what if?

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Not to be confused with 17: What If.

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what if? is a blog hosted on the xkcd.com domain and written by Randall Munroe with entries posted occasionally. Before publishing the what if? book, articles were posted weekly.

On the blog, Randall uses his degree in physics and strong scientific background to discuss hypothetical physics questions apparently submitted by readers. Since 2014, there's also a book of the blog.

Unlike other sites which answer readers' questions, what if? typically takes the question beyond the original scope likely intended by the reader and takes it to some extreme for humorous effect. For example, in the first article, he discusses what would happen if a baseball were pitched at 90% of the speed of light. After effectively describing what would occur as a nuclear explosion, leveling the stadium and the surrounding mile radius, he concludes with the note "A careful reading of official Major League Baseball Rule 6.08(b) suggests that in this situation, the batter would be considered 'hit by pitch', and would be eligible to advance to first base."

The questions Randall tackles range from realistic possibilities (e.g. the probability of achieving a perfect SAT score by guessing) to completely fictional questions (e.g. How much Force power can Yoda output?). In his explanations, Randall, often uses diagrams in an xkcd style. Regardless of the context, Randall tends to take the questions extremely literally and responds seriously to them, even if they are whimsical (such as the Yoda question). This is clear from his response to the question of what would happen if everybody on Earth stood together and jumped at the same time. After acknowledging that the question has been answered elsewhere, he recaps the result, but then focuses more intently on the unasked resulting issue of the aftermath of everyone on Earth being magically transported to one location as they all try to return home.

This site is not under Creative Commons Attribution-NonCommercial 2.5 License like xkcd is.


Contents

[edit] Release schedule

  • The two first articles were released on the same day, Tuesday July 10, 2012, probably to get the blog going, and let users of xkcd see that there was going to be more.
    • After that they were released weekly for almost three years, with just a few times with two (and once three) weeks between releases, up until article 136 was released on April 12, 2015 (2 years and 40 weeks).
    • First after 25 releases was there a two week Christmas break before article 26 was released on December 31, 2012.
    • After that there were five more two weeks break, one three week break (before December 11, 2014) and two releases in a row (133-134 towards the end of this period of 136 articles), where the release dates where shifted so the two came out over three weeks' time with about 1.5 weeks between them.
    • The second break came a year after the first and was also a Christmas break before article 77 was released on December 31, 2013
    • Then from August 2014 there came several two week breaks, one in August, one i September and two in November, the last lasting three weeks into December, and on top of that the normal two weeks Christmas break.
    • After this less orderly period there came a period of 10 weeks in a row with 10 releases starting on January 1, 2015.
  • The release day was fixed to once a week on a given weekday, except for a few articles that were delayed a day (or two) in one week, but then next week's article would again be released on the normal day.
    • To begin with the released day was Tuesdays, and the third article was released a week after the first two on Tuesday July 17, 2012.
    • The release day shifted to Wednesday from article 100 released on Wednesday June 11, 2014.
    • The release day shifted once more to Thursday from article 117 released on Thursday October 23, 2014.
    • The final six articles in this period were released on four different week days, only two of them with one week apart.
  • The result of the above is that over the first 144 weeks 136 articles where released with never more than 3 weeks between releases. As the first two were released on week 1, this means that there were 134 articles released over the next 143 weeks, meaning there were only 9 weeks without an article.
  • But after article 136 was released on April 12, 2015, Randal took a 13 weeks break from updates until July 14, 2015.
    • At the time Randall wrote a note stating "What If updates are temporarily on hold, and will resume on July 14th, 2015 at 7:49:59 AM EDT."
    • This was the date and time that the New Horizons probe achieved its closest approach to Pluto.
    • The article 137 from July 14, 2015 was about the New Horizons probe.
  • After the break only three articles were released, two more were released after article 137 over three weeks, the last article 139 released on August 4, 2015.
    • But then there where two more breaks, so only one more article where released in, 2015, with article 150 released after more than 6 weeks on September 18, 2015.
  • First after 17 more weeks releases began again with article 141 on Tuesday January 16, 2016.
    • After than articles began coming out regularly with a total of 9 releases out before the end of March 2016, mainly on Tuesdays to begin with then one on a Friday before the last two came on Saturdays with two weeks breaks before each, the last being article 149 on March 26, 2016.
  • Since then only two more articles have been released with about 8 weeks between them.
    • So at the moment of writing this, summer 2016, it seems it is down to about one release every two months.
  • See more details for breaks in the releases in the table with a list of all the articles down below.

