In the next semester, I completed the course of college physics experiment (I). Physics experiment is the basis of physics learning. Although in many physical experiments, we only reproduce the principles and results of theoretical knowledge learned in class, this process is consistent with the physical experiments conducted by physicists in the scientific study of molecular and material changes. In physical experiments, there are many factors that affect the phenomenon of physical experiments, and the phenomenon of physical experiments is also very complicated. By carefully designing the experimental scheme and strictly controlling the experimental conditions, teachers present physical problems in the best experimental way, so that we can successfully solve the problems in physical experiments, test our practical ability and comprehensive ability to analyze and solve problems, and deepen our understanding of relevant physical knowledge. I learned a lot through a semester's course.
When doing college physics experiments, it is very necessary to preview carefully before class in order to complete the experiments quickly and efficiently within the specified time and achieve good experimental results. First, review the relevant theoretical knowledge learned according to the experimental topics, clarify the whole process of the experiment according to the relevant contents of the experimental teaching materials, understand the purpose and basic principles of the experiment, and understand the key and success of the methods adopted in the experiment; Think about the relevant experimental instruments that may be used in the experiment, compare the experimental instruments listed in the textbook, and understand the working principle, performance and correct operation steps of the instruments, especially pay attention to those items that may cause damage to the instruments. Then we have to write a preview report, which can help us complete all the operations in the experiment smoothly. When writing a preview report, we generally include the experimental purpose, basic principles, experimental instruments, operation steps, measurement contents, data tables, preview questions and so on. The data table is closely related to the operation steps, and the column arrangement order in the data table should reasonably match the order of the operation steps. In this way, the data can be filled into the table in sequence at any time, and the regularity of the data can also be observed and analyzed at any time. At first, we didn't pay attention to the data table in the preview report and recorded the data on a piece of paper casually. Results We found that there would be a lot of confusion and mistakes when sorting out the data, especially when there were a lot of data, such as the experiment of measuring the Style elastic modulus of solid materials by dynamic vibration method, because the table was not designed in advance before the experiment, the data records were random and messy, which was very difficult to handle. Later, I learned a lesson and designed a data table according to the physical quantities and experimental steps to be measured before the experiment, which made it much easier to record the experiment and process the data. Experiments have taught us to form good habits of scientific experiments. The purpose of previewing thinking questions is to deepen the understanding of experimental contents or key issues and broaden our horizons. Thinking carefully and answering these questions before the experiment is helpful to improve the quality of the experiment. You can discuss with your classmates the problems or places you don't understand in the experimental principle or consult relevant materials. You can take what you really don't understand to the classroom and ask the teacher. Only by clarifying all the places in the experiment can we achieve the desired effect.
Preview is the necessary work before doing the experiment, but the main work of doing the experiment is classroom operation.
Classroom operation requires us to strictly abide by the principles of experiments, put the instruments in a reasonable position, make them easy to use and ensure safety. For example, the output button of high-voltage power supply should be far away from the operator. Equipment that needs to be operated or adjusted frequently should be placed in a position convenient for operation. Some electrical experimental instruments have many parts. First of all, we should put these instrument parts in proper positions and then connect them. During the experiment, the operating requirements of experimental instruments should be strictly followed, and all instruments should be adjusted to the correct position and stable state. When installing and adjusting the instrument, don't use unstable books as cushions, otherwise it will easily lead to the dispersion of measurement data, affect the experimental quality and damage the experimental instrument. In this process, there are often some faults or observed experimental phenomena are inconsistent with theoretical phenomena. First, we should seriously consider and check whether the experimental instrument is used and whether the circuit connection is correct, and correct it in time. If you can't solve it by yourself, you should ask the teacher for guidance in time, and you must not perfunctory. There is also reading, which requires enough patience and care, especially for some instruments with high precision. Reading must be carried out according to the correct reading method and must be careful. For the record of data, we should have the original data record, which is the basic information to record the whole operation process of physical experiments. Moreover, we must carefully observe the experimental phenomena and record them truthfully during the experiment. If it is found that the experimental phenomenon is inconsistent with the experimental theory, or the test results are abnormal, it is necessary to carefully check the reasons and redo the experiment carefully. After the experiment is completed, all experimental instruments should be restored to their original positions, and the experimental platform should be carefully cleaned.
