chapter9GREG - Chapter9 SolidsandFluids StatesofMatter...

Info icon This preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 9 Solids and Fluids
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
States of Matter  Solid Liquid Gas Plasma ---this is  total BS . Liquids and gases  are not always distinguishable. What  defines a state of matter is its symmetry  more than any other one thing.
Image of page 2
Crystalline Solid Atoms order in a lattice (beautiful, no?) Faceting is a  sign of  microscopic  order Diamond
Image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Amorphous Solid Atoms are arranged  almost randomly, but  rigid if you push on it! Examples include glass  (SiO2) We don’t understand  glasses still,  random=difficult  in this  case
Image of page 4
More About Solids External forces can be applied to the  solid and compress the material When the force is removed, the solid  returns to its original shape and size This property is called  elasticity Generally we refer to a ‘rigidity’ to external  forces.
Image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Liquid Has a definite volume, No definite shape The molecules “wander” through the liquid in a  random  fashion The intermolecular forces are not strong enough to keep  the molecules in a fixed position A liquid is not ‘rigid’ to an external stress and the ‘random’  distribution of molecular position means it looks isotropic  from all directions. In a solid the symmetry is lower,  because there are definite crystal axes (it’s ‘lost’ rotational  symmetry). 
Image of page 6
Gas Has no definite volume, Has no definite shape.  What the book means here is that a gas can be  compressed, but water is mostly incompressable  (except at very high pressure). Molecules are in constant random motion Average distance between molecules is large  compared to the size of the molecules. This is the  major difference between a liquid and a gas.  They’re both ‘isotropic’ though.
Image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Mesophases Imagine now being crystalline in  one direction, but isotropic in the  plane perpendicular to it. This is  (one form of) a liquid crystal (=flat  screens).  Some rotational symmetry was lost. It is rigid to a force in one direction,  soft and squishy like water in  another Squishy this  way Rigid
Image of page 8
What ‘condensed matter’ physicists think  about phases really (magnetic example) A) The spins point randomly, like the  random positions of molecules in a  liquid, and the material appears  isotropic B)-E) the spins are no longer random, but  form one of a ‘zoo’ of magnetic orders  which ‘break’ the isotropic symmetry  to something with an axis.  ‘phase’ of matter, usually means a  different symmetry Modern ideas are challenging this  with other geometric ideas (topology)
Image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Types of Matter Normal matter (‘baryonic’)
Image of page 10
Image of page 11
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern