E-Book Content
PROBLEMS IN UNDERGRADUATE PHYSICS VOLUME IV MOLECULAR PHYSICS, THERMODYNAMICS, ATOMIC AND NUCLEAR PHYSICS BY V. L.GINZBURG, L. M. LE VII M. S. RABINOVICH, D.V. SIVUKHIN TRANSLATED BY D. E. BROWN TRANSLATION EDITED BY D. TER HAAR PERGAMON PRESS OXFORD • LONDON • EDINBURGH • NEW YORK PARIS • FRANKFURT Pergamon Press Ltd., Headington Hill Hall, Oxford 4 & 5 Fitzroy Square, London W. 1 Pergamon Press (Scotland) Ltd., 2 & 3 Teviot Place, Edinburgh 1 Pergamon Press Inc., 122 East 55th St., New York 22, N.Y. Pergamon Press GmbH, Kaiserstrasse 75, Frankfurt-am-Main Copyright O 1965 Pergamon Press Ltd. First edition 1965 Library of Congress Catalog Card No. 65-25 443 This translation has been made from the Russian book C~orHIk sap~aq no o6n;emy kypcy c n "irn, *gacrb II (revised edition) published by Fizmatgiz, Moscow, 1960, and includes amendments and additions supplied by the authors during the course of the translation. 2083 PREFACE THIS set of four books of problems is based on a translation of a Russian collection which has been in use by students in physics at Moscow State University and the Moscow Physico-Technical Institute for a number of years. Where appropriate, answers and solutions to the problems are given in the second part of each volume. During the course of the translation of these volumes, the authors provided a large list of amendments and additions to their Russian text and these have all been incorporated in this English edition. Many of the additional problems are on topics which have developed during recent years. The standard of the problems is roughly equivalent to an undergraduate degree course in physics at a British university, or at an American university; it varies from the simple to the rather sophisticated. They can be used in conjunction with almost any textbook on physics at the appropriate level. D. TER HAAR 111 CHAPTER I MOLECULAR PHYSICS AND THERMODYNAMICS § 1. THERMOMETRY. CALORIMETRY THERMAL EXPANSION 1. A box containing thermometers of the Florentine Academy (1660) with 50° scales was found by chance in Florence in 1829. It was found that 50° Florence (Fl) corresponded to 44° R and 0°Fl = —15°R. Find an expression for converting degrees of the Florentine scale to degrees centigrade (°C). 2. I. N. Delil', a member of the St. Petersburg Academy of Sciences, described his thermometer scale in 1733. He used mercury as his thermometric substance and took as his zero the temperature of boiling water. He divided the volume of the mercury at this point into 100,000 parts (major thermometer) and into 10,000 parts (minor thermometer) and marked off corresponding divisions on a scale; it turned out that the mercury of the minor thermometer dropped to the 150th division in melting ice. Find the expression for converting degrees Delil' (minor thermometer) to degrees centigrade. 3. Academician I. Braun of the St. Petersburg Academy of Sciences was the first to succeed in freezing mercury, in the frost out of doors on 25 Dec., 1759, at 199° D (i.e. on Delil's scale, see the previous problem). Regarding this, B.N. Menshutkin wrote in his book M.V. Lomonosov: "A mercury thermometer buried in a refrigerating mixture was broken open, and Braun obtained for the first time a ball of solid mercury. It proved to be soft, like lead, and resembled polished silver. The experiments were continued on 26 Dec., now with Lomonosov; the frost was increasing, and 212°D was reached at 3 4 MOLECULAR PHYSICS AND THERMODYNAMICS 10 a.m. on the 26th. A mercury thermometer was placed in a refrigerating mixture of snow, aqua fortis (nitric acid) and vitriol (sulphuric acid). Lomonosov described the further course of the experiments as follows: `Being in no doubt that it had already frozen, I presently struck the