Young Laplace Equation

An introduction to the Young-Laplace equation. One of a series of videos using lightboard technology developed at Imperial College London. I would like to thank Ollie Inglis, Hywel Jones and Lekan Ladipo from the Digital Media Centre in the Faculty of Engineering at Imperial College London for their help producing this and the other lightboard videos.

[@anubhavarora3282]

Sir your way of explaining is truly fabulous. I am grateful to you for providing such a quality content

[@fredkester6130]

I totally agree, thank you!

[@JohnParra-u2o]

Finally I understand the basis behind the 2σ/r. Thank you for sharing your knowledge, Professor.

[@adampax]

Masterful work to explain mean curvature intuitively in less than 15 minutes!

[@笠峰倪]

Your explanation is clearer and more understandable than the one in Landau's Fluid Dynamics. Thank you.😁

[@BoffyBlunt]

Many thanks - rare praise indeed!

[@Fawad.ANizamani]

OH MY GOD you are back

[@IndiraYessenaliyeva]

Crystal clear, thank u 🙏

[@trishanuagarwal9220]

Very beautiful proof sir Thank you for explaining

[@pizzalove4693]

Very nice explanation Thank you for such quality content

[@DANGJOS]

You make it look easy, thanks!

[@agamjain9138]

Thank you sir❤

[@cooltech9161]

isn't a force being applied by the interfacial tension? So why have we not taken the pressure exerted by this force in the derivation?

[@BoffyBlunt]

Yes this is correct but it is easier to derive the equation using an energy balance. Instead we do use a force balance to derive the Young equation.

[@zq88]

Hello, Professor. Thanks for your video! Can you explain how to determine the curvature sign? My understanding is that if the curvature center is in the denser phase, then it is positive. Is that right?

[@BoffyBlunt]

I think you have this the wrong way round. We define the capillary pressure as the difference in pressure between the less dense phase and the denser phase, then positive curvature is when the less dense phase bulges out into the less dense phase (think gas and water).

[@zq88]

​@@BoffyBlunt Thank you sir! I think I've got it.😃

[@manikmehta2090]

❤️❤️thanks sirr

[@fabriziodimeo]

I suppose there's an error: dA isn't equal to alfa*beta*(r1+dr)(r2+dr) but it's equal to alfa*beta*(r2dr1+r1dr2). right? :-?

[@BoffyBlunt]

In the video A + dA is the term you mention, so dA is as you say with dr1 = dr2 = dr.

[@fabriziodimeo]

@@BoffyBlunt thank you

[@User-Tal1951]

Hi I need to ask something. How to reach you? Thanks

[@BoffyBlunt]

You can email me at [e-mail]

[@coldchickennoodles5575]

I still don't understand the equation, can someone explain pls

[@BoffyBlunt]

What specifically would you like help with? I can try to clarify points that you are confused with.

[@coldchickennoodles5575]

@@BoffyBlunt Thank you so much for answering. I just find the 'dv' part in the first equation you presented slightly confusing and the V=4/3(pi)r^3

[@BoffyBlunt]

@@coldchickennoodles5575 The dV comes from work - the work done from basic physics is PdV where P is pressure and dV is the change in volume. The equation V - 4/3(pi)r^3 is the equation for the volume of a sphere in terms of its radius r.

[@noodles8439]

I understand everything except that the professor can write backwards.

[@stanleynio]

Fr

[@TheJugx]

Mirrored...

[@SatishNatarajan]

He is writing with his left hand and it is mirrored.