The 5 Steps to a 5: AP Physics 1 book is out. You can buy here via amazon. I've completely rewritten the text from previous Physics B version because, well, the AP Physics 1 exam is completely different. Last week in Barnes and Noble, I couldn't find any other prep books for the new exam. And I don't trust the competing companies' books, anyway.*
* I suspect they're all superior to Barry Panas's "1 Step to a 1," which offers a money-back guarantee.
I really like the approach to content in this year's book. Instead of textbook-style exposition, example problems, and practice problems, each of the content chapters intertwines exposition and examples. In the spirit of the new exams, the "examples" don't pose a particular problem to solve -- getting hung up on the exact correct answer rather than the process and explanation will be a particularly harmful bugaboo on this new style of exam. Rather, the examples pose situations which are fertile ground for all sorts of kinds of problems. Then, I suggest what kinds of questions could be spawned from each situation, and I show how to answer each of these questions.
The book includes a variety of practice questions in each content chapter, and a complete practice exam written directly to the AP Physics 1 learning objectives and science practices. And already I've found the first major error... that's inevitable, of course, in a first edition. Even though I worked through everything multiple times, the first time I read the published version I found the stupidicism. In the forces chapter, I ask a question about a block pulled along the ground by a string angled up 30 degrees above the horizontal. Great... except that in the solution I state that the normal force on the block is equal to its weight. Duh. Since the string force has an upward vertical component, the normal force on the block must be LESS than the block's weight. Grrr. I'll have to rewrite that one for the second edition.
Any other comments, ideas, complaints, or suggestions can go in the comments, or can be sent to me via email. Enjoy the book
Are there plans for a 5 Steps AP Physics 2?
ReplyDeleteNot by me. McGraw-Hill has contracted with someone -- I don't know who -- to write the Physics 2 version.
ReplyDeleteI'm about to give the practice test to my class next week. It's a huge help to see questions written in the new style of the test (so many of the other prep books have AP B questions in them)
ReplyDeleteCan you clarify a couple points?
In MC 27 - is the distance supposed to be in m or cm?
in MC 42 - is option C supposed to read "which varies directly with the wavelength"?
in MC 21 - the angular speeds of the wheels will be different in relation to the velocity of the wagon due to their different radii. I think wagon A ends up with a greater rotational kinetic energy than B for the same transnational speed due to its smaller radius. Am I wrong here?
I'm about to give the practice test to my class next week. It's a huge help to see questions written in the new style of the test (so many of the other prep books have AP B questions in them)
ReplyDeleteCan you clarify a couple points?
In MC 27 - is the distance supposed to be in m or cm?
in MC 42 - is option C supposed to read "which varies directly with the wavelength"?
in MC 21 - the angular speeds of the wheels will be different in relation to the velocity of the wagon due to their different radii. I think wagon A ends up with a greater rotational kinetic energy than B for the same transnational speed due to its smaller radius. Am I wrong here?
Thank you
MC 27 -- we redid that in the 2016 edition because of the mismatched units. I forget what we did with it. For now, you can assume it's in meters, but that's physically unreasonable -- I ain't stretching a spring across a football field. :-)
ReplyDeleteMC 42: This was a typesetting or proofreading error. I think you're right about what it's supposed to read, but I don't remember exactly how it was fixed for the 2016 edition.
MC 21: Here I'm pretty sure the problem and answer as written are correct. You're right that the angular speeds of the wheels will be different... but we're considering the translational speed of the cart's center of mass. For a low-I wheel, the energy input goes more into translational KE; for a high-I wheel, the energy input goes less into translation and more into rotation. The specifics of the angular speed and its relationship to the linear speed can be worked out, but they're not important to the question as asked. Just focus on the work-energy theorem in its entirety as applied to the entire wagon.
Thanks for the prompt reply - I was similarly amused by the units on the spring problem - that would be an impressively long spring.
ReplyDeleteAs for #21, I've worked out the values a few times and keep getting the same results. Maybe it would help to be specific:
If we assume the wagon's total mass is some value, m, then its translational KE would be 50m at 10 m/s.
The rotational KE for the wheels in each case would be 4 x (1/2Iw^2).
The angular speed of the wheels when the wagon is moving at 10 m/s should be 10/r (where r is the radius of the wheels)
For wagon A that gives: 4 x (1/2 x [1/2 x 0.5 x 0.1^2] x [10/0.1]^2) = 50 J
For wagon B that gives: 4 x (1/2 x [1/2 x 0.2 x 0.2^2] x [10/0.2]^2) = 40 J
For wagon C that gives: 4 x (1/2 x [0.2 x 0.1^2] x [10/0.1]^2) = 40 J
So the total energy of the cart in each case should be as follows:
Wagon A: 50m + 50J
Wagon B: 50m + 40J
Wagon C: 50m + 40J
Since all the wagons start from rest, Wagon A must require the greatest energy input.
Where did I go wrong?
Hello! I'm currently am a high school student using your book. I have to say that this book is extremely helpful and detailed. The explanations are not absurdly difficult to understand and the tips for the actual test are very insightful. Everything is so organized and easily to learn. This book has taught me more about physics than my teacher ever will. I especially appreciate the pizza parlors and plan to go on a road trip to check them out one day. So, thank you!
ReplyDelete