Resumen de Determination of the Coefficient of Thermal Expansion by Measuring Frequency of a Heated Music Wire
Robert Polak, Anthony Kearns, Kiet A. Nguyen, Michael R. Harris
Engaging with physical and material properties through empirical observation is a fundamental part of undergraduate physics and engineering education. Several works have proposed experiments to determine thermal physical constants of materials, such as finding the coefficient of linear expansion.1–4 As Dajbych5 and Polak et al.6 have shown, physical constants can be verified by measuring the frequency of a plucked high-carbon steel wire on a guitar. Building on our previous work,6,7 we have extended our method to verify the coefficient of linear thermal expansion, αT, through an accessible procedure directed at introductory physics education. To do this, we heated a guitar wire by running a current through it, causing the string to expand and resulting in a measurable decrease in frequency. Using only a DC power source, an acoustic guitar, two digital multimeters, and a cell phone, students can calculate the coefficient of thermal expansion within a typical lab duration.
