# Read about surfaces | 4 Discussions | Page 1

1. ### B Why don't solids always stick together?

Hi all, Something I've been wondering - why don't two solid surfaces always stick together when touching each other? As far as I'm aware there are five basic types of solids: Atomic solids: Frozen noble gases containing single atoms held together by London dispersion forces. Molecular...
2. ### I Variation of geometrical quantities under infinitesimal deformation

This question is about 2-d surfaces embedded inR3 It's easy to find information on how the metric tensor changes when $$x_{\mu}\rightarrow x_{\mu}+\varepsilon\xi(x)$$ So, what about the variation of the second fundamental form, the Gauss and the mean curvature? how they change? I found...
3. ### How do I parameterize these surfaces?

Homework Statement Parameterize ##S={ S }_{ 1 }\bigcup { { S }_{ 2 } } ##, where ##S_1## is the surface with equation ##x^2+y^2=4## bounded above by the graph of ##2y+z=6## and below by the ##xy## plane. ##S_2## is the bottom disk Homework Equations The Attempt at a Solution ##{ S }_{ 1...
4. ### Help please -- Problem of hydrostatics force in flat surfaces

Homework Statement Homework Equations The Attempt at a Solution I could know the pressure in point B If I calculate the heigh of pressure I got: But I don't know where is my free surface in the container 3, is it down?? I don't know how to keep doing it.....