[edit] The book

Randall announced his what if? book on 12 March 2014 in the blag. It was published on September 2, 2014, and the UK edition of the book was published on September 4, 2014. It is the 2nd book published by Randall.

The general cover of the book

It is just like 'xkcd:volume 0' a compilation of some questions from the website, but half of them are new.

In the UK edition of the book, Randall included a preface about his thoughts on the units used in the UK. (The Metric System)

[edit] Summary

The summary on the back of the book reads:

Randall Munroe left NASA in 2005 to start up his hugely popular site XKCD 'a web comic of romance, sarcasm, math and language' which offers a witty take on the world of science and geeks. It now has 600,000 to a million page hits daily. Every now and then, Munroe would get emails asking him to arbitrate a science debate. 'My friend and I were arguing about what would happen if a bullet got struck by lightning, and we agreed that you should resolve it . . . ' He liked these questions so much that he started up What If.

  • If your cells suddenly lost the power to divide, how long would you survive?
  • How dangerous is it, really, to be in a swimming pool in a thunderstorm?
  • If we hooked turbines to people exercising in gyms, how much power could we produce?
  • What if everyone only had one soulmate?
  • When (if ever) did the sun go down on the British empire?
  • How fast can you hit a speed bump while driving and live?
  • What would happen if the moon went away?

In pursuit of answers, Munroe runs computer simulations, pores over stacks of declassified military research memos, solves differential equations, and consults with nuclear reactor operators. His responses are masterpieces of clarity and hilarity, studded with memorable cartoons and infographics. They often predict the complete annihilation of humankind, or at least a really big explosion. Far more than a book for geeks, WHAT IF: Serious Scientific Answers to Absurd Hypothetical Questions explains the laws of science in operation in a way that every intelligent reader will enjoy and feel much the smarter for having read.

The summary on the back of the UK edition of the book reads:

Hey! Thanks for looking at my book. If you're thinking about buying it, here are some things you might want to know:

Humans can't digest the cellulose in paper, but if we could, eating this book would give you about 2,300 calories (including the cover).

This book can't stop most bullets; if you want to use it for armour, you may want a lot more than one copy.

If you have a good arm, you could probably throw this book about 45 feet. With practice, it's possible to throw a book every 800 milliseconds, which means that if human attackers are sprinting towards you, you'll have three or four chances to hit them before they reach you. If, on the other hand, you're being attacked by a coyote, it's higher top speed means you'll have only one chance to hit it. Aim carefully.

HIDDEN FEATURE: The inside of this book has words and pictures, plus a special UK foreword. It answers many important questions, including whether you could jump from a plane with a helium tank and inflate balloons fast enough to slow your fall and survive (yes) and whether you could hide from a supersonic windstorm in Finland (yes, but it won't help).

[edit] Trivia

  • There is an easy way to link to a given what if? story by using a template. For instance write the following:
    • See the [[what if?]] ''{{what if|147|Niagara Straw}}''.
  • Copy paste the above text and correct the number and the title to get this result:

