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- Teaching practice of the photon gas blackbody radiation theory for optoelectronics major
- CHEN Pei-feng, WANG Ming-hai
- College Physics. 2023, 42(9): 1. doi:10.16854/j.cnki.1000-0712.220530
- Abstract ( 300 ) PDF (750KB) ( 578 )
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- Energy band structure of tightly bound electrons in hexagonal close-packed lattice
- YU Feng-lian, HU Jian-min, WANG Yue-yuan
- College Physics. 2023, 42(9): 5. doi:10.16854/j.cnki.1000-0712.220595
- Abstract ( 367 ) PDF (684KB) ( 533 )
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- A Property of node acceleration on gear transmission
- LU Hai-xiang, SU Zhen-chao
- College Physics. 2023, 42(9): 8. doi:10.16854/j.cnki.1000-0712.220614
- Abstract ( 277 ) PDF (869KB) ( 487 )
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- Analysis of planetary motion with complex vector equation
- PENG Ding-hui
- College Physics. 2023, 42(9): 12. doi:10.16854/j.cnki.1000-0712.220604
- Abstract ( 364 ) PDF (736KB) ( 528 )
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- Derivation of the conservation laws of electromagnetic field using the index notation
- LI Zhao-yu
- College Physics. 2023, 42(9): 16. doi:10.16854/j.cnki.1000-0712.220460
- Abstract ( 260 ) PDF (517KB) ( 396 )
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- A method of introducing the expression of coordinate operator in momentum representation
- FENG Xiu-rong, WANG Feng
- College Physics. 2023, 42(9): 20. doi:10.16854/j.cnki.1000-0712.220523
- Abstract ( 486 ) PDF (492KB) ( 426 )
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- Quantum nonlocality and Bell inequality
- ZHOU Jiang
- College Physics. 2023, 42(9): 23. doi:10.16854/j.cnki.1000-0712.220517
- Abstract ( 328 ) PDF (646KB) ( 283 )
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- Analysis on interferential images in the experiment of measuring the focal length of thin convex lens by auto-collimation method
- YU Cui-ling, JIANG Xiang-qian, YAO Feng-feng, LUO Su-hua, LIN Shan, WU Da-kun
- College Physics. 2023, 42(9): 28. doi:10.16854/j.cnki.1000-0712.230070
- Abstract ( 383 ) PDF (688KB) ( 620 )
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- What kind of enlightenment can we get from the mistakes of physics masters?
- ZHAO Song-nian, YU Yun-xian
- College Physics. 2023, 42(9): 31. doi:10.16854/j.cnki.1000-0712.220534
- Abstract ( 349 ) PDF (850KB) ( 525 )
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- Figures of merit optimization for reversible simple air refrigeration cycle
- WU Bo-wen, CHEN Lin-gen, YIN Yong, GE Yan-lin,
- College Physics. 2023, 42(9): 40. doi:10.16854/j.cnki.1000-0712.220304
- Abstract ( 184 ) PDF (622KB) ( 164 )
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- A brief discussion on the exploration and practice of ideological and political in thermotics
- HAN Wen-juan, LIU Hai, QIANG Rui
- College Physics. 2023, 42(9): 44. doi:10.16854/j.cnki.1000-0712.220489
- Abstract ( 412 ) PDF (899KB) ( 850 )
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- Simulation of gravitational lensing based on coordinate transformation
- CHEN Pin-jian, LIU Hai-cheng, LI Xiang-hua
- College Physics. 2023, 42(9): 52. doi:10.16854/j.cnki.1000-0712.220382
- Abstract ( 332 ) PDF (1353KB) ( 349 )
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- Simulation analysis of ultrasonic cavitation effect pressure
- GAO Jin-ze, HUANG Fei-jun, HAN Run-ze, ZHANG Hao, JING Peng-fei
- College Physics. 2023, 42(9): 60. doi:10.16854/j.cnki.1000-0712.230012
- Abstract ( 381 ) PDF (802KB) ( 419 )
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The concepts of blackbody radiation and stimulated radiation are very basic for students majoring in optoelectronics. Introducing these concepts through the teaching of photon gas chapter in statistical physics course systematically is very important for their acquisition of professional knowledge comprehensively. We introduce the teaching process summarized through practice, and analyzes some details concretely.

The tight bound electron model is used to calculate the energy band of hexagonal close-packed lattice. The results show that the energy band of hexagonal close packed lattice is of a special complex form, and the reason for the formation of the complex energy band is that its unique lattice structure leads to the symmetry breaking of neighboring atoms. On the plane of reciprocal space kz=0, the real part is symmetric about the kx axis and the ky axis, while the imaginary part is only symmetric about the ky axis and asymmetric about the kx axis, which is determined by the asymmetry of the next nearest neighbor atoms of the hexagonal close-packed lattice in the rectangular coordinate space. The relevant research results are not only the expansion of the teaching content of solid physics, but also provide a theoretical basis for analyzing the relevant physical properties of crystal materials.

A kinematic problem on gear meshing transmission is introduced, and solved in detail by geometric and analytical methods. The errors in the original solution of the problem are pointed out. It is proposed that an important acceleration property of nodes in cylindrical gear transmission is that the projections of nodes’ acceleration on the direction of common tangent of nodes are equal whether the motion of the gear or rack is rotation about a fixed-axis or general planar motion.

For the problem of planetary trajectory in a centered force field, it is solved by establishing equations with complex vectors as variables. In the process of solving, not only the general law of planetary motion is obtained, but also the speed formula of the planet and Hamilton's theorem are derived, and the second focus position of the planetary orbit and the trajectory based on the Laplace-Runge-Lenz vector are found, and thus the trajectory envelopes of satellites launched in different directions are obtained.

