シャルルの法則を学ぶ授業事例 : 空気温度計の作製から絶対零度の算出までを通して

抄録

In this paper we report a case study conducted at a public high school in Nagano Prefecture, in which our proposed unit program of three class hours was carried out to help students to understand Charles's law using an air thermometer. Several experiments on Charles's law have been reported, but they are not suited for experimental study by individuals and do not apply to multi-purposed studies. The principle to measure temperature by an air thermometer developed by us is based on Charles's law. In this case study, each student made his own thermometer, made a graph by plotting the water heights of the air thermometer versus temperatures to confirm Charles's law, extrapolated the line of each graph and also calculated the plotted data to determine the absolute zero point. Students enhanced their learning motivation and understood Charles's law. The extrapolated value (-274±22℃, n=42) determined by the students approximated the absolute zero point (-273℃). A similar value (-276±23℃, n=42) was also obtained by calculation of the plotted data. Our experiment using the air thermometer is found to be superior to the ones reported in obtaining the absolute zero point. Some students were surprised at now easy the experiment to determine the absolute zero was, point and they also changed their scientific perception during the unit program. Most students were satisfied with their achievements. It is thus suggested that our unit program using the air thermometer is useful for students not only to understand Charles's law and to determine the absolute zero point, but also to change their scientific perception as to be satisfied with their achievements through individual experimental study.