Abstract
This article provides a detailed explanation of Albert Einstein's famous mass-energy equivalence principle, focusing on a modern interpretation that distinguishes between rest mass and total energy. It clarifies the common misconception that a moving object's mass increases as it approaches the speed of light. Instead, the paper explains that an object's rest mass (m_0) remains constant, while its total energy (E) increases significantly. The article derives the key relativistic energy equations, including the relationship between rest energy (E₀) and Kinetic energy (E_k), thereby offering a precise and up-to-date understanding of these fundamental physical concepts.
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