滑动变阻器“口”形电路规律的巧用

如图1所示电路，滑动触头P把变阻器R分为aP和bP两部分电阻并联，形如“口”字，故称为“口”形电路，可知：当触头P在变阻器端点时，并联电路的总电阻最小(为零)；当触头P在变阻器的中点时，并联电路的总电阻最大(为R／4)，或者说，当一个定值电阻被等分时，     

电路实验设计中滑动变阻器的分压式接法

在电路实验设计中，常通过滑动变阻器来调节电路中的电流和电压．滑动变阻器接入电路有两种方式：限流连接(如图1)、分压连接(如图2)．     

滑动变阻器调节的有效性分析

滑动变阻器在电路中的调节作用, 在限流和分压两种接法中得以体现, 所谓调节方便有效, 就是指电 路中的电流或电压等参量随滑动变阻器的滑片线性变化, 但其阻值的大小会在其中起到至关重要的影响     

自制变色滑动变阻器

自制了变色滑动变阻器,即在滑动变阻器上涂上变温油墨,当滑动变阻器有电流流过时,利用电流的热效应,油墨颜色将发生改变,由此形象直观地显示变阻器上电流流过的情况。     

用图像分析限流和分压接法中滑动变阻器的选取

借助Ux-Rap图像分析得出滑动变阻器的选取原则:控制电路采用限流接法时,要求滑动变阻器的最大阻值与被测电阻的阻值接近,即接近为原则;控制电路采用分压式接法时,滑动变阻器的最大阻值应远小于被测电阻的阻值,故在分压接法中,应选择阻值较小而额定电流较大的滑动变阻器.     

浅析电学实验中如何选择滑动变阻器

讨论了在电学实验中如何选择滑动变阻器的有关问题.     

直流电路中动态变化问题的分析方法

在直流电路中，由于滑动变阻器滑片的移动，或者由于电键的接通与断开，或者由于某一用电器的突然烧坏等因素，导致电路中的总电阻发生变化，从而使电路中的电流、电压和电功率等物理量随之变化，这类问题叫做电路动态变化问题，它是直流电路中最常见的一种题型。     

也谈滑动变阻器在电路中的两种连接方式

滑动变阻器是电路中的重要元件,在电路中起着保护和调节作用.有关滑动变阻器连接的文章很多,但由于普遍缺乏定量的分析,所以很难让学生理解.本文通过定量研究U0-x图象的方法,分析两种连接的适用范围,供大家参考.     

滑动变阻器的非常规用法探析

在滑动变阻器使用方法上打破常规,加以创新,使其功能由制流与分压拓展为分压、降压、转变极性,变直流为交流、替代开关和充当多用电源．     

用Excel讨论在电阻测量中滑动变阻器的选取

在电学实验中,为了改变电路中的电流或电压,通常用滑动变阻器来控制电路.滑动变阻器在电路中可以采用限流接法,也可以采用分压接法.在选择滑动变阻器时,涉及到两个问题:一是对给定的滑动变阻器,应该选限流接法还是分压接法?     

滑线式惠斯登电桥触点位置对测量结果的影响

选择三个不同量级的电阻,分析触点不同位置和两种求平均值的数据处理方法对测量结果的影响。测量结果表明,触点位置直接影响电阻测量的准确度。当触点位于电阻丝的中间区域时,触点位置对测量结果的影响较小,而在电阻丝两端区域影响较大。在数据处理方法方面几何平均算法要优于算术平均算法。     

滑线变阻器制约电路的因素分析

滑线变阻器接入电路，主要有限流式、“口”式、“桥”式、分压式等方式，会对整个电路起控制作用，使电路中的电压、电流等只能在某一范围内发生变化．变化的范围由滑线变阻器接入电路的方式以及滑线变阻器最大阻值和允许通过的最大电流等因素共同制约．     

True Grain-Boundary Slipping in Coarse- and Ultrafine-Grained Titanium

The temperature dependence of internal grain-boundary friction in coarse- and ultrafine-grained titanium is investigated. It is demonstrated that true grain-boundary slipping causes internal grain-boundary friction in ultrafine-grained titanium, as in coarse-grained metals. It is established that when going from the coarse-grained structure with perfect grain boundaries to ultrafine-grained structure with imperfect grain boundaries, the temperatures of the beginning and intense development of true grain-boundary slipping decrease together with the activation energy of this process. The diffusion mechanism of true grain-boundary slipping is justified for both structural states.     

Slipping superdislocation a/2〈112〉 in the L10 superstructure

A new type of slipping superdislocation with a Burgers vector a/2 (112) is proposed for alloys with the Ll₀ superstructure. A superdislocation of this kind has a configuration similar to that of the well-knowna 110 superdislocation, but differs from the latter (in the case of imperfect long-range order) by having a high value of the retarding force due to the disruption of correlation.Translated from Izvestiya Uchebnykh Zavedenii, Fizika, Vol. 16, No. 7, pp. 123–126, July, 1973.     

Deformation of the Sliding Surface of Structural Steel Under the Conditions of Sliding Current Collection

Russian Physics Journal - Dry sliding of a model specimen of general-purpose steel against the hardened steel is studied under the action of electric current of a density higher than 250 A/cm2...     

Sliding pressure analysis using the second law

Over the last 20 years many technical papers have been written by manufacturers on the concept of reducing or sliding the turbine inlet pressure at lower loads to reduce frictional losses. This paper takes a unique look at why sliding pressure is needed using both the first and second laws of thermodynamics. The derived equations are applied to the flow of steam across a single valve and then applied to a simplified turbine control valve system. The optimal control point at which to initiate sliding pressure is analyzed. It is also shown that the optimal operating point is not when the second-law efficiency is maximum, but when the first-law efficiency is maximized.