Research On System Error Analysis And Improvement Method In High School Physics Typical Experiments

The curriculum standard of general physics formulated by the state in 2017 condenses the core accomplishment of physics,which includes four aspects: physical concept,scientific thinking,scientific inquiry,scientific attitude and responsibility.Experiments are an important means of physics learning and an important way to cultivate students' physical discipline literacy.Experiments are also an important part of basic physics teaching and a research means of physics.Physical experiments can help students better understand the laws and phenomena of physics,enable students to acquire perceptual knowledge,thus stimulate their interest in learning,and can be cultivated in the process.Students' experimental operation ability,comprehensive analysis ability and thinking innovation ability.In the middle school physics teaching process,the results of the experiment often differ greatly from the expected values or results.For example,when students explore the current relationship of series-parallel circuits,they find that the sum of the current values of each branch is greater than that of the trunk circuit,and the same conclusion has been reached in many measurements.Teachers often say "This is an experimental error" and pass it lightly.Such treatment not only does not deepen students' understanding of the principles of physics,but also causes confusion.In teaching,we find that if we can use the facts of these errors to make students deeply analyze and explore,we can not only make students better understand the principles of physics,but also enhance their confidence in the exploration of nature.In this paper,several typical experiments in high school physics are explored from the angle of error analysis and experiment improvement.Taking the experiments of "verifying Newton's second law" in mechanics experiment,the experiments of "measuring resistance by volt-ampere method","measuring power supply electromotive force and internal resistance" in electrical experiment as examples,the systematic errors are carried out by formula analysis method,experimental comparison method,U-I image method,equivalent power supply method,etc.The reasons for the deviation of the experimental results are found through analysis.From the aspects of feasibility,operability,requirements of experimental equipment and errors,we pursue rationaland implementable experimental improvement schemes,and strive to weaken or eliminate and correct systematic errors,so that students can better understand the relationship between theory and experiment.In the experiment of "verifying Newton's second law",the author provides an experimental improvement scheme from the perspective of experimental equipment,data measurement,research methods and force measurement tools.In the experiment of measuring resistance by volt-ampere method,starting from the unconventional use of ammeter,according to the different objects to be measured,various improvement schemes are provided.For example,the innovative use of ampere method in measuring voltage of ammeter,and the half-bias method is suitable for measuring internal resistance of ammeter,etc.In the experiment of "measuring power supply electromotive force and internal resistance",based on the idea of equivalent power supply method,the source of measurement error and the specific relationship between measurement value and real value are clarified.The internal and external connection method of ammeter is used together,and the system error is eliminated by using modified formula through experimental data.Through sorting out several typical experiments in middle schools,the inappropriateness of design principles and experimental designs in each experiment is analyzed.(Simplification,imprecision,etc.)bring about systematic errors,put forward correction programs or formulas,and give the appropriate teaching design.Through teaching cases,create physical scenarios,design physical problems,guide error analysis ideas,discuss experimental improvement programs,arrange group cooperation experiments,and compare the experimental results.Combining theory with practice through teaching practice,practice in turn verifies the feasibility of improving the experimental scheme.In the process of teaching implementation,all kinds of possibilities encountered will be transformed into generative teaching resources.The possible factors causing errors will be explored by using the results of errors.The interference factors of errors in experimental results will be changed into positive factors to improve teaching effect and teaching strategies.Finally,a suitable,operable,efficient and universal teaching reference will be formed.In the limited experimental classroom teaching,it not only improves the teaching effect,but also creates infinite possibilities.