[edit] Articles

  • Below is a list of the articles released in the what if? blog.
    • This list can also be found in the acrhive section on the what if? blog.
    • But here more data can be added...
No. Title Release date Weeks since last release Question(s) answered / Topic Comment/Short note on subject
1 Relativistic Baseball July 10, 2012 What would happen if you tried to hit a baseball pitched at 90% the speed of light? The very first what if?
2 SAT Guessing July 10, 2012 0.0 What if everyone who took the SAT guessed on every multiple-choice question? How many perfect scores would there be? This second article was released on the same day as the first, probably to get the blog going, and let users of xkcd see that there was going to be more.
3 Yoda July 17, 2012 1.0 How much Force power can Yoda output? First regular release. From here on standard release day was Tuesday.
4 A Mole of Moles July 24, 2012 1.0 What would happen if you were to gather a mole (unit of measurement) of moles (the small furry critter) in one place?
5 Robot Apocalypse July 31, 2012 1.0 What if there was a robot apocalypse? How long would humanity last?
6 Glass Half Empty August 7, 2012 1.0 What if a glass of water was, all of a sudden, literally half empty?
7 Everybody Out August 14, 2012 1.0 Is there enough energy to move the entire current human population off-planet?
8 Everybody Jump August 21, 2012 1.0 What would happen if everyone on earth stood as close to each other as they could and jumped, everyone landing on the ground at the same instant?
9 Soul Mates August 28, 2012 1.0 What if everyone actually had only one soul mate, a random person somewhere in the world?
10 Cassini September 4, 2012 1.0 What would the world be like if the land masses were spread out the same way as now - only rotated by an angle of 90 degrees?
11 Droppings September 11, 2012 1.0 If you went outside and lay down on your back with your mouth open, how long would you have to wait until a bird pooped in it?
12 Raindrop September 18, 2012 1.0 What if a rainstorm dropped all of its water in a single giant drop?
13 Laser Pointer September 25, 2012 1.0 If every person on Earth aimed a laser pointer at the Moon at the same time, would it change color?
14 Short Answer Section October 2, 2012 1.0
  • How long would the Sun last if a giant water hose were focused upon it? My sixth grade brother, Adam, asked me this.
  • What if you shined a flashlight (or a laser) into a sphere made of one-way mirror glass?
  • If Michael Phelps could hold his breath indefinitely, how long would it take for him to reach the lowest point in the ocean and back if he swam straight down and then straight back up?
  • In the first Superman movie, Superman flies around Earth so fast that it begins turning in the opposite direction. This somehow turns back time [... ] How much energy would someone flying around the Earth have to exert in order to reverse the Earth's rotation?
  • How fast would you have to go in your car to run a red light claiming that it appeared green to you due to the Doppler Effect?
  • What would happen if you opened a portal between Boston (sea level) and Mexico City (elev. 8000+ feet)?
  • When my wife and I started dating she invited me over for dinner at one time. Her kitchen had something called Bauhaus chairs, which are full of holes, approx 5-6 millimeters in diameter in both back and seat. During this lovely dinner I was forced to liberate a small portion of wind and was relieved that I managed to do so very discretely. Only to find that the chair I sat on converted the successful silence into a perfect, and loud, flute note. We were both (luckily) amazed and surprised and I have often wondered what the odds are for something like that happening. We kept the chairs for five years but despite laborious attempts it couldn't be reproduced.
15 Mariana Trench Explosion October 9, 2012 1.0 What if you exploded a nuclear bomb (say, the Tsar Bomba) at the bottom of the Marianas Trench?
16 Today's topic: Lightning October 16, 2012 1.0
  • How dangerous is it, really, to be in a pool during a thunderstorm?
  • What would happen if you were taking a shower when you were struck by lightning? Or standing under a waterfall?
  • What would happen if you were in a boat or a plane that got hit by lightning? Or a submarine?
  • What if you were changing the light at the top of a radio tower and lightning struck? Or what if you were doing a backflip? Or standing in a graphite field? Or looking straight up at the bolt?
  • What would happen if lightning struck a bullet in midair?
  • What if you were flashing your BIOS during a thunderstorm and you got hit by lightning?
