General Engineering Science In Si Units. The Commonwealth And International Library: Mechanical Engineering Division

General Engineering Science in SI Units IN TWO VOLUMES Volume 2 G.W. MARR B.Sc.(Eng.), C.Eng., M.I.E.E. Lecturer in the Engineering Department, Cambridgeshire College of Arts and Technology PERGAMON PRESS OXFORD · N E W YORK · TORONTO SYDNEY . BRAUNSCHWEIG Pergamon Press Ltd., Headington Hill Hall, Oxford Pergamon Press Inc., Maxwell House, Fairview Park, Elmsford, New York 10523 Pergamon of Canada Ltd., 207 Queen's Quay West, Toronto 1 Pergamon Press (Aust.) Pty. Ltd., 19a Boundary Street, Rushcutters Bay, N.S.W. 2011, Australia Vieweg & Sohn GmbH, Burgplatz 1, Braunschweig Copyright © 1971 G. W. Marr All Rights Reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of Pergamon Press Ltd. First edition 1963 Second edition in SI units 1971 Library of Congress Catalog Card No. 78-133401 Printed in Hungary This book is sold subject to the condition that it shall not, by way of trade, be lent, resold, hired out, or otherwise disposed of without the publisher's consent, in any form of binding or cover other than that in which it is published. 08 015807 2 (hard cover) 08 015806 4 (flexicover) List of Tables Coefficients of linear expansion Temperature coefficients of resistance Common units, symbols and abbreviations Multiples and sub-multiples Conversion factors Common logarithms Antilogarithms Trigonometric functions X 113 144 210 212 213 214 216 218 Preface book is the second of two volumes written primarily to cover the Engineering Science content of the General Course in En­ gineering. It is, however, hoped that some students may find it helpful during the earlier years of CGLI Technician Courses and other engineering courses. The content of this volume corresponds in the main to the re­ quirements of the syllabus for the second year of a two-year course. There are two exceptions to this—the sections devoted to Young's Modulus and to heat exchange in mixtures. These items were intentionally included in the first volume so as to follow other first year topics to which they are closely related. Great care has been taken to avoid errors either in the text or in the answers to exercises. Some, however, may remain and I shall be grateful to have my attention drawn to any which have been overlooked. THIS Cambridge G. W. MARR xi Use of Distinguishing Type for Symbols Geometrical points are represented by letters in Roman type, e.g. the point P. Vector quantities, when both magnitude and direction are con­ sidered, are represented by letters in bold type, e.g. force P. Scalar quantities, and vector quantities where only the magnitude is being considered, are represented by letters in italic type, e.g. the p.d. F, the weight W. Drawing Symbols Resistor - fixed resistance Rheostat - variable resistance Potential divider -^j| If- Battery of cells Indicating instrument e.g. ammeter xii Section 1 Concurrent Forces 1.1. Introduction The reader will recall that in volume 1 a distinction was drawn between quantities—such as work, area, and temperature—which could be sufficiently described by stating their magnitudes, and other quantities—such as force and displacement—which required, in addition to a statement of magnitude, an indication of direction. These kinds of quantities were termed scalar quantities and vector quantities respectively. The need for special rules which apply to the addition of vector quantities was demonstrated. In particular the use of the parallelogram and of the triangle of forces as a means of obtaining the resultan