What If? 2: Additional Serious Scientific Answers to Absurd Hypothetical Questions

Question: “If I pulled out my eyeball and aimed it so that it was looking into my other eyeball, what would I see (assuming the nerves and veins remain undamaged)?” (241).

You would see an eyeball, surrounded by double vision as the different views from each eye overlapped. There’s no need to remove an eyeball, however, since you can experience a similar effect by looking in angled mirrors.

Question: “If ALL of Japan’s islands disappear, would it affect Earth’s natural phenomena (plates, oceans, hurricanes, climate, and so on)?” (244).

The portion of Japan above sea level weighs approximately 440 trillion tons. If it disappeared, Earth’s center of mass and its axis of rotation would shift by a foot and a half toward Uruguay, on the opposite side of the world. The change in gravity would lower the sea level in East Asia by one to two feet and raise it around South America by the same amount.

Ninety percent of Japan’s mass is below sea level. If that too disappeared, then the shift in Earth’s mass and axis would be 10 times greater. The sloshing of the sea filling in the cavity would create devastating tsunamis across the globe, and sea levels would both drop and redistribute. At present, the East China Sea is relatively isolated, but without Japan it would mix with the Pacific Ocean, changing the currents and likely affecting the region’s climate.

Question: “Can you use a magnifying glass and the moonlight to light a fire?” (249).

No, because you cannot use lenses to make something hotter than the surface of the light source itself, and the surface of the moon is cool. This can be proved through the rules of optics and thermodynamics. Passive optical systems follow the law of “conservation of etendue,” meaning that if beams of light are concentrated closer together, then they become less parallel and thus can’t be aimed at a single spot. The process of focusing through a lens must also be reversable, meaning that beams of light can’t be overlayed to combine their heat.

Question: “If a person wanted to read all of the governing documents that apply to them—from the federal and state constitutions, treaties, agency-issued regulations, federal and state laws, local ordinances, etc.—how many pages would they have to read?” (255).

Munroe bases his analysis on the laws affecting himself as a resident of downtown Massachusetts, in the US. Numerous pages of relevant law from a range of sources would apply, and though many would not apply to him, he finds that the only way to know whether they do would be to read them. Reading all the potentially relevant legal documents would take 45 years total, or seven years if you just read the Supreme Court’s rulings in place of the bylaws of other districts.

This chapter lists several submitted questions that the author does not answer but instead responds to via small comics or doodles.

Question: “If I were to jump into a container of liquid nitrogen (or dispose of a body that way), how deep would it have to be for me/them to shatter into frozen pieces at the bottom?” (262).

A figure holding a body bag claims to need the answer by Friday.

Question: “What would happen to you if a colony of ants suddenly appeared in your bloodstream all at once?” (262).

A drawing depicts a doctor saying that the blood test came back with the result “bitey.”

Question: “If Harry Potter forgets where the invisible entrance to Platform 9¾ is, how long would he have to crash into walls randomly before discovering it?” (262)

A drawing depicts a figure, presumably Harry Potter, running face-first into a wall.

Question: “How long would it take for a single person to fill up an entire swimming pool with their own saliva?” (263).

The average person produces approximately half a liter per day, so if all saliva were dedicated to the task, it would take about one year to fill a bathtub. It would take a single person 8,345 years to fill a four-foot-deep swimming pool of 50 meters by 25 meters.

Question: “What if I tried to roll a snowball from the top of Mount Everest? How big would the snowball be by the time it reached the bottom and how long would it take?” (268).

The snowball would roll five kilometers down the main face of Everest, theoretically passing through enough snow to grow to 10-20 meters wide. However, snow on Everest is too dry to make a rolling snowball grow, so the snowball would simply roll down like any other object. Additionally, the tensile strength of snow is not strong enough to hold together a snowball larger than one to two meters wide. Slopes with wet, sticky snow are rare because the process of snowballs growing, falling apart, and growing again culminates in avalanches.

Question: “What would happen if one tried to funnel Niagara Falls through a straw?” (272).

You would get in trouble with the various regulatory bodies that dictate the minimum flow of water over the falls. It would be impossible to force that much water through a straw because water cannot travel faster than the speed of sound through water. At high speeds, “cavitation” would cause the water to boil into steam, reducing its flow below this threshold. The water would have to travel at a quarter of the speed of light to pass through a straw, at which speed everything would become plasma, nuclear reactions would occur, and it would have the energy output of a star.

Question: “What if you decided to walk from Austin, Texas, to New York City, but every step you take takes you back 30 days?” (277).

Every second spent walking would see you travel 50 days back in time, arriving in New York after a little over 3 weeks of walking, approximately 300,000 years in the past. (Munroe describes various major historical events and periods that would pass by in reverse as you traveled.)

Question: “What would happen if you fed ammonia into your stomach through a tube? How fast must the flow rate be to burn your stomach from the heat released? What would the newly created chlorine gas do to your stomach?” (284).

Chlorine gas would not be produced. Instead, the neutralization reaction between the ammonia and your stomach acid would produce the salt ammonium chloride and enough heat to burn your stomach lining. Not all the ammonia would be neutralized, and the remainder would cause several different types of serious tissue damage to your internal organs.

Question: “My son (5 years old) asked me today: If there were a kind of a fireman’s pole from the Moon down to the Earth, how long would it take to slide all the way from the Moon to the Earth?” (287).

