Development of a microcontroller-based instrument for measuring liquid density

Abstract

The purpose of this research was to develop a practical tool to measure the density of liquids. This research was a research and development research that referred to the development model of Borg and Gall. The research instrument used was a questionnaire with a 4-Likert scale. Evaluation phase included the assessment of media validator, students' responses, and laboratory test. The product quality data obtained were analyzed using descriptive analysis. The quality of the product based on the analysis of the media expert's assessment obtained a value of 3.30 which was in very good category. Meanwhile, the results of student responses in the limited-testing obtained a value of 3.30 which showed that they strongly agree with the product's usability. The test results and questionnaire analysis indicated that the microcontroller-based density determination practicum tool developed was feasible to use. From the experimental results, the density value of water was 0.95 gr/cm3with a standard deviation of ±0.044 and a relative uncertainty value of 0.22%. The density value for salt water was 1.04 gr/cm3with a standard deviation of ±0.011, compared with the literature which is 1.10 gr/cm3. Moreover, the density of coconut oil measured was 0.76 gr/cm3with a standard deviation of ±0.045, while the literature is 0.84.