Viscosity and Poiseuille flow | Fluids | Physics

Viscosity and Poiseuille flow | Fluids | Physics | Khan Academy

Рет қаралды 327,525

10 жыл бұрын

David explains the concept of viscosity, viscous force, and Poiseuille's law.
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Пікірлер: 71

@jaymayhoi 9 жыл бұрын

Attempting to learn fluid dynamics and this is awesome, thanks. Makes me ponder how far reaching studying medicine is

@user-kb7oe5wr7c 7 жыл бұрын

In the exact same place right now, our textbooks are complete shit, but thanks to this I just started understanding it.

@ShadeOtree 7 жыл бұрын

الله يدخلك الجنه من أوسع ابوابها there are doctors gain more than 300 SR (nearly 80$ ) to teach us for an hour what you said in this video ! Thank you so much

@KatherinePierce_81 5 жыл бұрын

That isn’t much

@adityarajasekar5138 4 жыл бұрын

Ok dude... 😒

@ll-ht7mb 4 жыл бұрын

@@KatherinePierce_81 yep

@theDeathJoy 3 жыл бұрын

This explanation saved me where teachers failed. They keep redirecting me to formulas that are of no use and refuse to give a greater in depth explaination... So sad that college tuition is being wasted like that.

@nellvincervantes6233 3 жыл бұрын

I relate. Some schools are scam. 😅

@alialobaidy4610 5 жыл бұрын

I will name my first born after you. Also, someone just prayed for you to go to paradise in Arabic. This video literally creates world peace!

@mahimapasricha6388 5 жыл бұрын

I m in love with your teaching.. U taught so nicely thanks. ~a new fan and subscriber

@yuta2349 4 жыл бұрын

This was really helpful. Well explained :)

@heiheihei60 6 жыл бұрын

The explanation is so clear, and interesting

@OiynsoftCorporation 5 жыл бұрын

10:50 draws that smile 😂

@taylorneill2687 5 жыл бұрын

Amazing video, best Ive found thanks

@s5960 9 жыл бұрын

Brilliant, no idea why this video has so little views

@majdal-awar752 2 жыл бұрын

Amazingly explained!

@zamramumthaz1428 6 жыл бұрын

Incomparable explanations awsome.....

@sushanchamrugurung229 7 жыл бұрын

it's awesome ..... better than textbooks

@ruirodrigues3596 7 жыл бұрын

ofc its better than textbooks thats why teachers exits. Now the majority of uni teachers are people without the gift of education and with 3 phds so they tend to complicate even the most simple shit.

@kimanhoanthi117 4 жыл бұрын

literally. i couldnt understand a thing from my textbook so I had to come here.

@user-le2wu4yl7w 4 жыл бұрын

Very good example and explanation for understanding. Thank you

@anshulbirwal5788 5 жыл бұрын

It helped me a lot ✌

@antalenej3885 2 жыл бұрын

Thank you for this amazing video helped me a lot ❤

@2175Wook 7 жыл бұрын

A Fluid Mechanics problem that I'm trying to work out. A viscometer of the Redwood type has an oil-containing cylinder 4.75cm in diam and an agate tube 0.17 cm in diameter and 1.2 cm long. The oil surface, when flow starts, is 9 cm above the outlet from the agate tube. To allow for the sudden contractions at entry to the tube, the effective length of the tube may be taken as the actual length plus the tube radius. Making allowance for the decreasing head of oil, the viscous resistance through the tube, and the KE (kinetic energy) of discharge, calculate using arithmetical integration, the time required for 50 cm3 of an oil of viscosity 0.5 poise and specific gravity 0.92 to flow through the viscometer. How do you find the time? From this question, I have tried to use quadratic equation to solve for v, but it is proving more difficult than I thought

@abhinavpa7688 5 жыл бұрын

Very helpful thanks😍

@abdulmuizadegbindin3520 7 жыл бұрын

excellent video

@xxxx-xs5vr 7 жыл бұрын

you are amazing thank u so much

@bohdansenchyshyn9598 5 жыл бұрын

Nice. Excellent!!!

@yazandouleh9088 8 ай бұрын

Highly appreciated, thank you so much

@salmagamal5676 5 жыл бұрын

LIFE SAVER as always

@sophmiester 7 жыл бұрын

thats a dope box brah

@deviprasadpandey8518 2 жыл бұрын

Thanku so much sir you and your way of teaching is just amazing

@Kencan254 6 жыл бұрын

In MCAT, is the Poiseuille formula provided?

4 жыл бұрын

perfect.

@debangana9964 7 жыл бұрын

This guy, whoever he is, is great 😂😂😂

@lystfiskerlars 6 жыл бұрын

It's Rick

@twominuteanaesthesia 2 ай бұрын

Good stuff

@vAman00 7 жыл бұрын

I love your way of teaching 😭😭😭😭😭💓

@paoisaacleo882 8 ай бұрын

Thankyou

@skilifavas4016 5 жыл бұрын

Someone give this guy Money

@ashu.tosh_kumar11 4 жыл бұрын

Please can you write back me or give me ling of this question 👉on the view of viscosity and type of flow explane flood

@dhruvparmar4061 3 жыл бұрын

How we can consider fluid that is in contact with pipe is stationary?

@RhodesW 6 жыл бұрын

If you play it on 2x speed the mannerisms of speech sound like Rick from Rick and Morty

@amazeed8532 3 жыл бұрын

HAHAHA

@dontarobta4439 6 жыл бұрын

Whats the formula for viscosity in a newtonian fluid?? How do we "ignore" the "v" thats already present in the formula???

@saramohamed.8403 3 жыл бұрын

Try watching "why is ketchup so hard to pour" by TED ... it is kinda helpful with this speed matter

@ushasri2462 6 жыл бұрын

why did u consider velocity as speed in unit? Only that portion is not understood..same thing done in the book.

@leeeeni 3 жыл бұрын

Is the first flow called Couette-flow?

@MikeSmith-ej4zv 6 жыл бұрын

How would n not depend on velocity when n=f*d/A*v?

@davidkippy101 6 жыл бұрын

Mike Smith Because F is also in the equation, and when v changes, so does the force, which compensates for the change in velocity.

@nicholasturo-shields6477 6 жыл бұрын

The viscosity is generally a material property, depending on the temperature and other relevant state factors. Whether you pull fast or slowly does not change this material property. (This is only true for Newtonian fluids. Non-newtonian fluids act differently and are really cool. I suggest you look up videos on them)

@saramohamed.8403 3 жыл бұрын

Try watching "why is ketchup so hard to pour" by TED it explained this speed thing

@tecnicaltecnical4356 7 ай бұрын

There isnt in your videos translated in turkish can you add?

@faizagha2362 6 жыл бұрын

Wouldn't the viscous force be equal to the force applied because Newton said opposite and equal reaction to an action? Please can someone explain me that why can't we just say that the viscous force is equal to the force applied to the lid.

@faizagha2362 6 жыл бұрын

And please if I have left some basics don't mock me just answer me

@Drew88317 6 жыл бұрын

Equal and opposite reactions wouldn't resign every action to inaction, that is to say things can still move and not be stopped by the so called opposite force. Assuming the edges of the box were frictionless you could determine to a decent degree the viscosity by applying an increasing force to the plank and seeing at what point it began to move. If we do in fact know the coefficient of friction between the edges and the plank then we can estimate the viscosity by looking at the rate of deceleration when the box is full and when it is empty. The opposite force in this case is that the water pushes back, but more of the water will be pushed forward in the plank's direction. TLDR: We know the forces aren't equal because the plank is moving. The breaking point between where it begins to move and is stationary would be an equal force to the viscosity.