Physics 34 Fluid Dynamics (2 of 24) Viscosity & Fluid Flow: Stokes' Law

In this video I will introduce viscosity and fluid flow involving frictional forces between the molecules and the containing walls.

Next video in this series can be seen at:

[MiiMaker]

Finally, a video without an indian speaking.

[championakali]

So is Stoke's Law and Dynamic Viscosity formula the same thing? Or is it just by applying Stoke's Law, we can find the Dynamic Viscosity formula.

[clo]

@3.02 shouldn't the mass (of marble) = density (of marble) * volume (or marble)? But in the equation you wrote mass (of marble) = density (of marble) * volume (or liquid) ...

[asitpurohit]

I have a doubt, why buyonace force doesn't depend on depth? 2nd part suppose a body is there which float in surface, can it be possible to sink it, if we forcefully put it at a depth h, where the total force at the object by the weight of object + pressure of water above density * g* h, it is more than the buyonace force ( because buyonace force is constant at any depth)


W + density *g*h > buyonace force at the depth h, so it will stay inside, never will able to come to surface

[adamhedges]

when simplifying at the end why is the viscosity of the liquid divided by just one of the terms on the RHS and not the whole equation? My lecturer suggest it is the entire RHS that should be divided :/

[apoorvtrivedi]

SIR YOU ARE GREAT.I AM THANKFUL FOR YOUR GREAT WORK.WONDERFUL EXPERIENCE.
THANK YOU SIR.

[هاشمالطوري-خغ]

@Michel van Biezen Why stoks law work only on the small radius spheres ?\

[asitpurohit]

Is their any derivation of stoke law other than dimensions analysis, I think dimensions analysis less natural, it's like guessing work

[otiscarr]

How about Allen Flow? Also why R in capital, confusing me with Reynolds number.

[anupamdas]

sir, if we consider cylinder instead of sphere what will happen to the drag force Fd??? Will it be changed?? How, why and to what??

[anesmerazi]

sir, why does the spherical object keep sinking if the sum of the applied forces on it is equal to 0, shouldn't it stop moving ?

[matiasgaudenzi]

Great explanation, knowledgeable, explained in simple terms, and to the point. Keep them coming!

[Giovanni]

Shouldn't the Fd be called "Viscous Friction Force" rather than "Drag Force"? It gets confusing when comparing this video with the one about the Drag coefficient.

[milansekularac]

Very nice tutorial. A small remark: not sure if calling "mg" a "weight" is correct. A body can be weightless, while it falls in g field, but still the gravitational force mg is exerted on it. To have "weight" the body needs to be suspended on a rope, or siting on a table or so, in a g grav.field.

[samsarazara]

thanks sir! really helpful! Love your whole series of physics which helps me survive IB

[mphomajestic]

finally i can understand application of stoke law and concept, thank you

[charifaberkanekrachai]

at first i want to think you sir for this videos
and i have this question what if the pipe is horizontally positioned is the drag force stays the same( the same law )or it will be different please sir replay to my question as soon as possible thank you again

[HariAnantharaman]

Excellent .... Focused, concise and clear

[elensimanjuntak]

Thankyou so much sir to make this educational video! Really make me easier to understand about stokes law

[Descifrador]

Respected Sir...
I have a doubt that why Stokes law is applicable only on spherical bodies