# ‘What-if?’ gives you all the science answers

May 23, 2016

HOUGHTON MIFFLIN HARCOURT

BY MATTHEW BISCHOFF
SNN Staff Writer

Have you ever wondered what would happen if you tried to hit a baseball at 90 percent the speed of light? Have you ever wondered what would happen if you gathered a mole of moles in one place? What If?, published in 2014, offers a unique take on questions people ponder in their everyday lives.

The author, Randall Munroe, graduated from Christopher Newport University with a degree in physics. He then worked on robots for NASA. Next, he decided to write comics full time on his blog xkcd.com. He released What If? as a collection of a lot of the blog’s most popular answers to posted questions.

When I first started to read the book, it was mainly out of curiosity. I wanted to know some of the answers to the crazy proposed questions. As I got further into the book, I really began to enjoy Munroe’s writing style and his sometimes extreme speculation about what would happen after the immediate effect of various proposed questions. At one point he even uses giraffes as units of measurement.

One peculiar entry’s answer that surprised me was “What if I took a swim in a typical spent nuclear fuel pool? Would I need to dive to actually experience a fatal amount of radiation? How long could I stay safely at the surface?” Munroe began his answer by explaining that, if you were a good swimmer, you could swim for somewhere between 10 and 40 hours. Then you would drown. This would be the same for someone swimming anywhere. He further explains that every seven centimeters of water cuts radiation in half, resulting in a relatively safe upper layer to the swimming pool. The question was a departure from the typical end-of-the-world and death-filled scenarios following most of the questions.

While not an entirely surprising answer, the solution to “Is it possible to build a jetpack using downward-firing machine guns?” was an interesting one. The short answer is yes. Munroe starts with an AK-47 or Kalashnikov, which has enough thrust to lift no more than a squirrel. He later transitions to the Gryazev-Shipunov GSh-6-30 with a thrust-to-weight ratio of 40. This is plenty enough to fly.

Overall, this is an excellent book that I highly recommend anyone read. Even if you don’t want to read the book, the illustrations associated with every answer are interesting enough.

The book was published by Houghton Mifflin Harcourt and has 320 pages. The paperback version of the book costs \$2.98 from Amazon. The hardcover version of the book costs \$14.40.