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- Concerted construction of undergraduate and graduate courses of computational physics
- LU Guang-hong, LIANG Lin-yun, JIANG Yin, ZHOU Hong-bo, HU Di, ZHU Li-hua, GENG Li-sheng, MAN Xing-kun, LI Bo, ZHOU Miao, ZHANG Yu-jie, LIU Li-min, JIN Shuo, SONG Chun-yan, ZHANG Ying, SHU Xiao-lin
- College Physics. 2022, 41(1): 1. doi:10.16854 / j.cnki.1000-0712.210162
- Abstract ( 883 ) PDF (330KB) ( 527 )
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- Attracting and repelling of matter wave solitons by external potentials
- WANG Yan
- College Physics. 2022, 41(1): 8. doi:10.16854 / j.cnki.1000-0712.210191
- Abstract ( 686 ) PDF (311KB) ( 411 )
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- The tidal force related to the moon
- JIN Xian-yi
- College Physics. 2022, 41(1): 11. doi:10.16854 / j.cnki.1000-0712.210110
- Abstract ( 1003 ) PDF (203KB) ( 868 )
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- Study and numerical simulation of quantum tunneling for one-dimensional double square potential barriers
- LI Hai-feng, WANG Xin-mao
- College Physics. 2022, 41(1): 15. doi:10.16854 / j.cnki.1000-0712.210279
- Abstract ( 1461 ) PDF (305KB) ( 540 )
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- Visualization research on the quantum properties of N-dimensional potential box functions
- ZHENG Xing-rong¹, ZHENG Yan-fei²
- College Physics. 2022, 41(1): 19. doi:10. 16854 / j.cnki.1000-0712.210250
- Abstract ( 963 ) PDF (436KB) ( 885 )
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- Some problems in the teaching of special relativity
- WANG Lei
- College Physics. 2022, 41(1): 24. doi:10.16854 / j.cnki.1000-0712.210190
- Abstract ( 866 ) PDF (273KB) ( 472 )
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- Collision test of pure rolling double steel balls on wide and narrow rails
- LU Jun-ling, GU Chen, REN Nai-jing, MA Bo-yi
- College Physics. 2022, 41(1): 27. doi:10.16854 / j.cnki.1000-0712.210184
- Abstract ( 1020 ) PDF (296KB) ( 352 )
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- Systematic error analysis of period of simple pendulum
- SHAO Yun
- College Physics. 2022, 41(1): 32. doi:10.16854 / j.cnki.1000-0712.210247
- Abstract ( 3869 ) PDF (353KB) ( 1001 )
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- Design and simulation of fingerprint lock based on optical holography
- YAN Ai-min, HU Zhi-juan
- College Physics. 2022, 41(1): 39. doi:10.16854 / j.cnki.1000-0712.210214
- Abstract ( 669 ) PDF (333KB) ( 186 )
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- Exploration and practice of student-centered college physics teaching
- GAO Lan-xiang, XU Dan-hua
- College Physics. 2022, 41(1): 43. doi:10.16854 / j.cnki.1000-0712.210218
- Abstract ( 637 ) PDF (522KB) ( 446 )
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- Design and practice of ideological education in college physics ———taking particle mechanics as an example
- LONG Xiao-yan¹, XIE Hai-yan², WU Shi¹, ZHANG Yi-xun¹, LI Jia-ding¹
- College Physics. 2022, 41(1): 50. doi:10.16854 / j.cnki.1000-0712.210166
- Abstract ( 2444 ) PDF (563KB) ( 817 )
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- Reform and exploration of college physics in architectural university under the background of new engineering education
- LIU Yan-ling¹, GU Jin-xia¹, LIANG Chun-tian¹, TIAN Wei¹, SONG Feng²
- College Physics. 2022, 41(1): 56. doi:10.16854 / j.cnki.1000-0712.210132
- Abstract ( 823 ) PDF (467KB) ( 1077 )
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- Analysis of the rotation modes of the coin under different conditions
- FANG You-le, WANG Tian-xiao
- College Physics. 2022, 41(1): 61. doi:10.16854 / j.cnki.1000-0712.210089
- Abstract ( 878 ) PDF (424KB) ( 328 )
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- Improvement of Helmholtz coil magnetic field measurement based on electromagnetic induction
- XU Lin-chao, XIANG Wen-li
- College Physics. 2022, 41(1): 68. doi:10.16854 / j.cnki.1000-0712.210195
- Abstract ( 1581 ) PDF (457KB) ( 770 )
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- Improvement and analysis of optical-fiber temperature sensor experiment
- RAN Lu, LIAO Hong-bo
- College Physics. 2022, 41(1): 73. doi:10.16854 / j.cnki.1000-0712.210258
- Abstract ( 739 ) PDF (558KB) ( 933 )
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- Monte-Carlo simulation of 2-D Ising model———application of Metropolis，Swendsen-Wang and Wolff algorithm
- XU Lin, CHEN Yu-ze, LIU Jia-hao
- College Physics. 2022, 41(1): 79. doi:10.16854 / j.cnki.1000-0712.210101
- Abstract ( 2212 ) PDF (336KB) ( 1191 )
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Computational physics，as the third method of studying physical phenomena and laws

