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本文提供一个新的中学物理分组实验,以巩固学生对电容器串、并联的理论知识一、实验目的 1.研究串联电路中总电容与各分电容的关系; 2.研究并联电路中总电容与各分电容的关系。 相似文献
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"RLC串联电路暂态过程的研究"实验中电容系统误差的测量与修正 总被引:1,自引:0,他引:1
在"RLC串联电路暂态过程的研究"实验中,由于示波器两测量探头间电容和电容箱"零电容"的存在,导致阻尼振荡周期的理论计算值与实验值之间可能产生非常大的误差.本文通过测量上述两类电容,对周期的理论计算值进行了修正,使之与实验值的相对误差明显减小. 相似文献
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"电感和电容对交变电流的影响"演示实验的操作难度大且现象不明显,为此介绍了2种演示该实验的方法,一是通过将电灯分别与电感(电容)和电阻串联对比进行实验来演示电感和电容对交变电流的影响;二是通过信号发生器和示波器来研究交流电对电感(电容)的影响.2种方法演示效果均较好. 相似文献
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平行板电容器的电容是高中物理电学部分的重要演示实验.教材中的探究方案只能定性研究,且理解难度大,实验效果不明显.为解决以上问题设计了简单稳定且能定量探究平行板电容器电容决定因素的实验装置.实验装置采用单面覆铜板作为电容器极板,利用A4纸或塑料文件夹做电介质,通过实验探究得出平行板电容器电容与极板正对面积成正比,与极板间... 相似文献
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平板电容作用力的扭摆测量方法罗俊,范淑华(华中理工大学武汉430074)平板电容两极板之间存在相互作用力是电磁学中为人们所熟悉的一个结论,从实验上直接观测电容作用力效应通常的办法是采用静电天平或电磁天平.本文提出平板电容作用力的扭摆测量方法.其实验设... 相似文献
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1教学中实验存在的问题"电容器的电容"这节课的教学重点是定义电容器的电容和探究影响平行板电容器电容的因素.用比值定义法定义电容,教材是这样表述的,"实验表明,一个电容器所带的电荷量Q与电容器两极间的电压U成正比,比值Q U是一个常量."但教材并未给出此实验的具体方案.如果没有实验探究,仅凭讲解,学生很难理解Q U是一个常量的事实.因此,非常需要设计一个研究电容器两极间电压U与电荷 相似文献
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Weihai Fang Shanjia Xu 《International Journal of Infrared and Millimeter Waves》2006,27(12):1683-1694
The effects of left-handed materials (LHM) on frequency selective reflection and transmission characteristics of dielectric
periodic structures are carefully investigated using a method which combines the multimode network theory with the rigorous
mode matching method. In addition, the effects of LHM dielectric loss on the selective properties are also given. It has been
shown that the selective behavior of periodic structures can be modified by adding LHM layers above and below the periodic
layer.
Supported by the National Natural Science Foundation of China (No. 60171037) (No. 60371010) and (No. 63531020) 相似文献
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介绍了清华大学物理系研制的一个测量高温超导薄膜微波表面电阻的系统,展示了测量的原理和过程.本系统是按照目前国际上高温超导薄膜的微波表面电阻的测量标准方案(ICE/TC90)选定的 TE011- TE013双介质谐振器法来对超导薄膜进行测量.介质谐振器谐振的中心频率约为11.96 GHz,具有很高的准确性和灵敏度.在液氮(77 K)温度下,用物理所提供的两片YBCO薄膜测量,TE011和TE013模式的无载Q值分别达到5.57×10 5和1.51×10 6, 就我们所知,这是国内所报道的最高Q值.其Rs(77 K,10 GHz)平均值为263微欧.因此,本系统可以较为准确地测量表面电阻很小(300微欧以下)的高温超导薄膜. 相似文献
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点电荷在三层介质中势的物理解释与光学类比 总被引:2,自引:1,他引:1
导出点电荷三层介质中的电势,并给出了物理解释,利用光学类比处理镜像问题,直观地给出多怪平面介质中镜像电荷的位置和大小。 相似文献
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Weihai Fang Shanjia Xu 《International Journal of Infrared and Millimeter Waves》2006,27(12):1667-1681
The frequency selective characteristics of a new dielectric periodic structure composed of left-handed materials (LHM) are
carefully studied by a method which combines the multimode network theory with the rigorous mode matching method. The variations
of the frequency selective characteristics with structure parameters and dielectric loss are presented and comparisons for
the frequency selective properties between RHM and LHM gratings are also shown with some explanations. Guidelines for accurate
design of the LHM dielectric frequency selective surface are given.
Supported by the National Natural Science Foundation of China (No. 60171037) (No. 60371010) and (No. 63531020) 相似文献
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EFFECT OF DIELECTRIC CONSTANT ON THE EXCITON GROUND STATE ENERGY OF CdSe QUANTUM DOTS 总被引:1,自引:0,他引:1 下载免费PDF全文
The B-spline technique is used in the calculation of the exciton ground state energy based on the effective mass approximation (EMA) model. The exciton is confined in CdSe microspherical crystallites with a finite-height potential wall (dots). In this approach, (a) the wave function is allowed to penetrate to the outside of the dots; (b) the dielectric constants of the quantum dot and the surrounding material are considered to be different; and (c) the dielectric constant of the dots are size-dependent. The exciton energies as functions of radii of the dots in the range 0.5-3.5 nm are calculated and compared with experimental and previous theoretical data. The results show that: (1) The exciton energy is convergent as the radius of the dot becomes very small. (2) A good agreement with the experimental data better than other theoretical results is achieved. (3) The penetration (or leaking) of the wave function and the difference of the dielectric constants in different regions are necessary for correcting the Coulomb interaction energy and reproducing experimental data. (4) The EMA model with B-spline technique can describe the status of excition confined in quantum dot very well. 相似文献
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纳米颗粒在制冷剂中的分散特性研究 总被引:5,自引:2,他引:5
本文利用沉降观察法和分光光度计吸收测量法,实验研究了纳米颗粒在制冷剂中的分散特性.结果表明:纳米颗粒属性和制冷剂属性对分散稳定性影响较大,制冷剂的极性和介电常数是主要的影响因素. 相似文献
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The propagation of electromagnetic waves along open periodic, dielectric waveguides is formulated in the case that surface
wave is guided and propagates normally to the corrugation. Our approximate analysis with the propagation characteristics is
to consider a corresponding bounded waveguide problem in which perfect electric or magnetic walls are introduced, and the
periodic corrugation is regarded as consisting of step discontinuities connected by a length of uniform slab waveguide. By
properly taking into account of both surface modes and only a few non-surface-modes, a novel network approach is proposed
for characterizing step discontinuity based on the generalized conservation of complex power technique (GCCPT). Employing
solution selection rule (SSR), we can readily derive propagation characteristics in the Bragg interaction region. A number
of numerical results are shown to demonstrate the usefulness of our approach. 相似文献
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