After the experimental operation is completed, the experimental data should be carefully processed. Experimental data is the basis of experimental quantitative analysis and the first-hand information for exploring and verifying physical laws. When the systematic error is certain, whether the experimental data is properly processed will directly affect the size of accidental error. Therefore, the processing of experimental data is one of the important contents of experimental review. In this semester, we learned the methods of data processing:
1. average method is a commonly used data processing method to reduce accidental errors. Usually, under the same measurement conditions, the results of multiple measurements of a physical quantity will not be exactly the same. It is the best approximation of the true value to use the arithmetic average of many measurements as the measurement result.
2. Listing the data in the list method experiment can concisely express the relationship between related physical quantities, which is convenient for checking whether the measurement results and operations are reasonable and helpful for finding and analyzing problems. The list method is also the basis of the image method.
The following points should be paid attention to when listing: ① The table should directly reflect the relationship between related physical quantities. General independent variables are written in the front and dependent variables are written in the back, which is convenient for analysis. (2) The table should clearly reflect the number of measurements, the names and units of measured physical quantities, and the names and units of calculated physical quantities. The units of physical quantities can be written in the title bar, and generally do not appear repeatedly in the numerical column. ③ The data listed in the table should correctly reflect the significant figures of the measured values.
3. Drawing method selects appropriate independent variables, and through drawing, we can find or reflect the changing relationship between physical quantities, which is convenient to find out the law and determine the functional relationship of corresponding quantities. Drawing method is one of the most commonly used experimental data processing methods.
The requirements for drawing an image are as follows: ① Choose the coordinate axis according to the measurement requirements, generally taking the horizontal axis as the independent variable and the vertical axis as the dependent variable. The coordinate axis should indicate the name and unit of the physical quantity it represents. ② The scale of the coordinate axis should be selected properly, so that the measured data can be accurately reflected on the coordinate axis. In order to avoid a large blank on the drawing, the coordinate origin can be zero or non-zero. The estimated reading of the division of the coordinate axis should correspond to the estimated reading of the measured value (i.e. the last significant digit).
We also learned to process data by computer this semester. It is convenient and quick to process data by computer, which can save a lot of time and be clearer. However, the premise of computer processing is still that we are familiar with theoretical knowledge, the experimental operation process must be completed carefully, and the recorded data is accurate and effective.
Writing experiment reports and discussing problems are also indispensable links in college physics experiments. The experimental report is an exercise of our hands-on ability, writing ability and summing-up ability, and it also promotes us to think more deeply about the experimental process and conclusion. Our experimental report should include experimental phenomena and their explanations, problems encountered in the experiment and their solutions, records of experimental data, calculation and final results of data, verification of whether they are consistent with theoretical values, size of errors, final conclusion, discussion of experimental ideas, results of discussion and summary of experiments. A serious and high-level experimental report can also be regarded as a satisfactory conclusion for this experiment.
"Strengthening foundation, attaching importance to application, developing thinking, cultivating ability and improving quality" is the guiding ideology of college physics experiment. The purpose of college physics experiment is to deepen students' understanding of relevant physical knowledge, cultivate students' correct habits of scientific experiments, and improve students' hands-on ability, observation and analysis ability and innovation ability. Taking college physics experiment class is an exercise of personal ability. It not only exercises our carefulness and patience, but also helps me to develop good study habits and rigorous study attitude. This semester's physics experiment class has benefited me a lot. But I still have many shortcomings to correct. For example, the speed of doing experiments is very slow, so we will take this course next semester. I must pay attention to improve slowly in the future course study.