alongside the- oretical and experimental physics，has become more and more important with

the rapid development of computer technology and continuous intercross of

disciplines. However， due to the relatively late development of computational physics

and some of its own discipline characteristics，there is no mature teaching system for under-

graduate and graduate courses. In this article the exploration andpractice of concerted

construction of undergraduate and graduate computational physics courses in Beihang University

are mainly introduced. Undergraduate course is positioned to master the basic theoretical

knowledge of computational physics as well as the case practice to solve physics

problems. The undergraduate course teaching is small-sized. The graduate course is positioned on

the solid professional basis and broad knowledge structure of computational physics，highlighting

the professional and cutting-edge of the contents，and emphasizing the importance of the practical ability and the independent

capability in sci- entific research. The graduate course offers parallel courses based on the student’s major. The exploration and prac- tice of concerted construction are carried out mainly from the course content，teaching method，and assessment method to ensure continuity and unity of graduate and undergraduate courses.

The theoretical results are presented using the Lagrange approach for matter
wave

solitons motion in some external potentials. The focus is the solitons with zero initial

velocity，which exhibit different behaviors in po- tential wells and barriers，and the results are

that the barrier repels solitons and the potential well attracts solitons. These conclusions are

verified by numerical simulation.

Starting from the simplified mechanical model of the earth-moon system，the dynamic

equations of the surface object in different coordinate systems are derived strictly，and through

the analysis of symmetry，the tid- al force is obtained，which is helpful to understanding of the

tidal force and the cause of tide.

Quantum tunneling effect has important applications in practical technology. In

this paper，it is shown how to calculate the transmission coefficients of one-dimensional

asymmetric and symmetric double square potential barriers with the arbitrary boundary.

Then we study the dependence of the transmission coefficients for symmetric double square

potential barriers on the barrier width，the spacing between the two barriers and the ratio of the

incident energy of microscopic particles to barrier height ( E / U₀) . Finally，the results show

that the transmis-sion coefficient decreases from the maximum value 1 to the minimum value 0 with the increase of the

barrier width. Moreover，the transmission coefficient oscillates periodically with the increase of

the barrier spacing. The analytical expression of the barrier spacing corresponding to the maximum

transmission coefficient is derived，and the period of oscillation is given，which is equal to

the de Broglie wave length of the microscopic particle. When the barrier width is

smaller，the transmission coefficient is easier to reach and keep the maximum value 1 with the

increase of E / U₀. When the spacing of the double potential barriers is larger，the oscillation

period of the transmission coeffi- cient is larger，while the oscillation amplitude becomes

smaller，with the increase of E / U₀. Therefore，the particle is easier to realize resonant

tunneling in this case.

