting again great video

So a legit video. Apparently cut content - nice! Thank you.

A corridor crew video from 2016 brought me to this channel. Thanks Wren.

Betz's law! Finally I know where that 'magic number' comes. It's quite familiar for mechanical engineering students who studying fluid dynamics

I learned more from this channel than all my online classes combined.

I was hoping for an April Fool's joke

Brilliant! I was gonna make a video about this for my Power Systems students, but now I just have to give them the link to this video!

Great content as always! Though the "solution" in the title actually had me hoping that we were able to surpass the 59% limit! Looking forward to your future videos.

Awesome explanation on Nebula! More please, my fellow Physicist!

Amazing video!

might seem complicated at the first time to me, but it's well explained when replayed. I didn't know I can catch up Betz's law in 6 minute. Thank you

Wow sir, how did you make this video, without you actually showing yourself onscreen, in the sense your hand!?! Beautiful !

Ah some minutephysics😃

This is a good explanation of the math in Betz's paper! Do you think you could do a video on Betz's paper on multiple rotors?

Please go more in-depth on the energy differences of drag based windmills vs lift based windmills

I want to thank you for not uploading an April fools video

minutephysics: Posts a new video. Almost Everyone: Go straight to the comments section!

Didn't know I needed to know this, but I'm a fan.

i'm kinda disappointed that i learned something on april 1st

Windmill Energy Conservation, 56.25% HD TV 16:9 aspect ratio, 56.25% We need windmills to power our TVs.

- Making video to explain interesting PrObLeM then do it with the speed of light is a pRoBlEm itself . - Compressing information to produce a short video that sAvE TiMe made me pause/back a lot in order to catch up , which wAsTe my time any way . - It is not about given an information , it is about how to present it . ~ keep up the good work , thank you

I'm already a curiosity stream and nebula subscriber, it would be really cool if you gave us a direct link to this video on those platforms, so I can pop over there and see that video without having to search and find it

I can't make a joke yet, the video hasn't even started

thought it was gonna an Aprils fools video and was waiting the entire video for the nonsense to start

Great woooork 🥳🥳🥳 Thank you 💜💜💜

The most you can mill from wind is 100%. With a type of mill called sail.

This makes me really wonder, if humanity completely switches to wind power, would that actually influence the climate through slowing down winds???

0:54 , 1:36 , 1:40 There's an error : it's not "wind volume" but "wind section" or "wind area" or "closed surface" in mathematics. (in fact, saying "volume" is absolutly wrong, volume per second is actually constant, by conservation of mass) Plus, you showed why speed at the mill was 3/4 of in speed but not why it means 3/4 of wind in SECTION(!!!), on a slide that titles "conservation of mass" but doesn't use it. Explanation : flux formulas : flux (unit/s) = j (unit/m².s) . Surface (m²) j (unit/m².s) = density (unit/m³) . velocity (m/s) ( "j" is "flux density" but I wanted to keep one word per variable) In the case of a windmill, air compression is negligible, so there is no noticable variation in density. We'll consider density as a constant D. Thus, flux = D . velocity . surface For a given flux F, in other words when you conserve mass (or electric charge or "unit" of any quantity), an increase in velocity means a proportionnal decrease of surface. Proof : F = D . v(a) . S(a) = D . v(b) . S(b) or more interestingly v(a) . S(a) = v(b) . S(b) or in an other form v(a) / v(b) = S(b) / S(a) if v(mill) = 3/4 . v(in) then, v(in) . S(in) = 3/4 . v(in) . S(mill) => divide both equation members by v(in) => S(in) = 3/4 S(mill) ◻ PS : at 1:05 , 1:18 , "as much wind to pass" is given by wind section S(in), not wind velocity v(mill). Yes, it's the same proportion, but mixing surfaces and velocities has no sense... It's like saying a bottle of water has a mass of 1L. Yes, 1L of water = 1kg. But 1L is not a mass!!! Don't mix speed and cross section even if you fall on good numbers.

Very short, very interesting! I feel like some people may have gotten lost cause of how fast it was, but I was fine (granted I'm a physics and science ed major...)!

It'd be very nice and handy if the Nebula video was linked in the description.

Great video, thank you. Could you, maybe next time, also share references to the papers/books you are using in the video? Chreers

I was partly wondering if this would be about how much grains they could mill, and partly how much they should be allowed to tumble around over the countryside (not on the post, much like a big loose wheel).

In the first clip of the outflow pipe moving up and down the side of the reservoir, you say that you can lower the water without slowing the flow, but wouldn't lowering it increase the pressure and make it flow out faster?

I can't believe this video is not just a bunch of hot air.

