1, the first law of thermodynamics: δ e = q+a.

2. The second law of thermodynamics: isolated system: δ s >; 0。

3. Equation of state of ideal gas: P=nkT(n=N/V, k=R/N0).

4. Magnetic induction intensity: B=Fmax/qv(T).

5. Thin film interference: 2ne+λ/2=kλ (bright stripe).

6. mechanical energy: E=EK+EP.

7. Relationship between angular velocity and speed: V=rω.

8. Kinetic energy: mV2/2.

9. photoelectric effect equation: hν= mv2+A, etc.

The field of physics research can be divided into the following four aspects:

1.？ Physics of condensed matter-the study of macroscopic properties of matter. These phases contain a lot of components, and the interaction between components is very strong. The most familiar condensed phases are solids and liquids, which are formed by bonds between atoms and electromagnetic forces.

2.？ Atoms, molecules and optical physics-the study of the interaction between matter and matter, light and matter within the scope of atomic size or several atomic structures. These three areas are closely related. Because they use similar methods and related energy levels.

3. High energy/particle physics-particle physics studies the basic components of matter and energy and their interactions; Also known as high energy physics.

4.？ Astrophysics-Astrophysics and modern astronomy apply physical theories and methods to study the structure and evolution of stars, the origin of the solar system and related problems of the universe. Because of the wide range of astrophysics, it uses many physical principles, including mechanics, electromagnetism, statistical mechanics, thermodynamics and quantum mechanics.