Hooked on Science: Phone book friction

Did you know your phone book has muscles? Using phone books you can prove two phone books are stronger than one.

Materials

* 2 large phone books

Instructions

STEP 1: Overlap the pages of each phone book. For example, page one of the first phone book should overlap page one of the second phone book.

STEP 2: Have one person grasp the spine of one of the phone books, while another person grasps the spine of the other phone book.

STEP 3: Attempt to separate the phone books by pulling.

Explanation

Because of friction, it is difficult to separate the phone books. Friction is the resistance between two objects. By overlapping all the pages in each phone book, you created a lot of friction, which made it very difficult to separate the phone books.

Jason Lindsey is a science outreach educator with Hooked on Science. Check out his website hookedonscience.org for webcasts and experiments.