IDNLearn.com offers a user-friendly platform for finding and sharing answers. Join our community to receive prompt and reliable responses to your questions from knowledgeable professionals.
Answer: Static Friction
Explanation: As you tilt the book you know that it will stay fixed to start with, but eventually, once the angle is large enough, the book will start to slide. It is the static friction force that holds the book in place at small angles of tilt.