Denis YW Yu
Denis YW Yu
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What is special about this Escher picture?
Check out the symmetry elements in this Escher picture
มุมมอง: 160

วีดีโอ

How many balls are in the container?
มุมมอง 94ปีที่แล้ว
Check out the little secrets about invisibility
Smart windows on airplanes
มุมมอง 171ปีที่แล้ว
Learn how an electrochromic window works in this video
Why is the sky blue? And why is the sun reddish at sunset?
มุมมอง 206ปีที่แล้ว
A simple explanation on why the sky is blue and related phenomena
The Mysterious Can
มุมมอง 55ปีที่แล้ว
What do you think causes the supernatural phenomenon
How much thermal insulation (R-value) is a material?
มุมมอง 60ปีที่แล้ว
See this video for information about heat conduction, thermal insulation and R-value
Can you tell the difference between sunrise and sunset?
มุมมอง 18Kปีที่แล้ว
In this video, I will discuss about the difference between sunrise and sunset
How hot is a dolsot bibimbap?
มุมมอง 496ปีที่แล้ว
Find out how hot a Korean stone pot rice is and how long does it take to cool down.
What is the energy efficiency of a gas stove and what are the losses?
มุมมอง 1Kปีที่แล้ว
Experiments to estimate the energy efficiency of a gas stove, to understand the losses, and also to study the effect of a pot cover
Convection - how much heat is carried away?
มุมมอง 852 ปีที่แล้ว
A simple experiment to estimate convection heat transfer coefficient
Maillard Reaction
มุมมอง 872 ปีที่แล้ว
Learn about how food is charred to give us great taste (student video competition - gold award)
DIY watermill
มุมมอง 822 ปีที่แล้ว
Let us make a DIY watermill and see how it works
Reducing radiation with shiny surface
มุมมอง 1152 ปีที่แล้ว
See how effective is the reflective coating on reducing heat transfer
How does a dehumidifier work?
มุมมอง 34K2 ปีที่แล้ว
Learn how a dehumidifier works and also its energy efficiency in this video
Understanding psychrometric chart - advanced
มุมมอง 2672 ปีที่แล้ว
This part of the video explains the specific volume, wet bulb and enthalpy lines on the psychrometric chart
Understanding psychrometric chart - beginner
มุมมอง 6192 ปีที่แล้ว
Understanding psychrometric chart - beginner
Measuring humidity with a sling hygrometer
มุมมอง 2262 ปีที่แล้ว
Measuring humidity with a sling hygrometer
Skin effect and proximity effect - how they change resistance of wires
มุมมอง 13K2 ปีที่แล้ว
Skin effect and proximity effect - how they change resistance of wires
Body Fat and Electrical Resistance
มุมมอง 5112 ปีที่แล้ว
Body Fat and Electrical Resistance
Reactions of candles
มุมมอง 592 ปีที่แล้ว
Reactions of candles
Is your hand sanitizer at risk of fire?
มุมมอง 542 ปีที่แล้ว
Is your hand sanitizer at risk of fire?
Wireless charging, induction and transformers
มุมมอง 2412 ปีที่แล้ว
Wireless charging, induction and transformers
Zones Of Combustion of a Candle
มุมมอง 842 ปีที่แล้ว
Zones Of Combustion of a Candle
Science of cooking
มุมมอง 562 ปีที่แล้ว
Science of cooking
Holding fire without burning yourself
มุมมอง 1062 ปีที่แล้ว
Holding fire without burning yourself
Understanding inductor and inductance with demonstrations
มุมมอง 3402 ปีที่แล้ว
Understanding inductor and inductance with demonstrations
What is soot?
มุมมอง 4.9K2 ปีที่แล้ว
What is soot?
The Science of Fireworks
มุมมอง 1062 ปีที่แล้ว
The Science of Fireworks
What online lectures were like during COVID-19
มุมมอง 1133 ปีที่แล้ว
What online lectures were like during COVID-19

ความคิดเห็น

  • @rebeccagrey606
    @rebeccagrey606 11 วันที่ผ่านมา

    Basically turn on your air conditioner

  • @DaveMattingly-i7v
    @DaveMattingly-i7v 27 วันที่ผ่านมา

    Lyerys 😢

  • @geethikaisurusampath
    @geethikaisurusampath หลายเดือนก่อน

    Thank you for the effor you put into the video

  • @rezyousuf4954
    @rezyousuf4954 หลายเดือนก่อน

    What number should I programme humidistat button for a damp room?

