Activity 1: Add physics experiments to the 100 meter race.
After learning the "average speed" in senior one, in order to let students better understand the concept and physical meaning of the average speed, especially how to calculate the value of the average speed, I cooperated with the PE teacher and tried an interesting extracurricular experiment to measure the average speed in the 100-meter race. The specific process is as follows:
1. Organize students' preparation: make clear the content, purpose and task of this activity, and guide students to design the methods, steps and equipment of this experiment through discussion. During the discussion, the students decided two schemes: one is to divide the whole process into several sections (for example, five sections, each section is 20 meters), measure the time spent in each section, and then find out the average displacement speed of each section for analysis and comparison; The second is to divide the time into several segments and measure the displacement of each segment, so as to find out the average speed of each segment at different times and make analysis and comparison. Everyone agrees that the latter method is difficult to control, but in order to achieve the goal more accurately and comprehensively, we still decide to proceed separately according to the two schemes. Divide students into groups, assign tasks and prepare equipment (stopwatch, tape measure, flag, etc. ) separate, contact the physical education teacher and arrange the time and venue.
2. Organize students' experimental tests: Divide students into several groups, with 5 people in each group, and conduct them according to the above two schemes respectively. In the experiment, each group cooperated with each other, that is, one group ran 100 meters in turn as the tested group, and the other group was responsible for judging, timing and recording as the test group, and then the two groups returned in turn. For example, according to the first scheme, the runway is divided into five sections, and flags are inserted as signs. Students in the test group stand in front of the sign and prepare for recording. After the students are ready, the teacher blows the whistle to remind them to start, and the students in charge of the test start to record the time at the same time. When the tested students pass their positions, they stop to record the time and summarize the records, and then the next student continues the test.
3. Organize students to process, analyze and discuss data: According to the data measured in the experiment and the knowledge learned, each student can calculate his average speed in each displacement (or each time period) and discuss accordingly, such as whether his average speed in each displacement (or each time period) is equal. Is the average speed of different students equal in the same displacement (or time)? Can the average speed be reflected in the speed of running with classmates? How can we describe the speed of movement more accurately? ......
Through the above lively extracurricular experiments, students not only deepen their understanding and mastery of what they have learned, but also cultivate their own experimental ability, organizational ability and scientific thinking and analysis ability. For senior one students, combining unfamiliar and abstract physical problems with familiar and vivid physical activities will not only make the learning process interesting, but also make monotonous and tiring physical exercise easy, vivid and meaningful, easily stimulate students' interest, enable them to master knowledge in active "practice", exercise at the same time, and enhance their physical quality. In addition, in this activity, I just ask for a little guidance. From planning, preparation to organization and implementation, students basically have to do it themselves, which not only cultivates students' organizational management ability, but also strengthens their collectivism thought of unity, cooperation and mutual help in the activity.
Activity 2: Measure the acceleration of gravity as much as possible.
After learning the mechanics knowledge of senior one, I arranged an extracurricular activity for the students: please use the mechanics knowledge you have learned to design several methods to measure the acceleration of gravity, do it yourself, compare the results, analyze the causes of errors and improve measures. As soon as the topic came out, the students became active. They actively searched for information, tried their best to communicate and discuss with each other, and comprehensively applied the newly learned mechanical knowledge to design various schemes, which were realized one by one, mainly including:
Method 1: according to g = mg, as long as the gravity g and mass m of a given object are measured, it can be obtained from g = g = g=G/m m ... This method is simple in principle and practical operation, but it can't be accurately measured under the condition of middle school, resulting in a large error, but it is also a simple and easy method.
Method 2: Using the knowledge of free fall, measure the falling height H and falling time T, and get g=2h/t2 according to the formula h= gt2 /2. In the actual experiment, students boarded the four-story teaching building and measured the height (falling height) with a tape measure; When measuring the falling time, we also designed various methods: some students put an iron plate on the ground, started to start the stopwatch timing when they released the heavy objects from upstairs, and ended the timing when they heard the sound of the heavy objects hitting the iron plate, and some students designed ingenious electromagnetic relay devices to automatically control the timing. This experiment is easy for students to understand, so they show great enthusiasm and the experiment is very energetic. At the same time, they also imitated the leaning tower experiment of Pisa to verify that different objects landed at the same time. However, the inevitable air resistance, timing error, height measurement error and other factors in this experiment will affect the accuracy of the measurement results.
Method 3: Using the experimental device of "Verifying the Law of Conservation of Mechanical Energy" in Experiment 4 of Senior One Physics Students, imitating the experimental principle of "Measuring the Acceleration of Uniform Acceleration Movement" in Experiment 3, the displacement difference Δ s of the free drop hammer in the continuous equal time interval t is measured, and then G can be obtained from the formula g = Δ s/t2. This experiment comprehensively uses the experiments of two students, which shows the students' ability to master, synthesize and flexibly use what they have learned. This experiment will also produce great errors due to friction.