17 Green Cows October 23, 2012 1.0 If cows could photosynthesize, how much less food would they need?
18 BB Gun October 30, 2012 1.0 In Armageddon, a NASA guy comments that a plan to shoot a laser at the asteroid is like “shooting a b.b. gun at a freight train.” What would it take to stop an out-of-control freight train using only b.b. guns?
19 Tie Vote November 6, 2012 1.0 What if there's LITERALLY a tie? The release date in the archive is the wrong year 2013.
20 Diamond November 13, 2012 1.0 If a meteor made out of diamond and 100 feet in diameter was traveling at the speed of light and hit the earth, what would happen to it?
21 Machine Gun Jetpack November 20, 2012 1.0 Is it possible to build a jetpack using downward firing machine guns?
22 Cost of Pennies November 27, 2012 1.0 If you carry a penny in your coin tray, how long would it take for that penny to cost you more than a cent in extra gas?
23 Short Answer Section II December 4, 2012 1.0
  • If my printer could literally print out money, would it have that big an effect on the world?
  • What would happen if you exploded a nuclear bomb in the eye of a hurricane? Would the storm cell be immediately vaporized?
  • If everyone put little turbine generators on the downspouts of their houses and businesses, how much power would we generate? Would we ever generate enough power to offset the cost of the generators?
  • Using only pronounceable letter combinations, how long would names have to be to give each star in the universe a unique one word name?
  • I bike to class sometimes. It's annoying biking in the wintertime, because it's so cold. How fast would I have to bike for my skin to warm up the way a spacecraft heats up during reentry?
  • How much physical space does the internet take up?
  • What if you strapped C4 to a boomerang? Could this be an effective weapon, or would it be as stupid as it sounds?
24 Model Rockets December 11, 2012 1.0 How many model rocket engines would it take to launch a real rocket into space?
25 Three Wise Men December 18, 2012 1.0 The story of the three wise men got me wondering: What if you did walk towards a star at a fixed speed? What path would you trace on the Earth? Does it converge to a fixed cycle?
26 Leap Seconds December 31, 2012 1.9 Every now and then we have to insert a leap second because the Earth’s rotation is slowing down. Could we speed up Earth’s rotation, so that we do not need Leap Seconds? The first two weeks Christmas break
27 Death Rates January 8, 2013 1.1 If one randomly chosen extra person were to die each second somewhere on Earth, what impact would it have on the world population?
28 Steak Drop January 15, 2013 1.0 From what height would you need to drop a steak for it to be cooked when it hit the ground?
29 Spent Fuel Pool January 22, 2013 1.0 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?
30 Interplanetary Cessna January 29, 2013 1.0 What would happen if you tried to fly a normal Earth airplane above different Solar System bodies?
31 FedEx Bandwidth February 5, 2013 1.0 When - if ever - will the bandwidth of the Internet surpass that of FedEx?
32 Hubble February 12, 2013 1.0 If the Hubble telescope were aimed at the Earth, how detailed would the images be?
33 Ships February 19, 2013 1.0 How much would the sea level fall if every ship were removed all at once from the Earth's waters?
34 Twitter February 26, 2013 1.0 How many unique English tweets are possible? How long would it take for the population of the world to read them all out loud?
35 Hair Dryer March 5, 2013 1.0 What would happen if a hair dryer with continuous power was turned on and put in an airtight 1x1x1 meter box?
36 Cornstarch March 12, 2013 1.0 How much cornstarch can I rinse down the drain before unpleasant things start to happen?
37 Supersonic Stereo March 19, 2013 1.0 What if you somehow managed to make a stereo travel at twice the speed of sound, would it sound backwards to someone who was just casually sitting somewhere as it flies by?
38 Voyager March 26, 2013 1.0 With today's technology, would it be possible to launch an unmanned mission to retrieve Voyager I?
39 Hockey Puck April 2, 2013 1.0 How hard would a puck have to be shot to be able to knock the goalie himself backwards into the net?
40 Pressure Cooker April 9, 2013 1.0 Am I right to be afraid of pressure cookers? What's the worst thing that can happen if you misuse a pressure cooker in an ordinary kitchen?
41 Go West April 16, 2013 1.0 If everybody in the US drove west, could we temporarily halt continental drift?
42 Longest Sunset April 23, 2013 1.0 What is the longest possible sunset you can experience while driving, assuming we are obeying the speed limit and driving on paved roads?
