Abstract: This work innovatively proposes the reduced stiffness coefficient method for the two-body problem involving spring interactions. By establishing equivalent parameters (reduced stiffness coefficients), this method simplifies the processing of multi-body systems and clarifies the presentation of physical processes. In terms of student competency development, the approach leverages transformation training from “complex systems” to “equivalent single bodies,” aiding students in mastering analogical thinking and problem reconstruction skills. Additionally, through formula derivation, it inspires students to grasp the thinking paradigms in scientific research and reinforces the educational value of the equivalence concept.

Key words: two-body problem, reduced mass, reduced stiffness coefficient, equivalent concept