Richard P. Feynman - Feynmans Tips on Physics: Reflections, Advise, Insights, Practice, A Problem-Solving Supplement to the Feynman Lectures on Physics

ALSO BY RICHARD P. FEYNMAN

The Feynman Lectures on Physics
(with Robert B. Leighton and Matthew Sands)

Exercises for The Feynman Lectures on Physics
(with Robert B. Leighton, Matthew Sands and Rochus Vogt;
edited by Michael A. Gottlieb and Rudolph Pfeiffer)

Six Easy Pieces: Essentials of Physics
Explained by its Most Brilliant Teacher
(Six lectures from The Feynman Lectures on Physics)

Six Not-So-Easy Pieces:
Einsteins Relativity, Symmetry, and Space-Time
(Six additional lectures from The Feynman Lectures on Physics)

The Character of Physical Law

QED: The Strange Theory of Light and Matter

Elementary Particles and the Laws of Physics
(with Steven Weinberg)

Feynman Lectures on Computation
(edited by Anthony J. G. Hey and Robin Allen)

The Meaning of It All: Thoughts of a Citizen-Scientist

The Pleasure of Finding Things Out:
The Best Short Works of Richard P. Feynman

Perfectly Reasonable Deviations from the Beaten Track:
The Letters of Richard P. Feynman
(edited by Michelle Feynman)

Surely Youre Joking, Mr. Feynman!
Adventures of a Curious Character
(with Ralph Leighton)

What Do You Care What Other People Think?
Further Adventures of a Curious Character
(with Ralph Leighton)

Classic Feynman:
All the Adventures of a Curious Character
(The two previous books combined, edited by Ralph Leighton)

REFLECTIONS ADVICE INSIGHTS PRACTICE

A problem-solving supplement to

The Feynman Lectures on Physics

Richard P. Feynman

Michael A. Gottlieb

Ralph Leighton

With a memoir by

Matthew Sands

BASIC BOOKS

A MEMBER OF THE PERSEUS BOOKS GROUP
New York

Copyright 2013 by Carl Feynman, Michelle Feynman, Michael A. Gottlieb,

Ralph Leighton

Published by Basic Books,

A Member of the Perseus Books Group

All rights reserved. No part of this book may be reproduced in any manner whatsoever without written permission except in the case of brief quotations embodied in critical articles and reviews. For information, address Basic Books, 250 West 57th Street, 15th Floor, New York, NY, 10107.

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A CIP catalog record for this book is available from the Library of Congress.

LCCN: 2011944291

ISBN: 978-0-465-02921-1 (e-book)

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In the six years since the initial publication of Feynmans Tips on Physics (Addison-Wesley, 2006) interest in this supplement to The Feynman Lectures on Physics has continued unabated, as evidenced by the ever-increasing number of visitors to The Feynman Lectures Website (www.feynmanlectures.info), created in conjunction with this project: thousands of inquiries have come in, many of them reporting suspected errata in The Feynman Lectures, and many with questions and comments about physics exercises.

It is thus with great pleasure and pride we present this second edition of Feynmans Tips on Physics, published by Basic Books as part of a unification of print, audio, and photo rights pertaining to The Feynman Lectures on Physicsrights which had been assigned over the years to different publishers. To celebrate this fortuitous occasion, The Feynman Lectures on Physics (New Millennium Edition) is now being printed for the first time from a LaTeX manuscript, thus enabling errata to be corrected much more quickly, and electronic editions of The Lectures to be produced soon. In addition, this new edition of Feynmans Tips on Physics is being made available in softcover at a greatly reduced price from the hardcover original, and expanded to include three insightful interviews about The Lectures:

with Richard Feynman, in 1966, soon after his key part in the project was finished,

with Robert Leighton, in 1986, about Feynmans gifts as a lecturerand the challenges of translating from Feynmanese into English, and

with Rochus Vogt, in 2009, about the community of professors that cooperatively taught The Feynman Lectures course at Caltech.

To all of you who e-mailed or posted questions and comments about The Feynman Lectures on Physics and Feynmans Tips on Physics, we wish to offer our heartfelt thanks; your contributions and support have helped greatly to improve these books, and will be appreciated by future generations of readers. To those who wrote requesting more exercises, we apologize that they could not be included in this edition. However, your encouragement has inspired the creation of a new, expansive (soon-to-be-published) book, Exercises for The Feynman Lectures on Physics.

Michael A. Gottlieb
Ralph Leighton
November 2012

At a lonely border post high on the Himalayan frontier, Ramaswamy Balasubramanian peered through his binoculars at the Peoples Liberation Army soldiers stationed in Tibetwho were peering through their scopes back at him. Tensions between India and China had been high for several years since 1962, when the two countries traded shots across their disputed border. The PLA soldiers, knowing they were being watched, taunted Balasubramanian and his fellow Indian soldiers by shaking, defiantly, high in the air, their pocket-sized, bright-red copies of Quotations from Chairman Maobetter known in the West as Maos Little Red Book.

Balasubramanian, then a conscript studying physics in his spare time, soon grew tired of these taunts. So one day, he came to his observation post prepared with a suitable rejoinder. As soon as the PLA soldiers started waving Maos Little Red Book in the air again, he and two fellow Indian soldiers picked up and held aloft the three big, bright-red volumes of The Feynman Lectures on Physics.

One day I received a letter from Mr. Balasubramanian. His was among hundreds of letters I have received over the years that describe the lasting impact Richard Feynman has had on peoples lives. After recounting the red-books incident on the Sino-Indian frontier, he wrote: Now, twenty years later, whose red books are still being read?

Indeed. Today, more than forty years after they were delivered, The Feynman Lectures on Physics are still being readand still inspireeven in Tibet, I suspect.

A special case in point: several years ago I met Michael Gottlieb at a party where the host was displaying on a computer screen the harmonic overtones of a live Tuvan throat-singerthe kind of event that makes living in San Francisco such fun. Gottlieb had studied math and was very interested in physics, so I suggested he read The Feynman Lectures on Physicsand about a year later, he devoted six months of his life to reading The Lectures very carefully from beginning to end. As Gottlieb describes in his introduction, this led, eventually, to the book you are reading now, as well as to a new, Definitive Edition of The Feynman Lectures on Physics.

Thus I am pleased that people interested in physics all over the world can now study, with the addition of this supplemental volume, a more correct and complete edition of