  • @محمدمحمد-خ5ع2ص
    @محمدمحمد-خ5ع2ص หลายเดือนก่อน

    Thanks

  • @rafaelfonte11
    @rafaelfonte11 หลายเดือนก่อน

    Hi, thanks for the video. What is the voltage of the ultrasonic membrane?

    • @denisywyu7864
      @denisywyu7864 หลายเดือนก่อน

      Hello. It is not clearly written what is the voltage of the ultrasonic membrane, but the AC adaptor has an output voltage of 24V, so most likely it is 24V

  • @88BlueKeys4U
    @88BlueKeys4U หลายเดือนก่อน

    Very nicely shown and explained, interesting math and charts, thanks! Yet MY OWN cheap China humidifier puzzles me: it consists of two thin 15mm diameter ceramic wafers with centrally mounted metal membranes. Apparently a high (108kHz?) vibration is induced by the piezo effect. The bottom ( and NOT the top!) speaker like metal sheet has many tiny 5um holes. These seem to generate the cool mist visible above the SOLID (no opening AFAIK!) MEMBRANE on top of this diffuser. A wick feeds the bottom punch-hole sheet with water. How does the water get from in between these two thin metal sheets to the top surface, escaping the speaker-like membrane?? If the TOP membrane had these 5000+ holes (through a microscope they look odd, probably LASER burnt?) I'd understand the principle, but the switched order of these metal sheets puzzles me endlessly. These 50c atomizer plates are not very reliable, yet they do generate a quite impressive mist at a really low power: less than 1W feeds the circuit board, the activator membranes and the LED illumination. Of course this small scale device does not really change the room climate, but with a little fragrance added it creates a neat aroma in its vicinity. Just HOW the "speaker" gets access to the mist underneath it's top membrane escapes me..just like the mist..

    • @denisywyu7864
      @denisywyu7864 หลายเดือนก่อน

      Thank you for your comments. It is hard to tell without photos how the Chinese humidifier works, but my guess is that maybe the water goes in by capillary action

    • @88BlueKeys4U
      @88BlueKeys4U หลายเดือนก่อน

      ​@@denisywyu7864 third attempt, as Google deletes my replies within seconds (the digital age is coming to its mindless AI end..).. Thanks! It is obvious that the bottom metal membrane with its thousands of tiny holes will generate a mist of droplets when oscillating at high frequency, as it is in contact with the moist wick underneath. Yet the mist escapes on TOP of the upper (unpunched) membrane with its speaker-like solid dome. I can even see the tiny droplet streams in the mist with my myopic eyes. They seem to come THROUGH the SOLID TOP MEMBRANE, which makes of course no sense. Somehow the 'atomized' moisture must crawl around the cave between the two metal sheets along its outer rim (15mm diameter, held by a rubber ring), reach the top dome and get shaken off it by the oscillation. Magic at work. You can buy a bunch (3) of these atomizers with all the electronics, switches and LEDs for US$3 at AliExpress, or thousands for US$0.20 each at AliBaba. Fascinating stuff. I could fix my humidifier by replacing the ceramic oscillator element; strong mist is generated again. How long? Will the added aroma oil clog the 5um holes soon, certainly a risk. I already use distilled water, to avoid any mineral clogging of these elements. I took photos of my defective unit with an old digital microscope. The miniscule 5um holes are impressive to look at, in comparison of a stamp print and a human hair. Since my attempt to publish a link yielded in the removal of my reply (thank you, Google, for nothing!) here another one at "App""Box""COM" add this string by replacing the '-' with '/': -s-deqtsjt77vykpnfhn4d20hq834m070at-file-1663152839535 There is a lot to be found on YT about these humidifiers, your clip is the most comprehensive and scientific one I could dig up. Hence my contribution here. Thanks!

  • @lester9143
    @lester9143 2 หลายเดือนก่อน

    as expected bro is asian

  • @Rithysen85
    @Rithysen85 3 หลายเดือนก่อน

    b looks 9pm 8pm 7pm 6pm 5pm backwords 2:52

  • @nightmarejungle5871
    @nightmarejungle5871 3 หลายเดือนก่อน

    thanks good video

  • @TheSecrecyOfFrequency
    @TheSecrecyOfFrequency 4 หลายเดือนก่อน

    At 4:19 Did you mean to say Copper "Rod" not "Tube" because a tube is also hollow, which is what I thought was what made a Heat Pipe a heat pipe?

