Resumen de Measuring the Expansion Coefficient of Water Using Lloyd’s Mirror

Shizhuo Luo, Zengming Zhang, Lazhen Sun, Zhongqing Wang, Minghui Ma

• The determination of the thermal volume expansion coefficient is very important in engineering technology. According to the interference principle of Lloyd’s mirror, an experimental device was designed and constructed to measure the thermal volume expansion coefficient of water with high precision. The thermal volume expansion coefficient is 7.296 × 10−5 °C−1 (the water temperature is 9 °C), and the relative error is 1.52%. The result is better than that obtained by other measurement methods. The experimental device is easy to set up and can be used as a student-directed inquiry-based learning, which strengthens students’ understanding of the principle of interference. Students can practice the construction of light paths and the acquisition, processing, and analysis of experimental data, and learn a method of measuring microdisplacement.