共查询到20条相似文献,搜索用时 93 毫秒
1.
2.
3.
4.
5.
静电场和稳恒电流磁场的两种物理图象:对电动力学教材的一点补充 总被引:1,自引:1,他引:0
本文介绍静电场和稳恒电流磁场的两种等价的物理图象.对这些图象有清晰的认识可以使学生在解决具体问题时思路清楚,避免一些错误. 相似文献
6.
Jiang Linhan 《物理与工程》1998,(3)
从点电荷的场强公式出发,根据狭义相对论中场强张量的变换,推导出了静电场和稳恒电流磁场的诸定律,使学生对电场和磁场的统一性有了更为深刻的认识. 相似文献
7.
8.
从点电荷的场强公式出发,根据狭义相对论中场强张量的交换,推导出了静电场和稳恒电流磁场的诸定律,使学生对电场和磁场的统一性有了更为深刻的认识。 相似文献
9.
用立体角概念和计算式导出高斯定律、安培环路定律,并举实例说明对具有一定对称性的静电场与稳恒磁场的场强分布可以较简捷地求解。 相似文献
10.
11.
对于通以恒定电流的有限长厚壁螺线管,用柱函数展开法推导出矢势的表达式,再根据磁感应强度与矢势的关系式得出磁场的积分形式表达式.用直接积分的方法,计算出厚壁螺线管内部和外部的磁场分布的级数表达式.另外还用本文得出的公式求得中轴线上的磁场. 相似文献
12.
对于通以恒定电流的有限长螺线管,首先用柱函数展开法推导出矢势的表达式,再利用磁感应强度与矢势的关系式,得出积分形式的磁场表达式.然后用直接积分的方法计算出磁场分布的级数表达式.最后讨论了某些特殊位置处的磁场. 相似文献
13.
采用基于OpenFOAM环境自主开发的低磁雷诺数磁流体求解器,对45°和90°突扩矩形管中液态金属流体在受到垂直流向的外加磁场作用时的速度、感应电流、压力的分布及突扩位置处的MHD三维现象进行数值模拟.结果表明:磁场沿突扩方向时,由于无回流涡,45°比90°突扩管在肩部位置速度分布更优.哈特曼数增大,强射流和突扩结构,在突扩肩部位置引发流动的不稳定性.伴随感应电流的不稳定,流动不稳定发展到突扩位置上游.磁场沿垂直突扩方向时感应电流的三维效应显著.哈特曼数增大,MHD压降显著增大.同方向磁场和相同哈特曼数,不同突扩角度的三维无量纲压力梯度无明显差异. 相似文献
14.
Can F. Delale 《Journal of statistical physics》1982,28(3):589-602
The Hilbert expansion to the Boltzmann equation is carried out for steady flow. It is shown that the first term in the Hubert series for the distribution function is a local Maxwellian leading to the steady Euler equations. The steady field equations that follow from the solution of the second term in the series are derived. The formulas for thermal conductivity and for viscosity of Hilbert that appear in the steady field equations of the second approximation are shown to be precisely the same as those obtained by Chapman and Enskog. The procedure to obtain higher approximations by Hubert's method is summarized. 相似文献
15.
强磁场中的Cs原子有较大的超精细塞曼分裂,实验用频率可调谐的窄线宽半导体激光调谐到各超精细塞曼能级上进行光泵浦,利用稳态吸收谱方法研究了原子的光泵浦。表明基态超精细相互作用的碰撞修正项导致的驰豫跃迁是谱形状和电子自旋极化新特征的根缘。同时提出了强场下极化度的一种测量方法。 相似文献
16.
17.
The pair distribution function of a monodisperse magnetic fluid simulated by a liquid made of dipolar hard spheres with constant
magnetic moments is calculated. The anisotropy of the pair distribution function and the related structure factor of scattering
in a dc uniform magnetic field are studied. The calculation is performed by diagrammatic expansion in the volume concentration
of particles and the interparticle magnetic-dipole interaction intensity using a thermodynamic perturbation theory. Limitation
by three-particle diagrams makes it possible to apply the results obtained to magnetic fluids with a moderate concentration.
Even for low-concentration and weakly nonideal magnetic fluids, the anisotropic interparticle magnetic-dipole correlations
in a magnetic field lead to the repulsion of particles in the direction normal to the field and to the formation of particle
dimers along the field. 相似文献
18.
The equilibrium statistical mechanics of a nearly classical one-component plasma, submitted to a strong magnetic field, is studied, in three or two dimensions, by a suitable expansion of the Wigner distribution function. A strong magnetic field quenches the quantum fluctuations transverse to the field. The situation is especially simple for a two-dimensional plasma, which has a classical behaviour in the strong-field limit; as a consequence, a classical Wigner crystallization can be induced by the magnetic field. 相似文献
19.
Balance equation approach to the hot-electron transport in electric and magnetic fields is reformulated.The balance equations are re-derived from the Boltzmann equation. A new expression for the distribution function isreported in the present paper. It is homogeneous steady solution of the Boltzmann equation in constant relaxation timeapproximation. It holds when ωocτ < i or ωc < Te. As an example, the mobility of 2D electron gas in the GaAs-AlGaAsheterojunction is computed as a function of electric field and magnetic field. 相似文献
20.
Measurements of the angular flux distribution of the cathodic arc plasma (I ? 100 A) subjected to a transverse magnetic field (B ? 8.5 × 10-2 T) ae presented. The angular distribution without magnetic field approximately follows the cosine law. Expansion with transverse field is found to deviate strongly from the cosine law, the plasma being confined close to the cathode plane and expanding along the magnetic-field lines. Furthermore, time-resolved photographs of the expansion reveal the predicted pulsating behavior of the expanding plasma. 相似文献