The metal linear expansion coefficient of metal is studied common physical quantities ,to make amore accurate measurement of metal linear expansion coefficient,it lights amplification principle merged intothe field of measuring metal linear expansion coeficient,using self-made experimental devices such as lighisource ,light screen, heating device, etc. According to the geometric relationship between the reflection angleformed by the light path belore and after heating and the spot position before and after the light screen moves.the small shape variable of the metal is calculated through the moving distance of the spot ,and then the linearexpansion coefficient of the metal is obtained. The linear expansion coefficient of metal is obtained bycalculating the tiny shape varable of metal through the moving distance of the light spot.The average value ofthe linear expansion coefficient of copper is studied ,and compared with the standard value ,the relative error is0.05% ,and the method is extended to the measurement of the linear expansion coefficient of aluminum andtitanium,the relative error is less than 0.90% ,indicating that the method can be used for the measurement ofthe linear expansion coefficient of common metals.

The main factors affecting the accuracy of Wheatstone bridge are the sensitivity of Wheatstone bridge and the error of resistance box.In order to simplify the problem and obtain semi qualitative, semi quantitative and approximate theoretical results,an approximate model of resistance error is established. Combined with the existing theoretical formula of bridge sensitivity, the theoretical values of bridge arm resistance Rand R, when the measurement accuracy is the largest (extreme) are derived by calculating the error minimum.In addition,some practical problems are analyzed and discussed in detail.Although the results obtained are approximate. the research ideas. methods and concusions may not only provide theoretica guidance for Wheatstone bridge experiment,but also provide some clues and references for relevant theoretical research.

Ideological and political education is an educational idea and practice with moral education as the basic task，which is the new requirement of higher education put forward by the party and the country in the new era．It first discusses the connotation of ideological and political education，and then takes the experiment of“using fast electronic verification of relativistic effect”as an example，puts forward the concrete strategies and practical application of curriculum ideological and political in modern physics experiment course，which involves many teaching links and teaching contents，and excavates the ideological and political materials of experiment project deeply．Finally，this paper summarizes the role of curriculum ideology and politics in the five links of modern physics experiment course，and puts forward expectations for the“teaching”and“educating” functions of this course．

With the rapid development of China's electric power industry ,the renewable energy ,e.g.,wind andsolar energy,has rapidly   developed.However,the uneven spatial distribution and the supply instability greatlrestrict the development of new energy technologies. Focused on the development of gravity energy storage( CES) technologies ,it introduces four kinds of new grid-level gravity energy storage technologies emerging inthe world in recent years,including Gravity Power CES in USA,Ares Mountain GES in USA, Energy VaultCES in Swiss ,and Gravitricity CES in UK.Compared to the traditional electrochemical energy storage methodsuck kinds of CES technologies has the advantages of safety , large storage capacity and small impact on theenvironment.Also,they significantly reduce the dependence on geographical conditions and water resources.which are beyond the application of the traditional pumped hydro storage CES method.Thus , these new CESmethods have broad application prospects. According to the available researches, it also points out thedevelopment obstacles and technical problems of the new gravity energy storage technology ,which can providespecific guidance on the domestic development of GES technologies in China.

Under the background of new engineering and information technology, the reform objectives ofelectronic process teaching are formulated in response to the problems of single teaching content, lowefficiency,lack of relevance and lack of independent learning paths in traditional electronic process practiceteaching.The hybrid online and offline teaching model for electronics process training is proposed.Based on thecharacteristics of hybrid teaching, courseware ,micro-videos and exercises are produced,and the teaching of thelaboratory course is developed around three teaching stages: before , during and after class. The applicationexperience of this model proves that it can effectively mobilize students’interest in learning and practicalability of electronic technology, help teachers to grasp the teaching quality in a data way and achieve goodteaching effect,which can provide some reference for related practical teaching.

In order to further study the motion laws of the particle on the semi-cireular orbit,the whole motion ofthe small ball as a particle,from the entrance of a vertical and smooth semicircle inner track to the landing point ,isdiscussed.By mathematical method ,the dimensionless conditional factor related to the initial velocity is delined .andthe conditional factor is used as the independent variables to analyze the four phvsical quantities -the motion timefor the ball to adhere to the track ,the fight time in the air , the maximum rising height and the maximum horizontarange.Analysis reveals that under all possible values of initial velocity, the expressions for these four physicaquantities are all related to the conditional factor.This mathematical analysis provides a detailed deseription of themotion laws of particles on a semicireular inner track model, and its results can offer theoretical support forteaching,research ,and applications related to the semicircular inner track model of particles.

This paper first summarizes the improvement of the structure of the speetrometer,which reduces thedamage rate of each component, and improves the maintenance eficieney of the instrument and the accuraey ofdata reading.This paper further introduces the researeh and development of dual-optical spectrometer and itsdigital teaching system, which not only improves the effieieney of teachers’experimental guidanee, but alsoimproves the teaching quality of the spectrometer platform as a whole, and provides references for theimprovement of teaching quality in the field of spectrometer and other experimental practice fields.

The output voltage of the force sensor is an important parameter to be measured in the experiment ofmeasuring liquid surface tension coefficient by pulled off method. lt is very important to understand theexperimental principle and improve the accuracy of the experimental measurement.lt focuses on the study of thestate of the ring and the liquid film ,the change of force and the change of voltage with the height of the liquidhilm carried out by the ring during the measurement process,based on the experimental principle of measuringliquid surface tension coefficient by traditional pulling method.Finally,the selection of voltage measurementpoint in the experiment is clarified, the theoretical analysis formula is modified and the experiment ayerification is carried out.The verification results show that when the sling is in the critical state , the sensoroutput voltage U, should be selected as the maximum value of the voltage reading,which is more consistentwith the experimental principle.Moreover,the quality of the liquid film can not be ignored and should beincluded in the theoretical analysis and calculation to get more accurate results.The research results canprovide analysis ideas and reference for the course teaching of this experiment.

The construction and development for elective courses of new engineering disciplines is discussed inthis paper,based on the general education thinking, and with “ Nano Materials and Devices” as an example. The course construction goals should be enriched and clarified, according to the academic and industrialdevelopment.The course knowledge systems should be reasonably derived. The course content should beorganized logically , distinctively and with an overall consideration. Intellectual education should be wellcombined with moral education by a multi-dimensional ideological and political teaching strategy ,for elevatingthe course education level. Furthermore, the course should be continuously improved to minimize the gapbetween “ teaching" and “learing” gradually, and better support student development.

Physics experiment competition is an effective way to cultivate students’higher-order thinking and innovative ability．It used the lag sequence analysis method to analyze the learning behavior of the participants in the Excellence Cup College Physics Experiment Competition，compared and analyzed the results of the expert review，and constructed a competition-teaching combination learning behavior sequence suitable for innovatively designed physics experiment competitions．The research methods and strategies can help teachers to objectively understand the learning goals and learning behavior characteristics of participating students，thereby improving the pertinence and effectiveness of the guidance for students’innovative practical activities．