感悟教师责任

一位科学家交给他的两位年轻助手各人一只灯泡，要求他们求出这灯泡的体积。其中的一位很快得出结果：先找来一只烧杯，注满水，然后把灯泡没入水中，灯泡排开了一定体积的水，他拿出灯泡，根据烧杯中空出的部分，很快计算出灯泡的体积。另一名助手，对灯泡又是用尺子量，又是用公式计算，忙了半天也没有忙出一个结果来。     

电流和电路综合测试题

一、基础知识回顾 1．节日的夜晚，一些高大的建筑物会用灯泡装点起来，点亮的灯泡映出建筑物的轮廓，显得美丽、壮观．如果发现有个别灯泡不亮，而其他灯泡都正常，说明这些灯泡是——联在电路中的．     

废灯泡的利用

废灯泡的利用重庆教育学院（６３００６７）陈道英灯泡的玻璃能经受高温，灯泡的形状与烧杯瓶相似，只要把废灯泡的金属帽去脱，可以代替烧瓶使用。现介绍一种取脱金属帽的简便方法及其利用。用抹布把灯泡玻璃部分包着（万一玻璃破碎，也不会伤人），左手拿着灯泡把它的金...     

小灯泡中所涉及的物理知识

1加工制造方面涉及的物理知识 1．1白炽灯泡为何做成梨形 因为灯泡的灯丝大多是利用熔点很高的钨制成的，灯泡工作时，灯丝的温度达到2000℃以上，一部分钨便会升华附着在灯泡的内壁上。时间一长，灯泡就会变黑降低亮度，影响照明效果。科学家根据气流是自下而上的特点，在灯泡内充有少量惰性气体，在惰性气体对流时，升华的黑色钨颗粒被气体卷到上方附着在灯泡的颈部，这样便可保持灯泡下部透明，使亮度不受影响。     

有电流通过 灯泡一定发光吗——析两道灯泡发光题

灯泡的亮度取决于它的实际功率．当实际功率等于额定功率时，灯泡正常发光；当实际功率略小于额定功率时，灯泡亮度比正常发光时暗；当实际功率远远小于额定功率时，尽管灯泡中有电流通过，但灯泡也不发光．许多家用电器上的指示灯就是这种情形。     

灯泡中的物理知识

灯泡是家庭电路中的一种必备电器，灯泡的构造和使用中蕴含着许多物理知识。掌握这些物理知识，对正确地使用灯泡和延长灯泡的使用寿命显得十分重要。     

电容器充放电演示实验的改进

如图1所示，当开关S拨向位置1时，电源给电容器C充电，线路中有充电电流流过小灯泡L，故小灯泡亮；当开关S拨向位置2时，电容器C通过小灯泡L放电，线路中有放电电流，故小灯泡L又亮一次．     

一道电学题的演变

题目有三只规格相同的灯泡（9V9W），接在9伏的电路中（如图1），则每个灯泡消耗的功率多大？解析如图1所示电路，三只灯泡串联接在电压为9伏的电路里，通过每个灯泡中的电流相同．因三个灯泡的规格相同，即三个灯泡的电阻相同（R灯＝U2额／P额），由串联电路的分压原理可知，加在三盏灯泡两端的电压相同，等于总电压的，根据即可求出灯泡消耗的功率；灯泡的电阻为：根据分压原理得，加在每盏灯两端的电压为：则每盏灯实际消耗的功率为：三盏灯发光均较暗．演变1．若用导线将A、C连接起来，则L1、L2被短接，只有L3连入电路，加在L3两端…     

普通白炽灯内气体压强的测量

白炽灯泡是日常生活中常见的一种东西，但一个小小的灯泡却包含着很多的科学知识，并且灯泡的发明故事中蕴含着丰富的科学精神和科学方法．那么，能否充分发掘灯泡内的资源，把灯泡开发成供中小学利用的探究素材？2005年本刊第1期刊登的文章《对一个实验现象的思考》就做了这样的尝试，文中介绍了灯泡内一种奇特的对流现象，其原因是灯泡内存在气体．但灯泡内气体的压强是多大？对灯泡内气体压强的测量能否也开发成探究资源？笔者在亲自实验和查阅资料的基础上作了一些初步的尝试，现将所做实验的整个过程整理如下，旨在为教师丰富探究资源做出一点努力．     

与灯泡有关的常见题型分析

灯泡是日常生活中的一种必备电器，家家都有，学生天天可以看得到、接触到，而且灯泡中的物理知识多，所以，近几年来不少中考题都涉及到有关灯泡的问题．[第一段]     

Electricity

In the early years of power generation the alternating voltage from a single coil (with 2 or more parallel paths) wascommutated to convert it to DC. Commutation essentially means reversing the negative polarity of the AC voltage so that the voltage produced does not alternately change, its sign and the current delivered by the generator flows in one direction. The purpose of producing direct current was that it could be used to run motors available in those days and light electric bulbs. AC motors which constitute more than 80% of today’s motors had not been invented at that time.     

