共查询到20条相似文献,搜索用时 0 毫秒
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通过2个光电门记录铁球通过的时间,利用Excel对实验数据进行分析处理,探究下落高度和时间的关系,从而得出自由落体运动是匀变速直线运动的结论. 相似文献
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用地面和地心两种参考系计算落体南偏的结果一致吗--落体偏南问题的再研究之一 总被引:1,自引:0,他引:1
不少章采用不同的方法和不同的参考系对落体偏南问题进行了讨论,并且得到了相同的结果:x=(2/3)h^2w^2cos λ/g,h,λ和w分别为落体的初始高度、纬度和地球角速度.在地面参考系中,它们仅考虑了科里奥利力对落体偏南运动的影响,也有个别章还考虑了惯性离心力对落体运动的影响,使落体的南偏结果有了较大的修正:x=(3/2)h^2w^2cosλsinλ/g,本发现了其中一些章之间存在相互矛盾的地方,并用地心参考系中落体运动的椭圆轨道严格计算了落体南偏的大小,结果为多数有关章相应结果的6倍。 相似文献
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应用分析力学理论和方法,研究了两种情况下的阻尼落体运动:1)阻力大小与速度成正比;2)阻力大小与速度平方成正比.对两种运动分别给出了等效的Lagrange函数和Hamilton函数,并应用第一积分法、点变换法、正则变换法和Ham-ilton-Jacobi方程法等不同的求解方法进行了求解. 相似文献
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旋转孔径白光散斑照相法的研究 总被引:3,自引:1,他引:2
本文报道利用旋转孔径法进行白光散斑照相,研测动态问题.其不仅具有旋转孔径激光散斑照相的优点,而且最突出的优点是能走出实验室,到现场进行动态测量研究. 相似文献
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The effect of toroidal field on the rotating magnetic field current drive in rotamak plasmas 下载免费PDF全文
A rotamak is one kind of compact spherically shaped magnetic-confinement device. In a rotamak the plasma current is driven by means of rotating magnetic field (RMF). The driven current can reverse the original equilibrium field and generate a field-reversed-configuration. In a conventional rotamak, a toroidal field (TF) is not necessary for the RMF to drive plasma current, but it was found that the present of an additional TF can influence the RMF current drive. In this paper the effect of TF on the RMF current drive in a rotamak are investigated in some detail. The experimental results show that addition of TF increases the RMF driven current greatly and enhances the RMF penetration dramatically. Without TF, the RMF can only penetrate into plasma in the edge region. When a TF is added, the RMF can reach almost the whole plasma region. This is an optimal strength of toroidal magnetic field for getting maximum plasma current when Bv and radio frequency generator power are fixed. Besides driving current, the RMF generates high harmonic fields in rotamak plasma. The effect of TF on the harmonic field spectra are also reported.[第一段] 相似文献
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ABSTRACTThe paper examines the influence of γ radiation on the stability of the insulation characteristics of the stator winding of rotating electrical machines. The tested insulation characteristics are loss tangent angle, resistance, polarization factor, threshold voltage of partial discharge, breakdown voltage, coefficient of proportionality and lifetime exponent. The radiation dose was used as the γ radiation parameter. Different winding areas have been specifically tested in which a different impact is expected on technological winding production process. Tests were performed on a representative statistical sample under well-controlled laboratory conditions. The combined measurement uncertainty of the experimental procedure was about 5%. 相似文献
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在相互作用表象中,研究了Lamb-Dicke区内单个超冷囚禁离子与一束驻 波型激光相互作用的动力学行为。由于没有引入旋转波近似,离子的运动随着Lamb-Dicke 参数η和Rabi频率Ω的增大趋向于混沌。所得结果与旋转波近似下的结果作了比较 。 相似文献
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The effect of fractional thermoelasticity on a two-dimensional problem of a mode I crack in a rotating fiber-reinforced thermoelastic medium 下载免费PDF全文
This article is concerned with the effect of rotation on the general model of the equations of the generalized thermoe- lasticity for a homogeneous isotropic elastic half-space solid, whose surface is subjected to a Mode-I crack problem. The fractional order theory of thermoelasticity is used to obtain the analytical solutions for displacement components, force stresses, and temperature. The boundary of the crack is subjected to a prescribed stress distribution and temperature. The normal mode analysis technique is used to solve the resulting non-dimensional coupled governing equations of the problem. The variations of the considered variables with the horizontal distance are illustrated graphically. Some particular cases are also discussed in the context of the problem. Effects of the fractional parameter, reinforcement, and rotation on the varia- tions of different field quantities inside the elastic medium are analyzed graphically. Comparisons are made between the results in the presence and those in the absence of fiber-reinforcing, rotating and fractional parameters. 相似文献
