Using Math in Physics: 1. Dimensional Analysis

• Edward F. Redish ^[1]
  1. [1] University of Maryland, College Park

     University of Maryland, College Park

     Estados Unidos

     
• Localización: The Physics Teacher, ISSN 0031-921X, Vol. 59, Nº. 6, 2021, págs. 397-400
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • Making meaning with math in physics requires blending physical conceptual knowledge with mathematical symbology. Students in introductory physics classes often struggle with this, but it is an essential component of learning how to think with math. Teaching the dimensionality1 of measured quantities and dimensional analysis (DA) is a valuable first step in helping them learn to appreciate this difference. In this paper I discuss some of the issues associated with learning dimensional analysis and show some ways we can modify our instruction to help. This paper is one of a series on how to help students develop the scientific thinking skills required for learning to use math in science.2 We often treat DA as if it’s just unit checks and only a way to find calculational mistakes. But dimensionality plays a more fundamental conceptual role. DA is one of the basic “e-games” (knowledge building strategies or “epistemic games”)3 that can help students learn to blend physical concepts with mathematical representations. For our pre-medical students, the AAMC, the group responsible for developing the MCAT, has identified dimensional analysis as one of the primary learning objectives in developing quantitative numeracy.4 The icon I use for the DA e-game is a measuring tape, shown at the top of the page. Every time I use DA in class, that icon appears on the slide. Every time it’s used in our text (a free web-based wiki5), the icon appears. This provides a visual marker to remind students how valuable (and common) this strategy is.