Seismic metamaterials have gained significant attention for their ability to reduce seismic wave energy. However, numerical simulations have dominated the majority of research on seismic metamaterials, with relatively few field experiments validating their effectiveness. Additionally, the focus has primarily been on attenuating Rayleigh waves, with less attention given to Love waves. In this study, we first designed a seismic metamaterial featuring a periodic and symmetric array of square holes using numerical simulations as our research platform. We then explored its attenuation effects on Rayleigh waves, particularly Love waves, through field experiments. The results revealed not only differences in energy attenuation between these wave types but, more importantly, uncovered a phenomenon that we termed Bandgap-Induced Attenuation Mode Inversion within the ultra-broadband gap that was generated by the seismic metamaterials, where Love waves exhibited greater attenuation than Rayleigh waves below 50 Hz, while Rayleigh waves exhibited greater attenuation above 50 Hz. These findings highlight the necessity of considering both wave types when designing cost-effective seismic metamaterials, providing valuable insights for the development and application of metamaterials that can effectively mitigate the energy of different seismic wave modes.

The rapid advancement of large language models (LLMs) offers transformative potential for secondary physics education. However, theoretical and practical frameworks for responsible, pedagogically sound LLM integration remain underdeveloped. This paper proposes a structured, theory-grounded framework for embedding LLMs into secondary physics instruction, informed by constructivism, cognitive load theory, and the TPACK model. We identify three core application modalities: teacher-facing instructional design tools, guarded student-facing inquiry tools, and assessment-augmentation tools. We analyze domain-specific opportunities (targeting misconceptions in mechanics and electromagnetism) and risks (cognitive offloading, epistemic opacity, algorithmic bias). Drawing on empirical evidence from a small-scale single-class pilot feasibility study rather than systematic full empirical verification , we formalize six pedagogical principles: progressive autonomy, epistemic transparency, cognitive load optimization, disciplinary fidelity, ethical scaffolding, and human–AI complementarity. A one-group pretest–posttest pilot exploration was implemented with 36 secondary school students (ages 14–16) learning Newton’s Third Law solely to examine the preliminary practicability of the proposed framework instead of validating its universal effectiveness. Data analyses included paired-samples t-tests, effect size calculation, compliance coding, and descriptive survey statistics. Results showed significantly improved conceptual understanding within this limited pilot sample ( p < 0.001, d = 1.32, large effect), high in-class observed adherence to AI use guardrails (91.7%), and generally positive learner perceptions among the participating cohort. This pilot-tested operable framework clarifies the evolving role of physics teachers as orchestrators of human–AI collaboration and offers actionable preliminary guidance for educators, instructional designers, and policymakers.

The external perturbation applied to a silo and the placement of an immobile obstacle before an exit are two common and effective ways to diminish clogging in the hopper/silo flow. Here, we incorporate the local perturbation into a fixed obstacle, and experimentally explore the effects of a rotary obstacle on clogging and the flowing characteristics in the horizontal silo flow driven by a conveyor belt. Even with a low spin rate, the total blocking probability that a particle constructs a stable blocking arch with its neighbors significantly drops. Correspondingly, the average flow rate of the particles through the exit abruptly rises, at least 1 order of magnitude better than that with an immobile obstacle and approaching the flow rate of continuous flow. The rotation enhances the breakage of clogging arches, which is responsible for improving the flowability in the horizontal silo. In addition, there always exists an optimal obstacle position at which the total blocking probability is minimal and the average flow rate peaks, regardless of the spin rate. Finally, clogging is relieved with the increase of the driving velocity of the conveyor belt, showing a “fast is fast” effect that is opposite to the “fast is slow” effect in other systems such as crowd evacuation and gravity-driven hoppers.

Seismic metamaterials (SMs) have gained significant attention for their ability to reduce seismic wave energy. However, the majority of research on SMs has been dominated by numerical simulations, with relatively few field experiments validating their effectiveness. Additionally, the focus has been primarily on attenuating Rayleigh waves, with less attention given to Love waves. In this study, We first designed a seismic metamaterial featuring a periodic and symmetric array of square holes using numerical simulations as our research platform. We then explored its attenuation effects on Rayleigh waves, particularly Love waves, through field experiments. The results revealed not only differences in energy attenuation between these wave types but, more importantly, uncovered a phenomenon we termed Bandgap-Induced Attenuation Mode Inversion within the ultra-broadband gap generated by SMs, where Love waves exhibited greater attenuation than Rayleigh waves below 50 Hz, while Rayleigh waves exhibited greater attenuation above 50 Hz. These findings highlight the necessity of considering both wave types when designing cost-effective seismic metamaterials, providing valuable insights for the development and application of metamaterials that can effectively mitigate the energy of different seismic wave modes.

RLC circuit is an important part of college physics and circuit analysis, and it is also a basic unit of electronic instruments and communication equipment, When the RLC circuit is working, the voltage at both ends of the capacitor will be overcharged beyond the supply voltage. However, existing textbooks lack necessary theoretical explanations for this phenomenon, In fact, the phenomenon of overcharging contains rich physical images. On the basis of experimental observation and analysis of the physical quantity dependence of various components in the transient process, this article conducts quantitative research from both micro and macro perspectives, explaining that the overcharging phenomenon is caused by the presence of inductance, which affects the current change mode. When the capacitor voltage reaches thepower supply voltage, the current does not reach zero, while the charging process continues,leading to the overcharging phenomenon of the capacitor voltage. The results of this paper arehelpful for students to understand the transient process of RLC circuit more deeply.

A topic of 2022 IYPT “Balls on an Elastic Band” is studied. Under the condition of linear assumption of torsion force and damping of rubber band, a two-degree of freedom linear damping free torsional vibration model is established to describe the motion law of elastic band with double ball. A shear deformation mechanical model of elastic circular axis is established to describe the mechanical properties of elastic band, and the analytical solution is given. The pendulum behavior of the double ball rubber band system is explained, and the dependence between the behavior and the related parameters is explored quantitatively. The Tracker software was used to obtain relevant experimental data to verify the correctness of the model. The constant period breaking phenomenon in the experiment was explained semi-quantitatively, and the change of the nonlinear revolution radius r with time t was analyzed qualitatively.