What If? 2: Additional Serious Scientific Answers to Absurd Hypothetical Questions is a book by Randall Munroe, the creator of the webcomic xkcd . It follows the same format as the original What If?, taking reader-submitted questions that are often strange or impractical and answering them through scientific reasoning.

The book explores a wide range of topics, from the feasibility of riding a fire pole from the moon to the consequences of opening everyone's freezer door at the same time. Munroe uses humor, clear explanations, and illustrations to make complex scientific concepts understandable to a general audience.

Here are some of the interesting questions tackled in What If? 2:

• What would happen if you tried to dig a hole straight through the Earth?
• How many people would you need to kill to noticeably cool the planet?
• What if the Earth had rings like Saturn?
• Could you survive a fall from the Empire State Building by landing in a pile of hay?