Ex) Article Title, Author, Keywords
Ex) Article Title, Author, Keywords
Abstract : This study introduces a scientific inquiry activity to analyze the magnetic braking phenomenon. This phenomenon occurs when a permanent magnet is brought close to a rotating conductive plate, resulting in a decrease in the plate’s velocity due to magnetic drag force (FD). The FD was measured using the rotated angles of a permanent magnet pendulum positioned near the conductive plate while the plate was rotating. This FD demonstrated a linear proportionality to the velocity. The coefficient α, determined by the electrical resistances inside and outside the magnetic field zone on the plate, exhibits a dependence on the magnet’s shape and is proportional to the square of distance (d) between the magnet and the plate. This proportionality arises because the area of the magnetic field (B) on the plate increases with increasing d. The area coefficient, χ, was determined by this relationship. When the circular or square magnet is positioned near the rotating conductive plate, the FD exponentially decreases the plate’s angular velocity (ω). The inverse of the time constant, 1/τ, is linearly proportional to χB2.
Abstract : Atomic force microscopy (AFM) is widely used for surface analysis due to its versatility and ability to provide 3D surface information. Especially, the quartz tuning fork (QTF)-AFM enables highly sensitive measurements with a simple electronic circuit, while scanning electron microscopy (SEM) allows rapid high-resolution imaging over large areas. To combine the strengths of these two techniques, a hybrid system integrating QTF-AFM and SEM was developed to analyze how the QTF, a key component, responds in a vacuum environment depending on the presence of the probe under vacuum and electron beam exposure. As a results, in a vacuum environment, it was observed that the QTF’s quality factor (Q) increased when transitioning from atmospheric pressure to vacuum, and the amplitude of the resonant frequency slightly decreased but stabilized over time with minimal phase change.
Abstract : The purpose of this study is to analyze the inquiry process of science-gifted students using classical methods in relation to Galileo's inclined plane experiment and to assess their perception of classical experimental methods. The gifted students designed and conducted experiments using both classical methods, simulating the 17th-century context, and modern methods, utilizing video analysis techniques. The main research findings are as follows. First, the gifted students designed and conducted experiments using the classical method with time and travel distance as the main variables, employing pendulums, water clocks, constant velocity motion devices, and hourglasses as time measurement tools. Second, despite the presence of error factors due to uncertainty in human sensory perception or the limitations of measurement tools in the classical method, the experimental results are very successful. Third, many gifted students exhibited a positive shift in their perception of classical methods after the activity. Based on the findings of this study, the potential for integrating classical methods with modern methods is discussed.
Abstract : The electromagnets used in the 4th Generation electron Storage Ring (4GSR) require a higher field gradient than the conventional magnets facilitated in a machine. However, the magnetic field at the pole-tip saturates at the level of 1.3 T, resulting in the dilution of the operational efficiency. Therefore, a higher magnetic field gradient is only feasible by reducing the diameter of the magnet. However, as the diameter of the magnet decreases, the shape of the pole determines the higher-order term strongly, so it is essential to take account into the design of the magnet. In this presentation, we present an optimization strategy of the pole shape for the occasion of magnetic saturation using a 2D solver and Pymoo optimization algorithms using the Poisson Superfish code.
Abstract : As an essential feature of doing science or physics, inquiry and laboratory work have been emphasized as both pedagogical goals and strategies. The discussion on what constitutes physics inquiry and laboratory work has philosophical, cultural and historical aspects and also reflects the relatively recent development of science curriculum. In this paper, I have reviewed how the notion of science inquiry and laboratory work has changed and elaborated on the recent emphasis on scientific practices in doing physics. The review has shown that students’ doing science or physics entails their epistemic agency while participating in scientific practices and sensemaking. Following the review, I have presented an empirical analysis of middle school science teachers’ facilitation, or lack thereof, of students’ sensemaking during scientific practices. The analysis revealed several strategies that facilitated students' sensemaking during scientific practices and underscored the critical role of teacher noticing in supporting students’ sensemaking. Further research topics are suggested in the conclusion.
Youngchun Jo, Haeyong Kang, Hyunkyung Lee, Jinho Jeon, Hyeonseop Lee, Kanghyun Kim
New Phys.: Sae Mulli 2024; 74(1): 25-34
https://doi.org/10.3938/NPSM.74.25
Sangwoo Ha
New Phys.: Sae Mulli 2023; 73(9): 734-749
https://doi.org/10.3938/NPSM.73.734
Hunkoog Jho*
New Phys.: Sae Mulli 2024; 74(8): 812-823
https://doi.org/10.3938/NPSM.74.812