pISSN 0374-4914 eISSN 2289-0041

## Research Paper

New Phys.: Sae Mulli 2019; 69: 905-915

Published online September 30, 2019 https://doi.org/10.3938/NPSM.69.905

## Definition and Explanation of Core Concepts of Thermodynamics in Physics Textbooks according to the 2015 Revised Science Curriculum

Bongwoo LEE1, Heekyong KIM2*

1Department of Science Education, Dankook University, Gyeonggi 16890, Korea

2Division of Science Education, Kangwon National University, Chuncheon 24341, Korea

Correspondence to:heekyong@kangwon.ac.kr

Received: June 25, 2019; Revised: August 7, 2019; Accepted: August 27, 2019

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

### Abstract

The purpose of this study is to identify the characteristics of the thermodynamic concepts presented in the physics textbooks according to the 2015 revised science curriculum and to draw implications for physics teaching. For this purpose, we analyzed the thermodynamic contents related to the laws of thermodynamics in 13 kinds of physics textbooks in terms of the types of definitions and the explanations of related terms. The results of this study are as follows: First, ‘internal energy’, ‘first law of thermodynamics’, and ‘thermal efficiency’, which are content elements of the curriculum, were defined in all textbooks, but other terms were used without definition in some textbooks. Second, many terms were differently defined or had mixed definitions. Third, the results that the first law of thermodynamics was expressed as $Q = \Delta U + W$ and the second law of thermodynamics was presented as the Calvin-Planck statement showed that the thermodynamics contents were described mainly by using the heat engine.

Keywords: Laws of thermodynamics, Heat, Entropy, 2015 revised science curriculum, Physics textbook