Using quantum theory derivation and numerical calculation methods，the diagram and model

of one- dimensional potential box function are firstly obtained. Then the wave function，energy

level and probability density of N-dimensional potential box functions in quantum mechanics are

studied comprehensively and systematically. Fi- nally，all characteristics of the potential box

functions are simulated using MATLAB software. We find that the ener- gy of particles is quantized

and discontinuous in N-dimensional potential box. The quantum number n cannot be ze- ro，and the

higher the quantum number n is，the higher the energy level is，while the higher the mass

m is，the lower the energy level is. Generally，the larger one-dimensional potential box length a

is，the lower the correspond- ing energy level is. The number of nodes is N-1，and the more

the nodes are，the shorter the wavelength is，the higher the frequency is，the higher the energy

level is. For two-dimensional potential box function，the number of peaks is nₓ ×ny ，and the

intersection numbers of wave function and a plane of Ψ = 0 is nₓ ×ny ，too. For degeneracy， in

general，the degeneracy of particles in the two-dimensional potential box model is uncertain. But

for the two di- mensional square potential box function model，the energy level degeneracy of the

particles in the box can be divid- ed into general and special cases. The degeneracy of

three-dimensional potential box function are nx +ny +nz . The vi- sualization results are in

complete agreement with the theoretical results. Finally，the color function of MATLAB

software is firstly used to realize the four-dimensional representation，and the four-dimensional

slice diagram of the three-dimensional potential box function are obtained. The results of

this visualization are in complete agreement with the theoretical results，and it is also of

great significance for the understanding of the abstract concept.

This paper discusses several problems in the teaching of relativity，including

questions in common examples，convenient form of Lorentz transformation，discussion on the example

of simultaneous relativity in another frame of reference，the phenomenon of length measurement seen

in another reference frame，delay of time and the time of each point in the motion reference frame

are different，and a simple derivation of Doppler effect of light is preformed. Through the

discussion of different processes in different reference systems，master the method of discus- sing

problems in motion reference frame，and the different performance of the same process in

different inertial frames，the measurement results of all phenomena remain unchanged under Lorentz

transformation.

A pure rolling double steel ball collision experiment is carried out on a wide

and narrow horizontal rails，and it is found that it is significantly different from the double

steel ball collision experiment in sliding motion; the reason is that the collision of the pure

rolling double steel ball is the frontal and tangential collision at the colli- sion point. The

two types of collisions obey different dynamic laws; after a collision，the motion state of the two

steel balls is no longer pure rolling. To return to pure rolling，each steel ball must pass through

the interaction between it- self and the guide rail. The effect is to go through a self-adjusting

stage; the energy loss in the self-adjusting stage is related to the rolling radius of the steel

ball and the deviation of its immediate state from pure rolling.

This paper analyzes and calculates the influence of the pendulum angle，the rotation of

the ball，the mass of the suspension line，the air buoyancy and the air resistance on the period of

the pendulum one by one. Tak- ing a 1 m length and 5° swing angle small amplitude pendulum as an

example，the relative errors of the five factors are

+0.45‰，+0.02‰，-0.45‰，+0.07‰，-0.14‰，respectively，and the total is only -0.05‰，which means that the

five error factors almost cancel each other，and the systematic error of the small

pendulum experiment is very small in theory. This paper gives a more detailed

reasoning，calculation and analysis process，especially the reasoning process of air resistance

moment，as well as charts and tables，for providing a more complete and accu- rate

understanding. Finally，some necessary explanations are given in view of some possible deficiencies

in people's understanding of air resistance.

In this paper，we propose a fingerprint lock that combines fingerprint verification

and optical holo- graphic encryption. It is placed in front of the IC chip of the smart card to

pre-encrypt and authenticate the user's PIN code，and strongly enhances the protection of

smart-card. Actually，the proposed fingerprint lock uses the fin- gerprint image as the key and

records the angle multiplexing optical encrypted hologram in the photorefractive crystal

material. This kind of hologram is different from the traditional angle multiplexed volume

hologram. Its refer- ence light has both amplitude modulation of fingerprint image and random phase

modulation. It has the advantages of good privacy，convenient carrying and high security.