43 Train Loop April 30, 2013 1.0 Could a high-speed train run through a vertical loop, like a rollercoaster, with the passengers staying comfortable?
44 High Throw May 7, 2013 1.0 How high can a human throw something?
45 ISS Music Video May 14, 2013 1.0 Is this the most expensive music video ever?
46 Bowling Ball May 21, 2013 1.0 I've been told that if the Earth were shrunk down to the size of a bowling ball, it would be smoother than said bowling ball. My question is, what would a bowling ball look like if it were blown up to the size of the Earth?
47 Alien Astronomers May 28, 2013 1.0 Let's assume there's life on the the nearest habitable exoplanet and that they have technology comparable to ours. If they looked at our star right now, what would they see?
48 Sunset on the British Empire June 4, 2013 1.0 When (if ever) did the Sun finally set on the British Empire?
49 Sunless Earth June 11, 2013 1.0 What would happen to the Earth if the Sun suddenly switched off?
50 Extreme Boating June 18, 2013 1.0 What would it be like to navigate a rowboat through a lake of mercury? What about bromine? Liquid gallium? Liquid tungsten? Liquid nitrogen? Liquid helium?
51 Free Fall June 25, 2013 1.0 What place on Earth would allow you to freefall the longest by jumping off it? What about using a squirrel suit?
52 Bouncy Balls July 2, 2013 1.0 What if one were to drop 3,000 bouncy balls from a seven story parking structure onto a person walking on the sidewalk below? Should the person survive, what would be the number of bouncy balls needed to kill them? What injuries would occur and what would the associated crimes be? The release date in the archive is the wrong month June.
53 Drain the Oceans July 9, 2013 1.0 How quickly would the ocean's drain if a circular portal 10 meters in radius leading into space was created at the bottom of Challenger Deep, the deepest spot in the ocean? How would the Earth change as the water is being drained?
54 Drain the Oceans: Part II July 16, 2013 1.0 Supposing you did Drain the Oceans, and dumped the water on top of the Curiosity rover, how would Mars change as the water accumulated?
55 Random Sneeze Call July 23, 2013 1.0 If you call a random phone number and say “God bless you”, what are the chances that the person who answers just sneezed? On average, not just in spring or fall.
56 Restraining an Airplane July 30, 2013 1.0 If you wanted to anchor an airplane into the ground so it wouldn't be able to take off, what would the rope have to be made out of?
57 Dropping a Mountain August 6, 2013 1.0 What if a huge mountain—Denali, say—had the bottom inch of its base disappear? What would happen from the impact of the mountain falling 1 inch? What about 1 foot? What if the mountain's base were raised to the present height of the summit, and then the whole thing were allowed to drop to the earth?
58 Orbital Speed August 12, 2013 0.9
  • What if a spacecraft slowed down on re-entry to just a few miles per hour using rocket boosters like the Mars-sky-crane? Would it negate the need for a heat shield?
  • Is it possible for a spacecraft to control its reentry in such a way that it avoids the atmospheric compression and thus would not require the expensive (and relatively fragile) heat shield on the outside?
  • Could a (small) rocket (with payload) be lifted to a high point in the atmosphere where it would only need a small rocket to get to escape velocity?
59 Updating a Printed Wikipedia August 20, 2013 1.1 If you had a printed version of the whole of (say, the English) Wikipedia, how many printers would you need in order to keep up with the changes made to the live version?
60 Signs of Life August 27, 2013 1.0 If you could teleport to a random place of the surface of the Earth, what are the odds that you'll see signs of intelligent life?
61 Speed Bump September 3, 2013 1.0 How fast can you hit a speed bump while driving and live?
62 Falling With Helium September 10, 2013 1.0 What if I jumped out of an airplane with a couple of tanks of helium and one huge, un-inflated balloon? Then, while falling, I release the helium and fill the balloon. How long of a fall would I need in order for the balloon to slow me enough that I could land safely?
63 Google's Datacenters on Punch Cards September 17, 2013 1.0 If all digital data were stored on punch cards, how big would Google's data warehouse be?
64 Rising Steadily September 24, 2013 1.0 If you suddenly began rising steadily at one foot per second, how exactly would you die? Would you freeze or suffocate first? Or something else?
65 Twitter Timeline Height October 1, 2013 1.0 If our Twitter timelines (tweets by the people we follow) actually extended off the screen in both directions, how tall would they be?
