用波耳共振仪研究受迫振动

本文介绍了用波耳共振仪器测量受迫振动的振幅－频率特性与相位－频率特性。     

自制受迫振动与共振演示探究仪

教材手摇式受迫振动与手动共振实验装置稳定性差,演示的实验现象不直观且不连续,均未达到定量探究.针对装置和实验现象的不足,制作了受迫振动与共振演示探究仪,该装置能直观演示阻尼振动、受迫振动和共振现象;借助Tracker、Origin和Pr视频软件的辅助能更高效率地实现可视化教学.     

相位差法测受迫振动的阻尼系数

利用音叉在受迫阻尼振动中速度与驱动力之间的相位差测定了阻尼系数.该方法在系统的稳定状态下读数,克服了通常所用的振幅衰减方法中的不稳定性,可降低人为因素给测量带来的误差.     

用波耳共振仪研究受迫振动

本文介绍了用波耳共振仪器测量受迫振动的振幅－频率特性与相位－频率特性     

用波尔共振仪研究受迫振动特性

介绍了波尔共振仪实验系统的基本结构及原理,测定了幅频和相频特性曲线,分析了实验系统误差.研究发现,当系统发生共振时,驱动频率和固有频率近似相等且相位差为90°.     

用钕铁硼制作阻尼振动、受迫振动及共振演示仪

利用稀土永磁性材料钕铁硼(Nd-Fe-B)设计制作出了新型阻尼振动、受迫振动及共振演示仪.该演示仪器可演示阻尼振动的3种状态(欠阻尼状态、临界阻尼状态、过阻尼状态)、受迫振动及共振现象.     

线性受迫阻尼振动发生共振的条件及特征

从线性受迫阻尼振动发生共振的条件及其特点出发,对其进行了详细的分析与讨论,得出：对于线性受迫阻尼振动系统,位移共振,速度共振,加速度共振中,只有速度共振是类简谐振动。     

利用波耳共振仪研究受迫振动的非线性特性

利用波耳共振仪实测数据,通过对其轴承摩擦进行理论修正,建立受迫振动的非线性方程,并采用Matlab软件求解其数值解的方法,研究了受迫振动的非线性特性.     

波尔共振仪实验的不确定度分析

共振现象普遍存在于物理学领域,高校开设波尔共振仪实验以加深学生对共振概念的认识,文中讨论了摆轮作自由振荡、阻尼振荡和受迫振动的测量结果的不确定度,并分析了可能影响测量结果的因素,该结果对理解共振现象和分析测量不确度具有一定的指导和借鉴意义。     

介质光栅导模共振耦合波分析

导模共振是由于光栅介质内高级次子波耦合进光栅所支持的泄漏模中,导致传播波能量重新分布的结果.采用严格的耦合波方法,通过分析波导的导波模式,正确估计出弱调制介质光栅导模共振的位置.并对导模共振与光栅厚度、基底厚度以及入射角的关系作了讨论.通过采用抗反射设计,获得了具有对称、低旁带特点的窄带共振峰 关键词： 导模共振 耦合波     

阻尼耦合振动的Lagrange函数和Hamilton函数

本文研究两种阻尼耦合振动的分析力学化.首先,利用坐标变换将方程变换成自伴随形式;其次,根据Engels方法计算得到Lagrange函数;最后,由逆变换导出原始方程的Lagrange函数,以及Hamilton函数.     

利用光电鼠标实现玻尔共振仪混沌现象的数据采集

用半导体激光器作为光源,利用鼠标接收经由金属物体漫反射的激光,实现了对玻尔共振仪产生混沌现象的数据进行非接触的测量过程.     

A2B模型阻尼受迫振动方程组的通解

导出了A2B模型阻尼受迫振动方程组的通解,并讨论其算例和图像.     

A concise quantum mechanical treatment of the forced damped harmonic oscillator

By selecting a right generalized coordinate X, which contains the general solutions of the classical motion equation of a forced damped harmonic oscillator, we obtain a simple Hamiltonian which does not contain time for the oscillator such that Schrödinger equation and its solutions can be directly written out in X representation. The wave functin in x representation are also given with the help of the eigenfunctions of the operator \(\hat X\) in x representation. The evolution of \(\left\langle {\hat x} \right\rangle \) is the same as in the classical mechanics, and the uncertainty in position is independent of an external influence; one part of energy mean is quantized and attenuated, and the other is equal to the classical energy.     

Soliton dynamics in damped and forced Boussinesq equations

We investigate the dynamics of a lattice soliton on a monatomic chain in the presence of damping and external forces. We consider Stokes and hydrodynamical damping. In the quasi-continuum limit the discrete system leads to a damped and forced Boussinesq equation. By using a multiple-scale perturbation expansion up to second order in the framework of the quasi-continuum approach we derive a general expression for the first-order velocity correction which improves previous results. We compare the soliton position and shape predicted by the theory with simulations carried out on the level of the monatomic chain system as well as on the level of the quasi-continuum limit system. For this purpose we restrict ourselves to specific examples, namely potentials with cubic and quartic anharmonicities as well as the truncated Morse potential, without taking into account external forces. For both types of damping we find a good agreement with the numerical simulations both for the soliton position and for the tail which appears at the rear of the soliton. Moreover we clarify why the quasi-continuum approximation is better in the hydrodynamical damping case than in the Stokes damping case. Received 22 August 2001 and Received in final form 7 December 2001     

音叉受迫振动规律及计算机实时测量

对音叉作受迫振动的规律及音叉振动周期与双臂质量的关系进行了研究,自制了新型的音叉受迫振动与共振实验仪,该仪器不仅可以手工调节做实验,而且可以实现计算机实时测量.     

非简谐阻尼振动与匀加速直线运动合成实验

分析了小球在斜槽内横向作非简谐阻尼振动同时又在其纵向作匀加速直线运动的轨迹的理论公式.让粘满碳粉的小球在铺有坐标纸的斜槽内运动,记录真实运动轨迹,从实验图像中可以看出振幅越来越小、波长越来越长,这与理论分析相符.     

Analysis of the electrically forced vibrations of piezoelectric mesa resonators

We study the electrically forced thickness-shear and thickness-twist vibrations of stepped thickness piezoelectric plate mesa resonators made of polarized ceramics or 6-ram class crystals. A theoretical analysis based on the theory of piezoelectricity is performed, and an analytical solution is obtained using the trigonometric series. The electrical admittance, resonant frequencies, and mode shapes are calculated, and strong energy trapping of the modes is observed. Their dependence on the geometric parameters of the resonator is also examined.