Excerpted from
Excerpted from Cracking the AP Physics B Exam, 2013 Edition by Steven A. Leduc & John Miller. Copyright © 2012 by The Princeton Review, Inc. Excerpted by permission of The Princeton Review imprint of the Random House Children's Group, a division of Random House, Inc. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.