    • @DVCH_YT
      @DVCH_YT 4 หลายเดือนก่อน

      A heat pipe has a little bit of water in it so the water can evaporate and conduct the heat faster

  • @turel528
    @turel528 4 หลายเดือนก่อน

    That's a really good explanation. Thank you!

  • @alexengineering3754
    @alexengineering3754 4 หลายเดือนก่อน

    I did not know that proximity effect is so evil. That would explain, why some inductors perform so poorly even though the wire is smaller than the skin depth. Thank you!

  • @benmiller3358
    @benmiller3358 5 หลายเดือนก่อน

    Aren't you forgetting the LED in you watt usage calculations? 9.7-0.6-[LED draw]

    • @denisywyu7864
      @denisywyu7864 5 หลายเดือนก่อน

      thank you for the comment. The weight measurement was done with the LED off.

  • @sweetb4thesee
    @sweetb4thesee 5 หลายเดือนก่อน

    That can’t be true about the dust. I live on the ocean. I believe it’s because of the glare of the water from the ocean.

  • @Joe-rk1bb
    @Joe-rk1bb 5 หลายเดือนก่อน

    Very stupid experiment. Why did you include water evaporation??

  • @DontFuckWitDreDay
    @DontFuckWitDreDay 5 หลายเดือนก่อน

    Excellent sir

  • @brittanymwancientlight
    @brittanymwancientlight 6 หลายเดือนก่อน

    🌌

  • @goiterlanternbase
    @goiterlanternbase 6 หลายเดือนก่อน

    The main difference is the size of the condensing unit. Scale it up to much and you only get cold air, without noticeable condensation.

  • @blakeeiu
    @blakeeiu 6 หลายเดือนก่อน

    When the coils are close, the magentic field of each individual wrap has an affect on many neighboring individual wraps. When the coil is spread, the magetic field only affects the closest neighbors. See inductive choking.

  • @krish2nasa
    @krish2nasa 6 หลายเดือนก่อน

    Informative. Synthetic fuels almost eradicate the soot from its combustion. Thank you very much.

  • @krish2nasa
    @krish2nasa 6 หลายเดือนก่อน

    Excellent explanation. Thank you very much.

  • @gdehssalto8175
    @gdehssalto8175 6 หลายเดือนก่อน

    amazing thx u!

  • @matthewedwardhall
    @matthewedwardhall 6 หลายเดือนก่อน

    Wow, I guess them perfectly just from the feel.

  • @FratilaRadu
    @FratilaRadu 6 หลายเดือนก่อน

    Is AC resistance (skin or proximity effect) increased with higher currents ?

    • @denisywyu7864
      @denisywyu7864 6 หลายเดือนก่อน

      this is a good question. I think the skin effect and proximity effects affect the area of the wire that can carry a current, which in principle does not depend on current. However, in reality, higher current means that there will be more heat generated, and so the temperature of the wire will increase, and resistance is temperature-dependent (usually higher resistance with higher temperature)

  • @hallkbrdz
    @hallkbrdz 6 หลายเดือนก่อน

    Thank you for this simple but effective demonstration. I had been studying skin effect for coils I am making, but was puzzled why litz wire was specified with a much smaller area wires for a frequency than the skin area alone would suggest. I believe this must be due to minimizing the proximity effect.

    • @denisywyu7864
      @denisywyu7864 6 หลายเดือนก่อน

      Thank you for the comment. I think litz wire needs to account for the proximity effect as well, so they are thinner

  • @aleximorin
    @aleximorin 7 หลายเดือนก่อน

    Very nice video I was impressed

  • @ui9kq2xa5c
    @ui9kq2xa5c 7 หลายเดือนก่อน

    The sky at sunrise appears red and the sky at sunset appears yellow. If light is more scattered in the evening, shouldn't the sky be red rather than yellow?

  • @CristobalAshton
    @CristobalAshton 7 หลายเดือนก่อน

    Thanks Denis very informative

  • @wrefk
    @wrefk 7 หลายเดือนก่อน

    This was great.

  • @NJ-md8uu
    @NJ-md8uu 8 หลายเดือนก่อน

    I want you to be tutor for my son

  • @smferreiro2610
    @smferreiro2610 8 หลายเดือนก่อน

    Superman may not see temperature differences, but he may see that one of those "rods" is actually a pipe!

    • @denisywyu7864
      @denisywyu7864 8 หลายเดือนก่อน

      thank you for the comment. Sorry, I forgot to clarify that both of the rods are pipes, one without water inside and one with water inside.

  • @allemieux3977
    @allemieux3977 8 หลายเดือนก่อน

    Great video. On to Part 2.

