【字幕付】物質中の電磁気学(Maxwell)の方程式

We'll discuss how Maxwell's equations in a material are expressed, assuming that Maxwell's equations in a vacuum are already known. Of course, Maxwell's equations in a material are also covered in first-year college electromagnetism textbooks, so we'll skip over the mathematical rigor and focus on the essence of the equations. We'll explain the form of Maxwell's equations in a material, as well as when the permittivity and permeability of a material are applicable. Finally, we'll explain why, as far as the electric and magnetic fields of light are concerned, the permeability of a material can be approximated as being roughly equal to that in a vacuum. 0:00 Introduction (overview of this video) 1:01 Is there no charge in a "charge-neutral" material? 3:27 Polarization effects occurring in an electric field even in charge-neutral materials 4:57 Electric dipole moment and polarization vector 9:18 The effect of polarization vectors on the electric field in materials and polarization charge 12:58 Gauss's law in materials considering polarization charge 16:02 Gauss's law in materials expressed in terms of the electric flux vector D and the dielectric constant of the material 20:10 The effect of a magnetic material placed in a magnetic field 21:33 Magnetizing current, Ampere's law in materials, and "magnetic field strength" H 23:54 "Polarization current" and Ampere-Maxwell's law in materials 26:24 Maxwell's equations in materials (summary) 27:53 When the electromagnetic field changes dramatically over time, why can we approximate the permeability of a material as being roughly equal to that in a vacuum? Other videos and playlists mentioned in this video: Schrödinger equation for electrons in hydrogen atoms    • 水素原子中電子のSchrödinger方程式   Verifying the nuclear structure of atoms through Rutherford scattering    • ラザフォード散乱による原子の有核構造の検証   [Subtitled] The essential importance of symmetry in quantum mechanics: Another distinction between classical and quantum mechanics    • 【字幕付】量子力学における対称性の本質的重要性: もう一つの古典と量子を分つもの   Image of the electromagnetic field seen in Gauss's theorem (divergence theorem), and the law of conservation of charge as an application of the theorem    • ガウスの定理(発散定理)にみる電磁場のイメージ、および定理の応用としての電荷保存則   [Subtitled] Electromagnetic description of light (2026 version)    • 【字幕付】光の電磁気学的記述(2026年版)   This explanation is by Professor Akira Sekiyama of the Department of Electronic and Physical Sciences, Faculty of Engineering Science, Osaka University. Sekiyama Laboratory Website: http://decima.mp.es.osaka-u.ac.jp BGM: Hopes Beside You (Music by Shimtone) #Electromagnetism #Maxwell #Matter #Laws #DielectricConstant #Polarization #Magnetization #ElectricField #ElectricFluxDensity #MagneticField #Physics #CondensedMatterPhysics #SchoolofEngineeringScience #OsakaUniversity