著者

矢ヶ崎 克馬 幾島 康夫 照屋 全次 当山 忠久 Yagasaki Katsuma Ikushima Yasuo Teruya Zenji Toyama Tadahisa

出版者

琉球大学理学部

雑誌

琉球大学理学部紀要 = Bulletin of the College of Science. University of the Ryukyus (ISSN:02869640)

巻号頁・発行日

no.36, pp.15-23, 1983-09

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The Planck's constant has been measured in the practical training of the special course of physics with an equipment using white light with color filters, but, according to the instruction, the results obtained were very poor. In this investigation, the critical photo-current coinside with the critical wave length of the color filter is determined reasonably by knowing the wave length dependences of the intensity of radiation of the white light source and the sensitivity of electron emission of the phototube and the decreasing of the reaching ratio of photo-electrons with higher energy than that of the inverse field from the photo - electric surface to the anode. The logarithmic method is the most suitable for determination of the critical photo-current. The values obtained with this method are within 3% of error compared with the accurate value. At the same time, the differential method and that using the line spectrum source are performed with a fair accuracy.

著者

仲間 隆男 大吉 隆文 辺土 正人 玉城 純孝 内間 清晴 Burkov A.T. 矢ヶ崎 克馬 Nakama Takao Oyoshi Takafumi Hedo Masato Tamashiro Junko Uchima Kiyoharu Burkov Alxander T. Yagasaki Katsuma

出版者

琉球大学理学部

雑誌

琉球大学理学部紀要 (ISSN:02869640)

巻号頁・発行日

no.66, pp.11-20, 1998-09

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The experimental set-up for simultaneous measurements of electrical resistivity and thermopower in the temperature range between room temperature and 1300 K was developed. The mechanical contacts of thermocouples, current leads and potential probes with sample were Utilized make it possible to measure a large variety of materials and result in a flexibility with respect to the sample form and dimension. The resistivity and thermopower of pure Ni, CeB_6 heavy fermion compound and a Cr-Si thin film composite are presented as test material to demonstrate the possibilities and accuracy of our experimental set-up.