66 500 MPH October 8, 2013 1.0 If winds reached 500 mph, would it pick up a human?
67 Expanding Earth October 15, 2013 1.0 How long would it take for people to notice their weight gain if the mean radius of the world expanded by 1cm every second? (Assuming the average composition of rock were maintained.)
68 Little Planet October 22, 2013 1.0 If an asteroid was very small but supermassive, could you really live on it like the Little Prince?
69 Facebook of the Dead October 29, 2013 1.0 When, if ever, will Facebook contain more profiles of dead people than of living ones?
70 The Constant Groundskeeper November 5, 2013 1.0 How big of a lawn would you have to have so that when you finished mowing you'd need to start over because the grass has grown?
71 Stirring Tea November 12, 2013 1.0 I was absentmindedly stirring a cup of hot tea, when I got to thinking, "aren't I actually adding kinetic energy into this cup?" I know that stirring does help to cool down the tea, but what if I were to stir it faster? Would I be able to boil a cup of water by stirring?
72 Loneliest Human November 19, 2013 1.0 What is the furthest one human being has ever been from every other living person? Were they lonely?
73 Lethal Neutrinos November 26, 2013 1.0 How close would you have to be to a supernova to get a lethal dose of neutrino radiation?
74 Soda Planet December 3, 2013 1.0 How much of the Earth's currently-existing water has ever been turned into a soft drink at some point in its history?
75 Phone Keypad December 10, 2013 1.0 I use one of those old phones where you type with numbers—for example, to type "Y", you press 9 three times. Some words have consecutive letters on the same number. When they do, you have to pause between letters, making those words annoying to type. What English word has the most consecutive letters on the same key?
76 Reading Every Book December 17, 2013 1.0 At what point in human history were there too many (English) books to be able to read them all in one lifetime?
77 Growth Rate December 31, 2013 2.0 What height would humans reach if we kept growing through our whole development period (i.e. till late teens/early twenties) at the same pace as we do during our first month? The second two weeks Christmas break
78 T-rex Calories January 7, 2014 1.0 If a T-rex were released in New York City, how many humans/day would it need to consume to get its needed calorie intake?
79 Lake Tea January 14, 2014 1.0 What if we were to dump all the tea in the world into the Great Lakes? How strong, compared to a regular cup of tea, would the lake tea be?
80 Pile of Viruses January 21, 2014 1.0 What if every virus in the world were collected into one area? How much volume would they take up and what would they look like?
81 Catch! January 28, 2014 1.0 Is there any way to fire a gun so that the bullet flies through the air and can then be safely caught by hand? e.g. shooter is at sea level and catcher is up a mountain at the extreme range of the gun.
82 Hitting a comet February 5, 2014 1.1 Astrophysicists are always saying things like "This mission to this comet is equivalent to throwing a baseball from New York and hitting a particular window in San Francisco." Are they really equivalent?
83 Star Sand February 11, 2014 0.9 If you made a beach using grains the proportionate size of the stars in the Milky Way, what would that beach look like?
84 Paint the Earth February 18, 2014 1.0 Has humanity produced enough paint to cover the entire land area of the Earth?
85 Rocket Golf February 25, 2014 1.0 Assuming that you have a spaceship in orbit around the Earth, could you propel your ship to speeds exceeding escape velocity by hitting golf balls in the other direction? If so, how many golf balls would be required to reach the Moon?
86 Far-Traveling Objects March 4, 2014 1.0 In terms of human-made objects, has Voyager 1 travelled the farthest distance? It's certainly the farthest from Earth we know about. But what about the edge of ultracentrifuges, or generator turbines that have been running for years, for example?
87 Enforced by Radar March 11, 2014 1.0 I've occasionally seen "radar enforced" on speed limit signs, and I can't help but ask: How intense would radio waves have to be to stop a car from going over the speed limit, and what would happen if this were attempted?
88 Soda Sequestration March 18, 2014 1.0 How much CO2 is contained in the world's stock of bottled fizzy drinks? How much soda would be needed to bring atmospheric CO2 back to preindustrial levels?
89 Tungsten Countertop March 25, 2014 1.0 How far would a tungsten countertop descend if I dropped it into the Sun?
90 Great Tree, Great Axe April 3, 2014 1.3