Method 4: Measure with the simple pendulum period formula. There was a student experiment in the textbook of this method, but the students were not satisfied. They actively used their brains and made many improvements to the experiment, further reducing the errors and achieving good results.
This activity gave full play to the divergence of students' thinking, exercised their fluency, flexibility, comprehensiveness and creativity, showed their talents, and cultivated and improved their thinking quality to a certain extent.
Activity 3. Check the circuit fault with a multimeter.
After learning the knowledge of electricity, many students are puzzled: how can we combine what we have learned with practice? You can often solve a circuit problem skillfully, but when you encounter practical problems, such as troubleshooting the actual circuit or installing a simple application circuit, you feel at a loss. 1997 there is a multiple-choice question in the physics exam of the college entrance examination, which is 14. Check the position of the broken line in the circuit with a multimeter. The original title is:
One of the three wires in the illustrated circuit is broken, and the power supply, resistors R 1, R2 and the other two wires are all good. In order to find out the reason for the disconnection, some students want to connect the red probe of the multimeter to the positive pole A of the power supply first, and then connect the black probe to the B terminal of the resistor R 1 and the C terminal of R2 respectively to observe the indication of the multimeter pointer. Among the following file selections, those that meet the operating rules are: (Figure omitted)
A, DC 10V gear b, DC 0.5A gear
C, DC 2.5V, D, ohm.
This topic is novel in design and ingenious in conception, which organically combines physical knowledge with practice. It requires students not only to master the principle and knowledge of multimeter, but also to use it flexibly in practice. So we start with this problem, cooperate with the labor teacher, and arrange for students to learn the preliminary knowledge and technology of using multimeter to repair electrical appliances after class.
First of all, I asked the students to analyze, study and summarize what they had learned. The students quickly mastered the method in theory and made it clear that circuit faults can be easily detected by using the voltage, current, ohm or the combination of the three, but the principles, methods and precautions are different. Then we set up a lot of fault circuits in the laboratory, so that students can check and troubleshoot themselves. After repeated practice, students can skillfully combine theoretical knowledge with practical operation, and then we will send the collected faulty small appliances such as radios, tape recorders and telephones to everyone, so that they can learn to repair faults by combining the electronic technology knowledge they have learned in labor technology classes. The students are very interested, but they also encounter many difficulties. To this end, many students actively learn electronic technology, radio and other knowledge, master welding, assembly and other technologies to overcome these difficulties. They all jumped for joy when they saw the repaired small radio.
This activity lasted for a long time, from learning knowledge and practicing methods to practicing maintenance. The first radio was repaired for more than a month, during which it was really difficult. However, the students kept a high interest, kept learning and exploring, and kept overcoming difficulties until they succeeded, showing their strength and perseverance. Several students even became "masters" in maintenance. They have been able to skillfully eliminate some small circuit faults, and they also use their own technology to actively and enthusiastically serve everyone. They have made outstanding achievements in learning from Lei Feng, and they have become role models for helping others and cultivated their good ideological and moral qualities. In addition, this activity also permeated the popular concept of "STS" education, closely combined discipline theory, science and technology with social life, and played an important role in learning knowledge, cultivating ability, stimulating interest and improving students' comprehensive quality.
Activity 4. Seven beautiful colors
In optics, we know seven colors of light: red, orange, yellow, green, blue, indigo and purple. Through the dispersion of light, we observed this beautiful seven-color light. In the interference and diffraction of light, students have a further understanding of it. Everyone is curious about these gorgeous seven colors. I took the opportunity to encourage students to explore the mystery deeply, and asked them to solve their doubts through extracurricular observation, experiments and access to relevant materials. Students' knowledge, thinking, interest and imagination have been greatly improved in the activities. They read many popular science magazines and books, such as Science and Technology in Middle School, We Love Science, Knowledge is Power and related optical books, and made careful notes on relevant contents. They carefully analyzed several experiments and improved them, and successfully made experiments such as observing solar spectrum, artificial rainbow, thin film interference and single slit diffraction. As required, the students wrote down all their knowledge. Some students are very interested in dispersion phenomenon. They analyze and discuss rainbow, neon, sunset and China phenomena in the atmosphere. Some students talked about their own views on the interference and diffraction of light and its application; Some students have learned about high and new technologies such as holographic technology and laser technology and have shown great interest, and are determined to learn optical knowledge well and make contributions to the modernization of the motherland. More students have not only learned knowledge and broadened their horizons, but also felt the beauty of physics, science, nature and human wisdom, thus cultivating their sentiments and cultivating their comprehensive aesthetic qualities of appreciating beauty, expressing beauty and creating beauty.
In short, extracurricular sports activities combine the physical knowledge learned in class with practice, which is both interesting and scientific. It not only develops students' intelligence factors, but also helps to improve non-intelligence factors. At the same time, it also greatly enriches students' extracurricular life, so that they will not be idle after "reducing the burden", thus truly achieving the purpose of "reducing the burden" and improving students' comprehensive quality in an all-round way.