This Weird Straw Effect | EVERYDAY MYSTERIES

Pubblicato il 4 lug 2019
When you look through a straw in water something strange happens as you move it up and down.
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Thanks to William Osman!
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Creator/Host: Dianna Cowern
Editor: Levi Butner
Research & Writing: Dianna & Imogen Ashford
Don Pettit footage: NASA


  • A water lens can be used for some interesting effects. For example, a little drop of water on the phone camera glass makes it work like a microscope. Of course, be careful since not all phone cameras are sealed enough to avoid the camera damage. The drop should be only in the middle of the glass.

  • In the early 80s I did some straw based activities but I used powder to prevent the surface tension at the end of it

  • So you are saying your super white teeth and white parts of your eyes are really red green and blue?

  • tHaT nOt VeRy VsCo Of yOu

  • Two questions: 1. Does it work with rubber or paper straws? 2. If you could make a straw so opaque that it prevents light from shining through, what effect would using the straw as a flashlight bring?

  • I actually know a guy who poked his eye out looking through a straw like that. He didn’t really poke it out, but he messed up his eye pretty bad. He couldn’t uncover it for weeks and he said that it was by far the most painful thing he has ever experienced; his descriptions of the experience make it sound truly horrible. Please be careful if you are going to do this!

  • Concave, convex..come on physics girl I know you understand and can use these words.

  • HIGH VOLTAGE TRAILS IN CO2 'FOG' Can you explain this at all please! It's crazy and would be so interesting!

  • and we are all gonna ignore that she's a Slytherin

  • 2:48 Concave... is the word you're looking for :)

  • concave/ convex lens formed by bubble of water formed at end of straw.

  • 3:57 “It has less adhesion. *Another... Word.* “

  • I wish I had a pretty, intelligent GF I could talk to about Science exactly like you

  • Are you self-conscious about using the right word because so many viewers are illiterate?

  • Ummm ur a slytherin?? Unexpected, really unexpected

  • Bulging up = convex; bulging in = concave (to remember concave think cave, it goes in).

  • So, does the lens effect only work while the straw is moving? What sort of effect happens when the straw is stationary? My brain is thinking that if the straw is not moving then the water would do the weird thing that it does and climb slightly up the sides of the straw forming a concave lens when it's not moving. Am I thinking about this wrong?

  • Really great video ! Thank you !

  • water lens that changes size

  • could you make a giant lens, by laying a plastic films above a ring and pouring water in it??

  • I tried the microgravity lens, but didn't have enough time before I hit the ground. ;-(

  • Did you try the big straw in a pool? Damn you are brave you use plastic straws be careful with them they are dangerous. You had to be a blast to hang around with as a kid.

  • Hmm... she likes beanies?`lol

  • If you seal your hands around your eyes while looking down in the water, you get prescription goggles! Try it.

  • Capillarity lenses effect fun! Convex & concave

  • well, the lens in your eye is cell based, which is water, but with a LOT of protein in solution (like hundreds of mgs/ml). This high protein concentration give the solution a high index of refraction, making a good lens material. The proteins are called crystallins, which are actually just house keeping proteins repurposed for lens development by evolution because they can exist at such high concentrations. Even more cool- the cells in the lens are super regularly packed, and the central cells get rid of all of their organelles, to increase optical clarity. Even MORE cool is that the refractive index isn't even uniform across, and the lens deforms ("accomodates") to focus on different distances. The visual system of vertebrates actually use two lens elements- the lens and the cornea, which is also super cool- how it arranges its collagen fibers to be clear, not opaque (like the sclera, which is white due to a different collagen arrangement). And even MORE cool is... oh. Wait. No one is even reading this. Derp.

  • An antonym of "bulge" is "dent". Works well enough when sticking to layman's terms.

  • Adhesion. Another... word.

  • Just don't poke yourself in the eye lol

  • Awesome

  • 0:59 someone please tell me what movie or show that scene is from

    • One of the "Pink Panther" films with Peter Sellers

  • So, the surface tension causes the water surface to make a lens. As you move the straw up and down, it actually will cause the SURFACE of the water in the straw to rise and lower. This is because the bottom of the straw is going to be at a different pressure due to it's different depth, and will raise the waters surface in the straw at depth, and lower the surface of the water in the straw when the submerged end is shallow. The difference between the two surface levels will change the focal length of the 'lens' and cause more or less magnification.

