The only time a phone book seems useful is when looking for the number to a plumber or a Chinese restaurant. I'm sure you've never even considered how strong a phone book actually is; I know I haven't. However, after visiting Mythbusters: The Explosive Exhibition, I knew the answer to this question. It took two army tanks (8,000 pounds) to pull 2 phone books apart, and COSI has the evidence to prove it.
The remnants of 2 old LA phone books, the phone books actually used in the Mythbusters episode, sit in a cage in the exhibition. The friction between the pages of each phone book contribute to the strength and how it can stand so much weight.
The books are placed next to the phone book swing, where 4 interlaced phone books, 2 on each side, can hold you and your whole family. Go ahead, try it!
This is a part of several modules that will focus on specific aspects of the Mythbusters exhibit, including insight into the science behind several of the experiments.
Go see for yourself and sit on the phone book swing at Mythbusters: The Explosive Exhibition, now at COSI until September 2.