Search
astrophysics (85)biophysics (18)chemistry (23)electric field (71)electric current (75)gravitational field (81)hydromechanics (146)nuclear physics (44)oscillations (57)quantum physics (31)magnetic field (43)mathematics (89)mechanics of a point mass (298)gas mechanics (87)mechanics of rigid bodies (221)molecular physics (71)geometrical optics (78)wave optics (65)other (167)relativistic physics (37)statistical physics (21)thermodynamics (154)wave mechanics (51)
thermodynamics
2. Series 19. Year - 4. heat conductivity of metals
Derive the temperature dependence of heat conductivity of metals, if the temperature dependence of electrical conductivity is known.
For free electrons in metal the model of ideal gas can be used, e.g. free electrons are moving without external forces on straight lines (ions are not considered) and sometimes collides with other electrons, when they change the direction and amplitude of velocity.
The heat transferred by crystal lattice is negligible to the heat transferred through free electrons. Each electron has heat capacity $c$, which is temperature independent.
Honza při čtení Ashcrofta.
4. Series 18. Year - E. evening tea
The FYKOS organisers had a long discussion over a cup of tea. The point was the cooling of the tea. Whether the tea cup is cooled by evaporation, conduction of heat or radiation of heat. Try to solve the same problem using some experiment.
Navrhl Jirka Franta.