The paper presents a device that measures the surface tension coefficient of bubble solution and the viscosity coefficient of air using the dynamic bubble method. The device captures the changes in radius and the difference in internal and external pressures during the inflation process of soap bubbles, determining the surface tension coefficient of the bubble solution through data fitting. It employs the Laplace equation and Poiseuille equation to make reasonable predictions about the changes in radius during bubble contraction. The viscosity coefficient of air can be analyzed from the data of the bubble contraction process. The device integrates the measurement of liquid surface tension coefficient and air viscosity coefficient, which can enrich and enhance students' knowledge and experimental skills. The device is also adjustable for exploration and expansion, making it suitable for college physics experiment teaching.

The International Young Physicists' Tournament, the localized China Undergraduate Physics Tournament, the China Young Physicists' Tournament and a series of physics academic competitions in universities in various regions are playing an increasingly important role in basic physics teaching. Based on CiteSpace visualization software, this paper analyzes the literatures extracted from CNKI Chinese database, WOS database and Scoups database with the theme of PT series physics academic competitions, and displays the chronological distribution, the co-occurrence map of keyword, time zone map, salient words and the co-occurrence map of institution of the literatures in the form of econometric analysis and knowledge map. Combined with the development and modernization of contemporary sports events, the application of mapping knowledge in reflecting the situation of sports events, physical problem research and case analysis and basic physics experiment teaching is explored.

In this paper, the smart phone was used to study the acoustic frequency and resonance mode of coin bouncing in home environment. Firstly, according to the vibration equation of the circular plate, the expression of the natural vibration frequency of the coin is given. Then combined with specific boundary conditions, the natural vibration modes and corresponding frequencies of three types of coins are analyzed by finite element method. In the experiment, the acoustic frequency produced by the free vibration of different coins is measured by smart phone, and compared with the simulation results, then a reasonable error analysis is given. This home experiment scheme is rich in physical principles, simple and interesting, and easy to be popularized in basic physics experiment teaching.

In this paper, a home-built fluorescence microscopic spectral imaging system is introduced. The system has stable performance and diverse functions, and realizes the combination of spatial microscopic resolution and spectral detection. It has the functions of white light illumination imaging, laser excitation fluorescence imaging, microscopic spectral imaging, fluorescence spectrum detection, strain control and so on. The experimental results show that the optical resolution of the setup is 385nm, and the spectral resolution is less than 1nm. It can complete the fluorescence spectrum detection, white light illumination imaging and microscopic spectral imaging of quantum dots and monolayer two-dimensional materials. The abundant and multi-leveled experiment content based on the system can meet the learning needs of different students and provide helpful ideas for fluorescence spectrum related physics experiment teaching.

At present, the basic physics experiment teaching in nonlaboratory environment is not only a measure to deal with public security emergencies, but also changes the mode of physics teaching. Based on the case of home physics experiment teaching in Nankai University, two experimental schemes for measuring liquid surface tension coefficient at low cost in nonlaboratory environment are given. The scheme puts forward that the devices for measuring liquid surface tension coefficient by Drop weight method and Pendant drop method can be assembled by using mobile phone, simple infusion bottle and automatic pencil head. The device is used to measure the surface tension coefficient of tap water. The detailed experimental design, measurement scheme and the accuracy of measurement results are given. Its applicability in basic physics experiment teaching is also discussed.

As an important branch of dynamical systems theory, the intersection of chaos science is becoming more and more important in the fields of physics, information, finance, artificial intelligence and so on. Based on the preliminary work of the laboratory self-assembled multi-parameter chaotic pendulum experimental device, this paper firstly simulates the bifurcation diagrams from the dynamical equations with the change of driving force frequency, length of the driving arm, rotational inertia and damping term, and explores the multiplicative cycle path of the motion system to chaos. Then we investigate the effects of rotational inertia and damping term on the motion of the system by experiments. Both experimental and simulation results show that the motion state of the pendulum changes repeatedly between chaotic and periodic motion with the change of above experimental parameters, and this change is abrupt. The phase diagrams were drawn through videotaping and mass-tracking, and numerical simulation results of the dynamical equations were compared with the experimental data. This device can be used as an introduction for undergraduate students to understand complex systems.

Chaos is the classic behavior of nonlinear system, and its related research is still in the forefront. In this paper, a self-organizing chaotic pendulum driven by external force with variable parameters is designed and implemented. We set up the simplified dynamic equation of the experimental device, change the experimental parameters in the experiment, process the experimental data and draw the phase diagram by the method of image recognition, and finally compare the numerical simulation results of the dynamic equation with the actual experimental data to verify the reliability of the device. Besides, in this process, the chaos phenomenon is further explored and analyzed. The device provides a low-cost intuitive research method of chaos phenomenon, which can be used as the practice content of nonlinear physics or computational physics course for undergraduates, and deepen students' understanding and understanding of chaos phenomenon and principle.