L9 - Paramagnet - Pressure(1)

# L9 - Paramagnet - Pressure(1) - PH2103 Thermal Physics...

This preview shows pages 1–7. Sign up to view the full content.

PH2103 Thermal Physics Lecture 9: Paramagnet, Pressure Massimo Pia Ciamarra [email protected] SPMS-PAP-03-14 Textbook paragraph: 3.3; 3.4 (part) Discussion Forum

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

View Full Document
1. Paramagnet Entropy & Temperature 2. Mechanical Equilibrium Pressure Ideal gas Agenda
1. Paramagnet Entropy and temperature

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

View Full Document
Paramagnet At the microscopic scale, each atom/molecule can be seen as a little compass needle, that feels a torque that tries to align its magnetic dipole with the existing magnetic field, B. Absence of magnetic field Presence of magnetic field More in your Electromagnetism course
Energy Quantum mechanics → quantization of the magnetic dipole along the field direct. If only to states are allowed, we represent the dipole as an arrow parallel or antiparallel to the field. Applied magnetic field Representation of a two-state paramagnet As concern the energy: 0   Energy of a dipole: Parallel antiparallel E =±μ B

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

View Full Document
Energy Let's indicate the number of atoms pointing up and down with The total energy of the system is Note that we are neglecting the interaction between the dipoles N and N = N N U B ( N N ) B ( N 2 N ) The magnetization of the system is: M ( N N ) =− U B We would like to know how these quantities depend on temperature: U ( T )= ?
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• 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.

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

• 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.

Dana University of Pennsylvania ‘17, Course Hero Intern

• 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.

Jill Tulane University ‘16, Course Hero Intern