  • @SteveDavis-je4bg
    @SteveDavis-je4bg 8 หลายเดือนก่อน

    I’m looking for an efficient way to create clouds in the sky. Could this principle be used?

    • @denisywyu7864
      @denisywyu7864 8 หลายเดือนก่อน

      I guess in principle, you could, but you need a water source to start out with. The ultrasound turns the water into water droplets. The other possible way to create clouds in the sky is to do what the airplane does in cold wet days (contrails) where the steam from the engine condenses in air to form cloud trails.

  • @markcod100
    @markcod100 9 หลายเดือนก่อน

    If you seal the cup / put a lid on and had the heat pipe go through the lid, would the heat pipe cool down the water to room temperature? Would that happen fast?

    • @denisywyu7864
      @denisywyu7864 9 หลายเดือนก่อน

      yes, the heat pipe will cool down the cup faster, as it conducts heat out of the cup faster

  • @YippeeKayay-xs8it
    @YippeeKayay-xs8it 9 หลายเดือนก่อน

    Just check if PM or AM and you'll know the answer.

    • @damonsonnier34
      @damonsonnier34 8 หลายเดือนก่อน

      The point is to tell the difference without using any clocks. Mainly if you are ever out in the wilderness or forests.

    • @omnacky
      @omnacky 8 หลายเดือนก่อน

      @@damonsonnier34 yes how would you ever identify sunset vs sunrise in the wilderness without a clock

    • @omnacky
      @omnacky 8 หลายเดือนก่อน

      besides remembering if it was dark outside 30 mins ago

    • @damonsonnier34
      @damonsonnier34 8 หลายเดือนก่อน

      @@omnacky Because campers and hikers do not always fall asleep at nighttime.

    • @michaelkyles-villalobos551
      @michaelkyles-villalobos551 7 หลายเดือนก่อน

      Hahahahahaaa. Too funny. Great joke.

  • @RunnerPack
    @RunnerPack 10 หลายเดือนก่อน

    Excellent video! If you feel like it, please do one about the humidifiers that have the piezo transducer at the top of a wick sticking out of the water (or link to it if you already did one). Thanks!

  • @michaelgoodson5255
    @michaelgoodson5255 10 หลายเดือนก่อน

    This is great!

  • @HalfWarrior
    @HalfWarrior 10 หลายเดือนก่อน

    The earth is not rotating.

    • @stevenchalos4829
      @stevenchalos4829 10 หลายเดือนก่อน

      ? Curious

    • @Nico_com_c
      @Nico_com_c 9 หลายเดือนก่อน

      Prove it. No balls.

    • @tek87
      @tek87 7 หลายเดือนก่อน

      Everything i thought was true is a lie??

  • @hermanfourie66
    @hermanfourie66 10 หลายเดือนก่อน

    Thanks for creating this vid; the explanations are very intuitive and easy to follow :) .

  • @ahmednor5806
    @ahmednor5806 11 หลายเดือนก่อน

    🙏🙏🌹🌹

  • @blunt3862
    @blunt3862 11 หลายเดือนก่อน

    Good explanation 🙏🏽👍🏽

  • @sayanasasidharan16
    @sayanasasidharan16 11 หลายเดือนก่อน

    Denis y w.. we have the same humidifier. It was working fine but suddenly when we adjust the timing of humidifier and as it starts the small fan… the motor stops its own. Why does this happen? How can we fix this humidifier back to normal?

  • @claireboulton8725
    @claireboulton8725 11 หลายเดือนก่อน

    Very good videos the others are so dumb and don't explain

  • @zot2698
    @zot2698 11 หลายเดือนก่อน

    OMg! such a great video!

  • @sam5992
    @sam5992 11 หลายเดือนก่อน

    Out of all the dumb, disastrously long videos on the internet about humidifiers, this was the best one, not dumb at all, and was the most informative with actual testing and data. Thank you for cutting through the stupidity. What a breath of fresh air.

  • @JAKESMITH-tt8nm
    @JAKESMITH-tt8nm ปีที่แล้ว

    Perfect. Answered all the questions and then some.

  • @davidzaharijevic5681
    @davidzaharijevic5681 ปีที่แล้ว

    Great video

  • @MegaWavesMusic
    @MegaWavesMusic ปีที่แล้ว

    This was really well presented 👍🏽 thank you! The Smashing Pumpkins song "Soot and Stars" brought me here ✌🏽

  • @plazmatest
    @plazmatest ปีที่แล้ว

    love it