A Comprehensive Analysis of the Work-Energy Theorem Across Classical, Quantum, and Relativistic Regimes
Md. Shaikhul Hadis Nazat
Abstract
Abstract The Work-Energy Theorem is a fundamental principle in mechanics, establishing a quantitative relationship between the net work done on a particle and its change in kinetic energy. In this study, we present a rigorous derivation of the theorem across classical, quantum, and relativistic frameworks. The analysis includes expressing kinetic energy in terms of de Broglie wavelength, introducing identities linking force, displacement, and wavelength, and extending the theorem to relativistic particles. We provide detailed mathematical derivations, highlight the transition between classical and quantum regimes, and discuss the limits of applicability, including decoherence effects and classical limits. This work demonstrates the universality of the Work-Energy Theorem and bridges diverse physical perspectives under a unified framework.