Chlorocholine chloride and paclobutrazol treatments promote carbohydrate accumulation in bulbs of Lilium Oriental hybrids ‘Sorbonne’

The present study was to test the hypothesis that the plant growth retardants chlorocholine chloride (CCC) and paclobutrazol (PBZ) could improve the carbohydrate accumulation in lily bulbs by enhancing photosynthetic capacity and changing endogenous hormones. Plants of Lilium Oriental hybrids ‘Sorbonne’ were treated with a foliar spray of CCC or PBZ (both at 300 mg/L) solution, at six weeks after planting (6 WAP). The morphological parameters, endogenous hormone contents (gibberellic acid (GA), abscisic acid (ABA), and indole-3-acetic acid (IAA)), and carbohydrate contents were measured from 6 to 18 WAP, at 2-week intervals. The results showed that CCC increased the biomass of leaves and stems which might produce more photoassimilates available for transportation and utilization. However, PBZ treatment suppressed vegetative growth and favored photoassimilate transportation into bulbs. A slight delay of bud and anthesis formation was observed in both treated plants. CCC and PBZ treatments substantially enhanced the sucrose contents in leaves probably due to the increase of chlorophyll contents. Treatment with CCC or PBZ decreased GA but increased IAA contents in lily bulbs which might stimulate starch accumulation and formation of new scales. Our experiment suggested that CCC or PBZ treatment is an effective method to promote carbohydrate accumulation in lily bulbs.     

多媒体教室投影机保护装置的研制

利用单片机设计了一种用于保护多媒体教室投影机的装置,由于使用了后备电池,比市场上常用的保护器更可靠,它能在突然断电的情况下实现对投影机灯泡的冷却保护。     

番红花在青岛崂山地区露地栽培技术

分述番红花的生物学特性、栽培与管理、繁殖方法、病虫害防治、球茎收获与贮藏，为在青岛崂山地区推广番红花露地栽培技术，满足各地医药部门需求提供科学依据。     

Exploring the effects of concreteness fading across grades in elementary school science education

The present study investigates the effects that concreteness fading has on learning and transfer across three grade levels (4–6) in elementary school science education in comparison to learning with constantly concrete representations. 127 9- to 12-years-old elementary school students studied electric circuits in a computer-based simulation environment, where circuits remained concrete (bulbs) throughout the learning or faded from concrete to abstract (bulbs to resistors). The most important finding was that the outcomes seemed to be influenced by a developmental factor: the study found a significant interaction between condition and grade level in relation to learning outcomes, suggesting that the outcomes generally improved as a function of grade level, but that there were notable differences between the conditions regarding the improvement of outcomes across the three grades. According the results, learning with constantly concrete representations either took less time or resulted in better learning compared to concreteness fading. Because transfer is one of the central arguments for concreteness fading, a somewhat surprising finding was that the concrete condition succeeded at least as well as the fading condition on transfer tasks. The study also discusses why the results and issues related to the conceptualisation and operationalisation of central concepts in the study call for caution towards generalization and for more research with young learners across different grades.     

自制教具演示物体热导电特性

用废旧灯泡、木板等简单易得物品自制教具演示物体热导电特性,以帮助学生理解“绝缘体和导体的互相转化”,从而减轻教学难度,提高教学效率。     

车灯表面质量分级装置

This paper introduces an installation for quickly classifying automobile‘s metal reflectors based on their roughness.The measuring principle and the mechanical structure are presented.Schematics of circuits and experimental results are given.Elimination and reduction of the effect of background lights or different bulbs on the measuring results are also described in detail.     

以通电灯泡为道具的科学探究课的教学设计及实践

设计并组织了一场以通电灯泡为道具的科学探究课,学生在开展科学探究的过程中,既学到了热传递方面的科学知识,锻炼了实验操作能力,又训练了语言表达能力,培养了探索精神和理论联系实际的作风。     

Creativity in a cooperative group setting

This study was to determine whether cooperative small groups would stimulate creativity of fith and sixth grade students more than an individualized learning environment. Student aptitudes for creative and academic work were assessed on the Torrance Tests of Creative Thinking (Verbal Form A), analysis of student created electrical circuit diagrams, and a batteries and bulbs prediction test. A measure of student perceptions was also used to indicate any changes in attitudes toward the science activity and learning environment. A posttest control group design was used with 11 I fifth and sixth grade students. Half of the population worked by themselves, while the other half (experimental) worked in a student-structured environment on the same science activity which involved creating as many different types of electrical circuits from a given set of batteries and bulbs as possible. An overall conclusion is that fifth and sixth grade students working within small cooperative groups can be more creative as measured by a figural creativity test with electrical circuits than students working alone. The implication of this study is that small cooperative groups as well as individualized groups should be used in elementary science classes when creativity is one of the instructional objectives.     

多媒体设备维护二、三事

无盘工作系统能否正常工作与网络的性能是否良好密切相关,特别是在底层的结构上,一定要保证工艺,保证质量。在日常的维护工作中要十分注意这些细节。当投影机的投影效果下降,亮度降低,对比度下降时,不仅要检查灯泡使用时限,也要检查PBS镜片的状态,以确保维护完成后获得预期的效果。