Meandering Road From Dynamics To Thermodynamics And Vice Versa: What Is Work?

The science of mechanics may trace back to Aristotle (384-322 B.C.) and Archimedes (c. 287-212 B.C.), while thermal science may trace back to the steam engines by Savery in 1697 and Newcomen in 1712 or to the works of Rankine, Clausius, and Lord Kelvin in the 1850s. Both are old sciences where, from time to time, definitions formulated for terms to serve the purpose of previous existing physical understanding are later found inadequate, incorrect, or inconvenient for the description of more complete modern knowledge. Some definitions and conventions in dynamics and thermodynamics are given differently and can be confusing to unsuspecting undergraduate students who are taking them in their curricula. To a certain extent, this is the case with the terms heat, work, potential energy, and conservation of energy. This paper is aimed at pointing out the curvy and bumpy stretches on the road from dynamics to thermodynamics, and vice versa. It is hoped that better inter-disciplinary understanding will enhance effective communication for instructors and better learning for engineering students.