This paper uses the index notation to derive the laws of conservation of energy, momentum and angular momentum of the electromagnetic field, which is characterized by clear physical ideas and unequivocal direction of derivation; natural introduction and intelligible meaning of physical quantities; convenient mathematical operations and relatively low difficulty.

In the textbook of quantum mechanics, the expression of coordinate operator in momentum representation only gives the final result, and the detailed derivation process is seldom mentioned, which will cause students to have corresponding doubts in the process of learning quantum mechanics. What is more,the expression of coordinate operator in momentum representation is deduced by using the basic assumption that free particle is plane waves and Dirac δ function, which is abstract and complex, and is not conducive to students in-depth understanding in the teaching process. In this paper, we introduce the concept of Taylor's translation on the basis of Taylor's expansion. According to the commutation relation and Taylors translation, the expression of coordinate operators in the momentum representation is derived. This method is enlightening in the teaching process and more conducive to the students understanding of this part of the content.

In 2022, the Nobel prize in physics award researches on the nonlocal quantum entanglement and basic test of Bell inequalities. Under this background, this paper aims to analysis various non-locality in quantum mechanics, to derive the Bell inequality satisfied by conditional probability, and further to understand the nature of violation of Bell inequalities in quantum mechanics．

Several interferential images are shown in the experiment of measuring the focal length of thin convex lens by auto-collimation method, including the direct reflection imaging of the rear surface of convex lens. It is found that an isometrical and handstand interferential real image is obtained by adjusting the position of convex lens and plane mirror. However, the brightness of the interferential image is weaker than that of the image achieved by auto-collimation method. In this paper, the imaging principle of the interferential image is explained by analyzing the multiple imaging process.

In the process of the development of physics, some scientific celebrities often make mistakes in judgment in the face of new concepts and new discoveries, which brings irreparable losses to the younger generation of researchers, and some misjudgments will hinder the scientific progress at that time. Usually, for this kind of situation, which is not uncommon in the history of science, the relevant documents or biographies are mainly analyzed from the aspects of methodology and epistemology, and sometimes they are also limited by factors such as the potential psychology and habits that are taboo to celebrities, and seldom conduct in-depth analysis. In fact, we can not expect to try to change the behavioral habits and mindsets of scientific masters, famous experts or authorities through so-called methodological or psychological analysis; instead, we hope that young scientific and technological personnel will realize what kind of actions they need to take when facing such mistakes. A way is desirable so as to at least reduce the possible losses. Different from this, this paper selects some physicists who have made misjudgments about new concepts and new experimental results due to their personal styles and professional backgroundssince the founding of quantum mechanics, causing the young people they work with to miss important discoveries. Opportunity, it must be said that it is a very regrettable thing. Is it practical to discuss these cases now? Science is developing, and new phenomena and concepts will continue to emerge. It is difficult to avoid similar situations. What enlightenment will it bring to the parties? What can we learn from such mistakes? Whether it is a scientist, a mentor or a younger generation of scientific researchers who are already in high scientific research positions, reading the mistakes of the masters of physics will surely learn valuable lessons and get profound enlightenment; importance and implement it in their own research work.

In this paper, a reversible simple air refrigeration cycle is studied by using classical thermodynamics, and the figures of merit proposed by finite time thermodynamics is used as the optimization objective. Through theoretical analysis and numerical calculations, the analytical formulas between figures of merit and influencing parameters are derived. By optimizing the pressure ratio, the optimal performance of the refrigeration cycle is given. The influence of cycle temperature ratio on the optimal performance of refrigeration cycle is analyzed. The results show that when the figures of merit is selected as optimization objective for performance optimization, there is an optimal pressure ratio to make the figures of merit get the maximum value. Moreover, the optimization results ensure the coordination between the cooling load and COP, which is a better compromise plan.

The exploration and practice of ideological and political of thermotics are introduced. Firstly, the constructing background of ideological and political of thermotics are introduced. Then the idea and objectives, the past teaching problems, the corresponding teaching strategies, the excavation and addition, the implementation and effect of ideological and political in thermotics are listed. How teachers can do a good job in ideological and political of thermotics is set forth. Some reference suggestions are provided for teachers to do well in their ideological and political of professional courses.

The deflection of light in the gravitational field is one of the predictions of the general theory of relativity．The gravitational lensing effect refers to a series of observation effects caused by the bending of light emitted by the light source due to the gravitational field of the massive object between the distant light source and the observer，which is of great importance in the research of astrophysics，cosmology and other fields．In this paper，the simulation of gravitational lensing based on coordinate transformation is mainly introduced．Two lens models are considered for the foreground lens，and the corresponding lens equation and the expression of deflection angle are presented．Then we discuss three different surface brightness profiles of the background light source under the same lens model，and the corresponding lensed images are generated by computer

In this paper, the impulse pressure distribution in the ultrasonic water bath with a thin tube is mainly explored and the ultrasonic capillary phenomenon is explained. The reasons for the rise of the liquid level in the tube are the impulse pressure generated when the cavitation bubble generated by the surface tension and cavitation effect collapses. We simulated the distribution of ultrasonic sound pressure in the water bath by COMSOL, calculated the cavitation bubble radius and its change rate with time under different sound pressure amplitude conditions based on MATLAB, and calculated the magnitude of the impulse pressure in integration. In the experiment, by changing the position of the bottom of the thin tube, the influence of the punching pressure on the rising height of the liquid level was explored, and the ultrasonic capillary phenomenon was well explained compared with the theoretical curve, and the experimental results were consistent with the ultrasonic cavitation theory.