Recent Books by Robert Ehrlich:

What If? Mind Boggling Science Questions for Kids
Why Toast Lands Jelly-Side Down
What if You Could Unscramble an Egg
The CUPS Series: Consortium for Upper-Level Physics Software
The Cosmological Milkshake: A Semi-Serious Look at the Size of Things
Turning the World Inside Out and 174 Other Simple Physics Demonstrations

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What If?  Mind-Boggling Science Questions for Kids
John Wiley & Sons, NY 1998

Discover the amazing answers to some cool and weird questions about our world

What if the earth stopped spinning? What if we could see sounds? What if the moon fell down? What if aliens landed and only wanted to talk to dogs?  Bizarre brainteasers and ingenious inquiries set the stage for a fantastic foray into the wacky world of real science.  The intriguing topics range from plants and animals to light and sounds, from the wind and the weather to the planets and the stars.  Captivating cartoons and quick, fun-filled experiments will stretch your mind and your imagination.

Why Toast Lands Jelly-Side Down
Princeton University Press, 1997

In this sequel to “Turning the World Inside Out,”  Robert Ehrlich recognizes that physics is often perceived as being highly abstract, user-unfriendly, and remote from everyday life.  However, he has spent much of his career disproving these stereotypes.  In the latest of his provocatively titled books, he provides a collection of simple physics demonstrations and experiments that will be extraordinarily useful to teachers and extremely instructive to students.  Intentionally using “low tech” and inexpensive materials from everyday life, Why Toast Lands Jelly-Side Down humanizes key principles of physics.  As Ehrlich puts it, “I don’t argue against using complex apparatus when necessary, only avoiding it if possible.”  He ardently believes that the best demonstrations are the simplest ones.  The fact that hey also save money is an added bonus.

      The book begins with a practical introduction on how to design physics demonstrations.  The benefits of designing one’s own “demos” are numerous, but primary among them is the increased understanding of basic physics that results.  For many instructors, demonstrations seem dauntingly complex, filled with hard-to-find equipment and too many possibilities for failure.  The demonstrations presented in this book are exactly the opposite.  Ehrlich describes them with characteristic candor: “You can fit many of them in your pocket, bring them to class without any set-up required, and best of all, you need not fear that your demo will more likely illustrate Murphy’s laws rather than Newton’s”

        After laying out the basic principles of designing successful demonstrations, Ehrlich provides more than 100 examples.  Some of the more intriguing include: Estimating the Net Force on a Bent Straw; Terminal Velocity of Falling Coffee Filters; Avalanches in a Sand Pile; Spinning a Penny; Dropping Two Rolls of Toilet Paper; When to Add the Cream to Your Coffee; Swinging Your Arms While Walking; The “Tachyon Telephone”; and, of course, Why Toast Lands Jelly-Side Down.  For anyone with even the slightest interest in physics, this book is filled with learning opportunities.  For physics researchers and students, it is an essential resource.

“A charming and delightful book full of useful advice.  Anyone who teaches undergraduate physics can find something of value in it for almost any course.”
—Mark P. Silverman, Trinity College

What If You Could Unscramble an Egg?
Rutgers University Press, New Brunswick, NJ, 1996

What if there were three sexes?
What if men could have babies?
What if the earth didn't have a moon?
What if you fell into a black hole?
What if you could unscramble an egg?

These are some samples of questions considered in a free-wheeling dialog that will stretch your imagination in 102 different directions. In these flippant "what if" dialogs about everything from sex , aliens, dogs, and dinosaurs to space, time and matter, Ehrlich blurs the boundaries between science fact and fiction. Come travel through these zany alternative universes, and understand our own a bit better.

What others have said about the book:

“These clever pieces, accompanied by humorous illustrations, are clearly written and easy to understand, with a minimum of mathematics.  As enjoyable as Douglas Adams’s The Hitchhiker’s Guide to the Galaxy.” -- Library Journal.

The CUPS Series: Consortium for Upper-Level Physics Software
John Wiley & Sons, NY, 1995-1996

This series of nine volumes includes sophisticated animated simulations useful as lecture demonstrations and homework exercises for nine of the courses in the junior/senior undergraduate curriculum: astrophysics, solid state (condensed matter) physics, electricity & magnetism, classical mechanics, modern physics, nuclear & particle physics, quantum mechanics, thermal & statistical physics, waves & optics.  Developed by an international team of 27 physicists, and led by Ehrlich and his colleagues Maria Dworzecka and William MacDonald, CUPS programs have won a number of awards for physics instructional software.

The Cosmological Milkshake: A Semi-Serious Look at the Size of Things
Rutgers University Press, New Brunswick, NJ, 1994

From the zany—

How long a hot dog would you be?  How much hotter is the bottom of a waterfall than the top?  When should you add cream to your coffee?  One how big a planet could you hit a baseball into orbit?

To the serious—

How close could you get to Ground Zero and survive?  How long has it been since the last mass extinction?  How old is life on earth?  How big is the universe.

What others have said about the book:

“Ehrlich manages to convey painlessly and awful lot of science . . .would make a great gift for a child showing worrying signs of wanting to think like a scientist.     --New Scientist

"These bite-sized essays and cartoons entertain while they educate you about the sizes of stuff in the universe.  If you ever wondered how fast you’d have to jump to survive in a falling elevator.  The Cosmological Milkshake is the book for you. " -James T. Trefil, author of A Scientist in the City

Turning the World Inside Out and 174 Other Simple Physics Demonstrations
Princeton University Press, 1990

“. . . dipping into this collection is much like opening a holiday gift and discovering a marvelous little toy that then holds your attention by some curious performance . . . .This book precisely reflects the way science education should be, especially at the introductory level.”

--From the Foreword by Jearl Walker

Here is a collection of physics demonstrations costing very little to produce yet illustrating key concepts in amazingly simple and playful ways.  Intended for instructors, students, and curious lay readers, these demonstrations make use of easily accessible, everyday items: food coloring and glycerine swirled and then “unmixed” in a container demonstrate aspects of the entropy law; raw eggs thrown with full force at a sheet but not breaking illustrate Newton’s second law (f=ma); and the reflection off a glass Christmas tree ball is the focus of an explanation on “turning the world inside out.”  Many of the demonstration are either new or include innovative twists on old ideas, as in the author’s simplified version of the classic “Monkey and hunter” problem, which substitutes “diluted gravity” on an inclined plane for large apparatus.

        Each demonstration outlines the objective, the equipment needed, and the procedure, including, in many instances, ways for a teacher to perform the demonstration on an overhead projector.  Throughout the book concrete examples are accompanied by enough theoretical background to enhance a reader’s basic understanding of physical principles.  Lab instructors will find that demonstrations containing a quantitative component work well as mini-experiments and as ways to illustrate the results of calculations.  These diverse and flexible demonstrations will serve a wide range of educational levels, from middle school physical science to university physics.