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arXiv · 2501.02257

Using a remote control to determine the infrared absorption coefficient in water

Santiago Ortuno-Molina·Adrian Garmendia-Martinez·Francisco M. Munoz-Perez·Juan C. Castro-Palacio·Juan A. Monsoriu
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Abstract

In this work, we present a simple and low cost experiment designed to determine the infrared water absorption coefficient. We used a TV remote control as a point source of infrared light. The intensity after passing the light through different heights of a water column is measured with a solar cell connected to a speaker. The recorded signal, captured with a smartphone sound recorder, provides a practical demonstration of the Beer Lambert law. The collected data were fitted to the theoretical model, obtaining a very good agreement between the value of the water absorption coefficient obtained experimentally and that reported in the literature.

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Santiago Ortuno-Molina, Adrian Garmendia-Martinez, Francisco M. Munoz-Perez, Juan C. Castro-Palacio, Juan A. Monsoriu. 2025-01-04. Using a remote control to determine the infrared absorption coefficient in water. https://arxiv.org/abs/2501.02257

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