Latent heat of fusion of ice . au of Standards, but not yet pub-lished, the authors have used the value international joulesequal to one 150 18 See footnote 10 on p. 236. 19 Some modification of the results announced in this paper will be necessary if conclusive evidence shalllater indicate a value of J different from , but it seems very improbable that such change will exceed j part in 2000. 256 Bulletin of the Bureau of Standards [Vol, xo Radiation and Convection from Jacket (2).—During the periodthat the ice was melting the temperature difference between thecalorimeter and
Latent heat of fusion of ice . au of Standards, but not yet pub-lished, the authors have used the value international joulesequal to one 150 18 See footnote 10 on p. 236. 19 Some modification of the results announced in this paper will be necessary if conclusive evidence shalllater indicate a value of J different from , but it seems very improbable that such change will exceed j part in 2000. 256 Bulletin of the Bureau of Standards [Vol, xo Radiation and Convection from Jacket (2).—During the periodthat the ice was melting the temperature difference between thecalorimeter and jacket was directly indicated by a readings every half minute (zero setting 15) show that thecalorimeter temperature dropped steadily below that of the jacket(see Fig. 9) to a point where the galvanometer deflection was , equivalent to , held steady for about a minute, and thenrecovered steadily to the jacket temperature. The averagedeviation, the time and the cooling constant20 of the calorimeter. 39 40 41 TIME IN MINUTES Fig. 9 are set forth in order, and show the method of computing thequantity of heat involved in this correction. Stirring (3).—The stirring was very constant as shown by theparabolic speed indicator mentioned before, and the power supplyof watts at the speed employed has been measured manytimes during the use of the calorimeter. This figure is equiva-lent to calories per minute. The rest of the computationon the sheet requires no further explanation. Heating of Calorimeter (8).—Any excess of energy above thatabsorbed by the ice and its holder will serve to raise the tempera-ture of the calorimeter and a deficiency will be supplied by the *> Value given on p. 242. o%kJtne°n,Harper] Latent Heat of Fusion of Ice 257 lowering of this temperature. The quantity of heat so involvedis obtained from the product of the heat capacity of the calori-meter (without the ice) by the temperature change. The heat capacity, inclu
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