Numerical simulations confirm the validity and safety of pro- posed technique.

In order to solve the real problems of teaching college physics monotonously，and too much

emphasis on knowledge itself but not the ability and quality during the assessment，our teaching

paradigm has been changed from teacher-centered to student-centered. Based on the smart

classroom and the Wisdom Tree platform，a new smart learning environment of internet plus

education has been established. The physics curriculum has been inte- grated with the

ideological and political elements，resulting in a new knowledge-application cutting-edge-contentcurriculum system，which also highlights the feature of energy and power industry. It also encourages the student to construct the knowledge system independently and learn deeply by group teaching approach based on real tasks，as well as the emphasis on the individual learning experience. A comprehensive evaluation system has been built to promote the overall development of knowledge，abilities，and qualities of students. The design of the system is result-oriented，featured with a combination of both formative and summative，and of qualitative and quantitative measures.

It is of great significance and imperative to strengthen political and ideological

education in teaching. In order to deepen the teaching reform of college physics，the teaching

design of ideological education is carried out under the blended learning mode by using the

effective teaching method based on the traditional teaching and aiming at knowledge goal.

Through the design and practice of on-line，off-line and examination，combining the lec- ture of

ideological education by famous teachers，the course mode of ideological education is formed.

The applica- tion of this model takes the first chapter，particle mechanics，as an example. The

practice shows that the education quality is improved.

College physics is an important public fundamental and compulsory course for students

who major in science and engineering. In this paper，by combining the new engineering education

with times characteristic，col- lege physics teaching of Tianjin Chengjian university is taken as an

example. A series of exploratory teaching inno- vation reform are carried out，and the innovative

effect and the existing problems of pain point are summarized and analyzed. An effective way is

explored to cultivate architectural talents with solid physical skills.

In this paper，the basic equations of motion of coins under different

conditions are derived. The problem of the coin's motion around a circle is analyzed，and two

special modes of motion are discussed using the results，which are finally verified via

experiments and numerical simulations.

Based on the electromagnetic induction method，the distribution of Helmholtz coil

magnetic field under different capacitance parameters is measured by the improved method of

achieving resonance with the Helm- holtz coil in series，and the relationship between the magnetic

field of Helmholtz coil and the position of central axis is analyzed by using Origin software. The

experimental results show that the accuracy of the magnetic field of Helm- holtz coil measured by

the improved method is higher than that by the traditional electromagnetic induction method to a

certain extent. Among the three capacitor options，when the series capacitance is 0.099×10-⁶ F，the

accuracy is the highest. The fitted relationship between the magnetic field of Helmholtz coil and the

position of the central ax- is is basically consistent with the theoretical formula. The experimental effect of the improved method is obvious，the accuracy is high，and it is scientifically feasible. It is an improved method for measuring the magnetic field of Helm- holtz coils that is worth popularizing.

In this paper，the optical-fiber temperature sensor experiment is modified by using a

cheap commer- cial fiber splitter at 1310 nm and aluminum foil for thermal conducting. The

temperature coefficient is measured and found to be more stable after improvement. Also，the

conducting condition can infect the temperature coefficient a lot. At last，teaching

suggestion is proposed.

Ising model is a widely used magnetic spin interaction model. It is very complicated to

solve the ana- lytic solution in 2-D case. In practical application，Wolff algorithm is usually

used to simulate the Ising model and it is considered to be the best clustering flipping Monte

Carlo algorithm. Metropolis and Swendsen-Wang algorithms are similar to Wolff algorithm，and

theoretically they are also applicable to the simulation of Ising model. So far， there

is no paper has compared the three algorithms to show the advantages of Wolff algorithm，and there

are few in- troductions of Monte Carlo algorithm in undergraduate courses. In this paper，we use

these three algorithms to simu- late 2-D Ising model and introduce the principle，parameter

selection and implementation of the algorithms. In the end，we compare the simulation effect and

application range of the three algorithms，and summarize the reason why Wolff algorithm has better

effect in the simulation of 2D Ising model.