It would be impossible to construct a pole between Earth and the moon because they rotate at different speeds, the distance between the two bodies changes, and gravity would tear the pole in half. Ignoring this technicality, it would take a few years to reach Earth. Most of this time would be spent climbing the pole against the Moon’s gravity until you reached the “L1 Lagrange Point,” at which Earth’s gravity would take over and begin to pull you down the pole. Upon approach, you would have to focus on slowing your speed to avoid burning up in the atmosphere and then contend with Mach 1 supersonic winds near Earth’s surface, before letting go around airplane cruising altitudes to parachute down.

In this chapter, the author answers several user-submitted questions via a brief written answer, a short comic, or both.

Question: “Could life evolve in a constantly running microwave?” (298).

The answer is what you would expect: No.

Question: “[…] It occurred to me that it might be possible to throw a cup of water hard enough that the container of water would go through the wall. Is this possible?” (299).

This is possible; anything can go through a wall if it has enough force behind it.

Question: “How slow would you have to chew in order to be able to infinitely consume breadsticks?” (299).

Divide a 140-calorie Olive Garden breadstick into 20 bites and then chew each bite 200 times at a rate of one second per chew to have infinite breadsticks.

Question: “If you were somehow to remove the white and yolk from inside an eggshell (chicken), and replace them with helium, would the eggshell float in the air?” (300).

No, there’s not enough of a cavity to compensate for the weight of the shell regardless of its contents.

Question: “What would stars smell like, if it were possible to smell them?” (301).

They would smell bad, like burning rubber or bleach, similar to the scents described when naval cavities are irradiated in cancer treatment. They would taste sour due to free hydrogen ions.

Question: “What is the average size for every man-made object on the planet?” (303).

The average size for every man-made object on the planet is average.

The final question is simply the letter “E” repeated. The author sympathizes.

Question: “From my 7-year-old son, Owen: How many snowflakes would it take to cover the entire world in 6 feet of snow? (I don’t know why 6 feet…but that’s what he asked.)” (305).

It would take approximately 10²³ snowflakes. If all the water in the world’s clouds fell at once, it would provide one inch of rain if evenly distributed across the world, or three to four inches if it fell just over the land. One inch of rain is equal to one foot of snow, but as more snow falls, the bottom layers are compressed under the weight of fresh snow, decreasing its overall depth. The US National Weather Service has highly specific guidelines to regulate the measuring of snowfall for this reason.

Question: “Assuming 1 out of every 4 people has a 5-year-old dog, and the dog reproduces once every year, with 5 puppies, and the puppies start reproducing at 5 and stop at 15 and die at 20, how long would it take for the Earth to be flooded with puppies, assuming we have all the food, water, and oxygen to sustain them?” (308).

There would be a population of 2 billion dogs to start with, which is already more dogs than currently exist. The dog population in any given year can be estimated by the simple exponential function: f(t) ≈ 6x10⁹x1.6578^t. (Munroe lists a series of landmark numbers of dogs over the ensuing years: After one year, there would be 12 billion dogs; in the sixth year, there would be 101 dogs per person; and after 25-30 years, dogs would cover the whole of the world’s land and begin stacking on top of each other. After 110 years, the gravitational pull of the dog population would be strong enough for them to undergo relativistic collapse.

Question: “When I was about 8 years old, shoveling snow on a freezing day in Colorado, I wished that I could be instantly transported to the surface of the Sun, just for a nanosecond, then instantly transported back. I figured this would be long enough to warm me up but not long enough to harm me. What would actually happen?” (314).

You can go anywhere if you go for a short enough period of time. The sun’s surface wouldn’t even warm you in a nanosecond, however; you would simply register a brief flash of dim light. The inside of the sun, however, would give you second-degree burns in one millionth of that time, and the short-wavelength light would cook your organs and ionize your DNA before even that.

Question: “Assuming that SPF works as it purports, what SPF would you need for a 1-hour trip to the surface of the Sun?” (318).

Theoretically, you would need SPF 1.3 million to be protected on the surface of the sun, the equivalent of five layers of SPF 20 sunscreen. However, in actual practice, this wouldn’t work, primarily because sunscreen would protect you from the UV rays in space and from the sun’s UV rays but not from the sun’s heat. If you were encased in a large enough ball of sunscreen, it might last long enough to protect you even as the outer layers melted away (but Munroe doesn’t recommend it).

Question: “After the Sun runs out of fuel, it will become a white dwarf and slowly cool. When will it be cool enough to touch?” (323)

The sun will collapse into a white dwarf star in approximately five billion years and will then cool to room temperature over the next 10 to 20 billion years. The gravitational pull of the white dwarf will be approximately 10 times that of Earth, so any spacecraft would almost certainly crash upon approach, and no human could survive on the surface. There’s no way to touch a star and survive, except perhaps vicariously via a robot probe small enough to endure the pressure.

Question: “What if all the raindrops were lemon drops and gumdrops?” (329).

The first rainfall would be delicious, but the buildup of fallen candy and the lack of fresh rainwater would soon lead to the collapse of society and the extinction of humanity. The layer of sugar blanketing the planet would lead to massive carbon dioxide emissions and a runaway feedback loop of global warming that would leave Earth’s climate similar to that of Venus, utterly inhospitable to life.