PHYSICS
TOWER, SMITH, TURTON,
AND
COPE
(See p.441)Three-color Printing
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PHYSICS
BY
WILLIS E. TOWER, M. SCI. (Univ. of Illinois)
HEAD OF THE DEPARTMENT OF PHYSICS, ENGLEWOOD
HIGH SCHOOL, CHICAGO
CHARLES H. SMITH, M. E. (Cornell)
HEAD OF THE DEPARTMENT OF PHYSICS AND ASSISTANT
PRINCIPAL, HYDE PARK SCHOOL, CHICAGO
CHARLES M. TURTON, A. M. (Syracuse)
HEAD OF THE DEPARTMENT OF PHYSICS, BOWEN
HIGH SCHOOL, CHICAGO
IN COLLABORATION WITH
THOMAS D. COPE, Ph.D. (Pennsylvania)
ASSISTANT PROFESSOR OF PHYSICS, UNIVERSITY
OF PENNSYLVANIA
BASED UPON
PRINCIPLES OF PHYSICS
BY
TOWER, SMITH and TURTON
WITH 7 PLATES AND 448 OTHER ILLUSTRATIONS
PHILADELPHIA
P. BLAKISTON'S SON & CO.
1012 WALNUT STREET
Copyright, 1920, by P. Blakiston's Son & Co.
PREFACE
In the preparation of this text, the pupil, his experience,needs, and interests have been constantly kept in mind.The order of topics, illustrations, and problems havebeen selected with the purpose of leading the pupil intoa clear understanding of the physical phenomena continuallytaking place about him.
The recommendations and conclusions reached by the"New Movement in the Teaching of Physics" have beenincorporated into the book as a whole. These conclusionsindicate that the most efficient teaching in physics involvesa departure from the quantitative, mathematical methodsof presentation that were in general use a dozen or moreyears ago, toward a method better adapted to the capabilities,interests, and requirements of the young people inour physics classes.
The older methods are effective with a portion of thestudent body which has the greater mathematical abilityand training, but they discourage a large majority of thepupils who are not gifted or prepared for severe mathematicalanalysis. For this reason, many of the more difficultmathematical demonstrations often given in physicstexts are omitted. Most of the problems involve only theunits employed in practical every-day measurements.
The portions of Mechanics that are ordinarily so difficultfor the average pupil are not taken up until he hascovered considerable ground with which he is more or lessfamiliar and not until he has become somewhat accustomed[Pg vi]to the methods of study and the technical terms of thesubject.
The pupil c