I wish the winds around the region I live could be reduced a lot.. here we even gave a local name to the wind that hits this region of Spain.. It is called Cierzo and it is quite strong, a lot of windmills could have a lot of benefit from it and ease on the wind that hits the city.. haha that would be nice..

What i heard was: How much does windmill mill the wind when windmill mills the windmill and windmill slows down.

Hey the videos you make are dense packets of information and are awesome , but here you have just given the explanation for Betz limit right?then how is it a solution to windmill paradox? Or is it just a way of putting content related to April 1?

The best part is when I had to skip back several time before finally realising I still have no idea what is going on.

I liked the first title of "how much wind should a windmill mill"

“WINDMILLS DO NOT WORK TGAT WAY! GOODNIGHT!! “

I wish my physics lesson was this short and understandable

How many birds and bats can a windmill mill?

I actually knew it was about 60% because a friend of mine did a science fair project on it back in highschool (he mounted different windmill designs on top of a truck, it was pretty cool). But actually this number doesn't matter that much because windfarm windmills actually extract a lot less energy than this, partly because this works for single windmills but doesn't account for several windmills lined up behind each other.

Wow, someone gave a thumbs down before it's even started!

There was a point where I think you could elaborate more at: when saying that lower speed means the windmill extracts energy from "less" wind, I had to think pretty hard to realise you meant "wind of constant density"...

I had never thought about wind volume… that's wild

All good points.

Can you make an updated version of your time travel video with endgame, dark and tenet time travel system?

Dam windmills... dam. I can't think of anything to add to this dam pun.

So in the city could a build have windmill floors basically windowless floors funneling air through, would that also help in reducing sway allowing some air to flow through instead of just crashing into.

This is called the Betz limit, named for the German physicist who published the mathematical proof in 1919. The magic number is 16/27.

Since he was not given credit in the video, the German physicist Albert Betz did the necessary research and math to calculate these limits.

Could you please make a video of how does a gear work or how does the engine work

Hearing "Three Fourths" just sounds so alien to me. We say "Three Quarters" the same way someone says "One Half". I hope no one says "One Twoths" or something silly like that.

The statement that the wind accomplishes half its deceleration before arriving at the windmill is only true when its Mach number is much leas than one. In my hometown of Lubbock, Texas, where wind speeds reach Mach 0.85 on a pleasant day and Mach 2.5 in nasty storms, your statement no longer holds.

@minutephysics I really want you to explain CT clamps on AC circuits. How can an RMS value give a direction on the current. Please investigate.

We need a video on the muon g-2 results

Cool, i miss this

Big fan from india

I figured it out after he said there is more in depth parts to this

Love From India🇮🇳❤️

Exact name for this is : Betz's law. From Albert Betz.

All these fractions started making my head spin 🥴

Putting duct would probably increase such efficiency and reduce bird strike

Title: Windmills Are NOT Like Dams Me: No shit

2 uploads in one week? From both Veritasium and Minute physics??

Can you link the nebula version in the description? Very annoying to have to navigate to it. Also annoying to find out there is an extended version of the video on Nebula at the end after I've just finished watching this version.

i just noticed a math thing and i’m wondering if there’s a reason for it. ex, 7x7 is 49 and 6x8 is 48. Add one and subtract one from each side of equal products and the answer is always one less than the equal products. Is there a math principle for this? an explanation video would be awesome!

I didn't notice the date, thought it would be a serious video...

a video on MUON G-2 experiment please🙏😀

I got dizzy and in the end "Of course that windmills are way more complex"

Do windmills have adaptive systems to deal with changing wind speeds?

POV: You're getting flashbacks of sitting in class and you're the only one who doesn't get it, because the pace is too fast for you

solution to a problem that I never knew existed

Forgive me if this is a dumb question, but why would we care about the efficiency of the energy extraction - i.e. isn't more energy farmed always better? Why do we care about per unit wind when there's an abundance of it, it's not like there's a problem with taking as much energy out of the wind as possible yeah?

Huh. I had no idea. I'll have to see your other video.

i don’t really understand anything he says, but it’s still hella interesting

I feel like I know less about windmills now than before I watched this video.

Please put a link to the extended Nebula version in your video's descriptions. It's pretty annoying to have to navigate to it (Nebula is slow...)

What are those scientific papers you cite/show ? Why doesnt the description mention and link those, such that we may have a chance to try to make those computations by ourselves? Im sure the math involved is intricate

So i got an important question i need answered. I read in a few pages that apparently either exists or will exist a type of computer that will run instead of on 2 stages, on and off, with 3 stages, on, off and in between, called quantum computer. If such thing is the case, could we use the principal of teleportation to transfer internet globally at the speed of light without cables? Could we do it with the internet as it is? I hope this makes sense

What's up with your fascination with wind mills??

Next: the Stirling Engine Paradox