  • a liquid tension experiment :0

  • I had a really interesting experience once as a kid with this principle. I was floating upside down in the deepend of a pool. I exhaled and I have no idea how but a bubble got stuck perfectly over my eyes for a moment. My eyes were open and just for that moment I could see the bottom of the pool clearly, like wearing goggles, and beyond that magnified! I obviously couldn't stay terribly steady like this and the second Ii moved the bubble dislodged and floated to the surface and again the water was fuzzy looking with my bare eye. I wonder if you could recreate this experience somehow?

  • Why can you see through frosted glass when you stick a transparent adhesive tape on it? #everyday mysteries

  • Drinking with straw makes you drunk faster

  • I wonder: rainy clound often is black clound, why?


  • Good video but did such simple and obvious phenomenon really deserve so much wow¿ thx anyway

  • Could anyone tell me if straw size or lighting effects this experiment at all? Im thinking maybe i didnt have enough light lol

  • Makes me wonder if that is similar to a gravitational lens

  • Alcohol makes things look way better!

  • Like anti matter, dark energy, is there anything like anti gravity (I am asking this question because in universe everything has something opposite to it). I'll thankful to you if you answer this question.

    • Look up some of Nickolas Tesla's works, he theorized a form of this but it requires gravity to be a electromagnetic energy and not a force (extremely simplified), and also the theories associated with quantum gravity particle (Graviton) assuming gravity is a particle and has mass if observed. Both these theories contradict each other though if I understand then correctly.

  • YOU ARE SUCH FUNNY..great...

  • Inverted lens?

  • 2:22 *notices your bulge* Diana: uwu

  • Crazy revolutionary clip For that you need: -A clip without plastic -Two neodinium magnets (with the same shape and strong) -A very thin thread and not elastic (better if it's long) Procedure: Put the thread around the clip (the part with one edge) and then rotate a lot the clip (around 150-200 times) put the clip close to the magnet 1 (and starts spining) pull it back and put it close to the magnet 2 (and starts spinning faster) do it whatever times you want and it will go so fast, it creats a sound. I don't know why that's happends (Sorry for my english)

  • +1 for Pink Panther reference

  • the water tension is making a lense

  • This girl cracks me up! She kinda awesome. 😊

  • Concave convex

  • I'm not a physics expert by any stretch of the imagination. But withing the first 30 seconds I had figured out the effect through what I used to call 20 years ago, everyday miloisms! Suffice it to say, that even though I was never an A student for lack of ambition to be I always had a knack for understanding concepts and physical interactions both small scale and large-scale. I say all this to say where my appreciation and fascination for our shared joy comes from in regards to such small trivial observations.

  • "Surface tension" creates a CONVEX lens as the straw is pushed down into the water; a CONCAVE lens is created as the straw is lifted. Alcohol has little or no surface tension based on its solution dilution(i.e. 50% rubbing alcohol vs 70% or 90%). A product by Shaklee called "Basic H" breaks down the surface tension of water without adding color or changing viscosity; improving the ability of water to permeate porous materials which makes it great as an additive to laundry. This product, Basic H, would negate the lensing effect displayed in this video. Cool, huh?

  • I wonder if increasing the viscosity would make it easier for a larger diameter tube to have the same effect as with the straw?

    • What about water beads? And what if water beads were pureed into a thicker mixture to use with the larger tube?

  • Giant straw, a.k.a pipe. Nice.

  • Plastic straws are banned in our country 😭😭

  • Another, much drier, magnifier you can make is with your thumbs and forefingers. Put them together with a small opening between them. Get your fingers and eye really close to what you want to magnify, like letters in a book, and adjust the opening size. Voila, a magnifier.

  • Why would the water form a convex surface? Wouldn't gravity and cohesive forces prevent that? What am I missing??

    • Gravity is a relatively small force on something this size and the cohesive force or bond of the water molecules is stronger than the force gravity exerts, when the larger tube is used the overall surface flattens out due to gravity though at the very edge there will still be some small curvature due to cohesive forces.

  • Concave and convex lenses :) that's their name :-) Interesting effect, you could try to combine 2 different liquid and see if you can get an acromatic doublet !

    • I wonder if increasing the viscosity would make it easier for a larger diameter tube to have the same effect as with the straw?

  • Please make a video on parallel universes.