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Discussion on the event horizon and quantum ergosphere of dynamic rotating black holes in a tunneling framework 下载免费PDF全文
According to the Parikh--Wilczek tunneling framework, the locations of the local horizons of dynamic rotating black holes can be worked out. The calculations show that the quantum ergosphere of the black hole is identical with the tunneling potential barrier set by particle's tunneling across the relevant horizon. Then, some discussions on the origin of the Hawking radiation will be shown. 相似文献
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Massimo Cerdonio Giovanni A. Prodi Stefano Vitale 《General Relativity and Gravitation》1988,20(1):83-87
We are proposing a ground-based experiment to detect the Lense-Thirring drag due to the rotating earth by an off-line comparison between an astrometric measurement of the Earth rotation and an inertial measurement of the angular velocity of the laboratory. It is shown that the former, by means of routine observations of Very Long Baseline Interferometry, has already reached the accuracy needed to perform a 3 % experiment on a time span of 1 yr. We propose to perform the latter by a dynamical detector of local rotation of novel conception, the Gyromagnetic Electron Gyroscope. Its principle of operation is briefly discussed together with its response to rotationlike gravitational fields. 相似文献
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Discussion on event horizon and quantum ergosphere of dynamic rotating black holes in a tunneling framework 下载免费PDF全文
According to the Parikh-Wilczek tunneling framework, the locations of the local horizons of dynamic rotating black holes can be worked out. The calculations show that the quantum ergosphere of the black hole is identical with the tunneling potential barrier set by particle’s tunneling across the relevant horizon. Then, some discussions on the origin of the Hawking radiation will be shown. 相似文献
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指出了某些文献中的问题,根据电荷守恒定律,证明了由转动磁场所导致的电场E=±v×B的散度,并非与真实的电荷体密度有本质上的关联,而只是一种相对论效应.并根据电磁场变换原理,给出了轴对称导体在均匀稳恒磁场中转动时表面电荷密度及其电磁场的求解方法,得出了在均匀稳恒磁场中转动的导体球表面电荷密度及其电磁场. 相似文献
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The extended Boltzmann equation introduced in previous papers is used to compute the torque exerted on a macroscopic sphere or cylinder placed in a dilute gas, when the mean free path of the gas molecules is small compared to the characteristic dimension of the sphere or cylinder. The usual hydrodynamic results are recovered in this kinetic theory calculation.Work supported in part by the National Science Foundation Grant No. CHE 77-16308. 相似文献
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The Impact of the New Earth Gravity Models on the Measurement of the Lense–Thirring Effect 总被引:1,自引:0,他引:1
We examine how the new forthcoming Earth gravity models from the CHAMP and, especially, GRACE missions could improve the measurement of the general relativistic Lense–Thirring effect according to the various kinds of observables which could be adopted. In a very preliminary way, we use the first recently released EIGEN2 CHAMP–only and GGM01C GRACE–based Earth gravity models in order to assess the impact of the mismodelling in the even zonal harmonic coefficients of geopotential which represents one of the major sources of systematic errors in this kind of measurement. However, discretion is advised on evaluating the reliability of these results because the Earth gravity models used here, especially EIGEN2, are still very preliminary and more extensive calibration tests must be performed. According to the GGM01C model, the systematic error due to the unmodelled even zonal harmonics of geopotential amounts to 2% for the combination of the nodes of LAGEOS and LAGEOS II and the Perigee of LAGEOS II used up to now by Ciufolini and coworkers in the currently performed LAGEOS-LAGEOS II Lense-Thirring experiment, and to 14% for a combination explicitly presented here which involves the nodes only of LAGEOS and LAGEOS II. 相似文献