Early on in my ambitious project, one of my Friendly Mathematicians gave me a set of college physics books from his own earlier days. At that time, I lacked most of what I needed to work with the books. But now that I have studied intermediate algebra, trigonometry and a little bit of calculus, I can apply my knowledge and work with these books. The one I am using now is a tome from 1952 (before I was born) called COLLEGE PHYSICS: Mechanics, Heat, and Sound, by Francis Weston Sears and Mark W. Zemansky. This was the second edition. The seventh edition was published in 1991 and is available for the whopping price of about $144.

Classical mechanics, which is what I am learning, hasn't changed since 1952, so I don't have to worry about the updated edition. This antique physics book is certainly good enough for what I need. I am working through the chapter on vectors, which is more complete than the Barron's book. It contains exciting (at least to me) problems involving not just two vectors, but three or four, which are resolved by finding their vertical and horizontal components and their resultants, and then re-vectoring those. In the Real World multiple vector situations occur all the time, including those inclined plane problems which I have been dealing with. There are some of them in this book.

Sears and Zemansky 1952 does not have the same undertone of Cold War paranoia that my 1958 college algebra textbook did. You'd think that it would, since 1952 was at the height of the McCarthy era and the early proliferation of nuclear weapons. But this physics text is as dry as it gets, colorless, compact, and grey, with purely abstract physics illustrated by purely abstract texts. This is the stereotype of science I grew up with: the impersonal, objective man thinking impersonal, abstract thoughts. There is one moment of zany humor, though, slipped into a problem set about gravity and acceleration on page 63:

"4-13. A student determined to test the law of gravity for himself walks off a skyscraper 900 ft. high, stop-watch in hand, and starts his free fall (zero initial velocity). Five seconds later, Superman arrives at the scene and dives off the roof to save the student…."

The problem assumes that Superman is subject to the same forces that a normal object with mass would encounter. But comic book fans (I am one, despite my inappropriate age) are still debating whether he is at all subject to the law of gravity when he flies, or whether he can stop and hover in mid-air. And what enables him to fly in the first place? Now whoever finds that out, will have done some world-shaking physics.

Meanwhile, a correction to my entry of February 27. I wrote that the sine of the angle of incidence would give the "normal" force perpendicular to the incline. That should be the cosine of the angle of incidence. The sine will give you the magnitude of the force parallel to the inclined plane. Please excuse, this is new material for me.

Posted at 3:29 am | link