If all the seas were one sea,
What a great sea that would be!
If all the trees were one tree,
What a great tree that would be!
If all the men were one man,
What a great man that would be!
If all the axes were one axe,
What a great axe that would be!
And if the great man took the great axe,
And cut down the great tree,
And let if fall into the great sea,
What a great splish-splash that would be!
... How great would all of these things be?

91 Faucet Power April 8, 2014 0.7 I just moved into a new apartment. It includes hot water but I have to pay the electric bill. So being a person on a budget ... what's the best way to use my free faucet to generate electricity?
92 One-Second Day April 15, 2014 1.0 What would happen if the Earth's rotation were sped up until a day only lasted one second?
93 Windshield Raindrops April 22, 2014 1.0 At what speed would you have to drive for rain to shatter your windshield?
94 Billion-Story Building April 29, 2014 1.0 My daughter — age 4.5 — maintains she wants a billion-story building. It turns out not only is that hard to help her appreciate this size, I am not at all able to explain all of the other difficulties you'd have to overcome.
95 Pyramid Energy May 6, 2014 1.0 What took more energy, the building of the Great Pyramid of Giza or the Apollo Mission? If we could convert the energy to build the Great Pyramid, would it be enough to send a rocket to the Moon and back?
96 $2 Undecillion Lawsuit May 14, 2014 1.1 What if Au Bon Pain lost this lawsuit and had to pay the plaintiff $2 undecillion?
97 Burning Pollen May 20, 2014 0.9 What if you were to somehow ignite the pollen that floats around in the air in spring? Other than being a really bad idea, what effect would it have?
98 Blood Alcohol May 27, 2014 1.0 Could you get drunk from drinking a drunk person's blood?
99 Starlings June 3, 2014 1.0 I was watching this video and was wondering: How many birds there would need to be for gravity to take over and force them into a gargantuan ball of birds?
100 WWII Films June 11, 2014 1.1 Did WWII last longer than the total length of movies about WWII? For that matter, which war has the highest movie time:war time ratio? From here on standard release day was Wednesday.
101 Plastic Dinosaurs June 18, 2014 1.0 As plastic is made from oil and oil is made from dead dinosaurs, how much actual real dinosaur is there in a plastic dinosaur?
102 Keyboard Power June 25, 2014 1.0 As a writer, I'm wondering what would be the cumulative energy of the hundreds of thousands of keystrokes required to write a novel.
103 Vanishing Water July 2, 2014 1.0 What would happen if all the bodies of water on Earth magically disappeared?
104 Global Snow July 9, 2014 1.0 From my seven-year-old son: How many snowflakes would it take to cover the entire world in six feet of snow? (I don't know why six feet...but that's what he asked.)
105 Cannibalism July 16, 2014 1.0 How long could the human race survive on only cannibalism?
106 Ink Molecules July 23, 2014 1.0 Suppose you were to print, in 12 point text, the numeral 1 using a common cheap ink-jet printer. How many molecules of the ink would be used? At what numerical value would the number printed approximately equal the number of ink molecules used?
107 Letter to Mom July 30, 2014 1.0 What’s the fastest way to get a hand-written letter from my place in Chicago to my mother in New Jersey?
108 Expensive Shoebox August 13, 2014 2.0 What would be the most expensive way to fill a size 11 shoebox (e.g. with 64 GB MicroSD cards all full of legally purchased music)? The third two weeks break.
109 Into the Blue August 20, 2014 1.0 If I shot an infinitely strong laser beam into the sky at a random point, how much damage would it do?
110 Walking New York August 27, 2014 1.0 Could a person walk the entire city of NY in their lifetime? (including inside apartments)
111 All the Money September 2, 2014 0.9 People sometimes say "If I had all the money in the world ..." in order to discuss what they would do if they had no financial constraints. I'm curious, though, what would happen if one person had all of the world's money?
112 Balloon Car September 17, 2014 2.1 My 12-year-old daughter is proposing an interesting project. She is planning to attach a number of helium balloons to a chair, which in turn would be tethered by means of a rope to a Ferrari. Her 13-year-old friend would then drive the Ferrari around, while she sits in the chair enjoying uninterrupted views of the countryside. Leaving aside the legal and insurance difficulties, my daughter is keen to know the maximum speed that she could expect to attain, and how many helium balloons would be required. The fourth two weeks break.
113 Visit Every State September 24, 2014 1.0 How fast could you visit all 50 states?
114 Antimatter October 1, 2014 1.0 What if everything was antimatter, EXCEPT Earth?
115 Into the Sun October 8, 2014 1.0 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?
116 No-Rules NASCAR October 15, 2014 1.0 If you stripped away all the rules of car racing and had a contest which was simply to get a human being around a track 200 times as fast as possible, what strategy would win? Let's say the racer has to survive.
117 Distant Death October 23, 2014 1.1 What is the farthest from Earth that any Earth thing has died? From here on standard release day was Thursday.
118 Physical Salary October 30, 2014 1.0 What if people's incomes appeared around them as cash in real time? How much would you need to make to be in real trouble?
119 Laser Umbrella November 13, 2014 2.0 Stopping rain from falling on something with an umbrella or a tent is boring. What if you tried to stop rain with a laser that targeted and vaporized each incoming droplet before it could come within ten feet of the ground? The fifth two weeks break.
120 Alternate Universe What Ifs November 20, 2014 1.0 Dispatches from a horrifying alternate universe
121 Frozen Rivers December 11, 2014 3.0 What would happen if all of the rivers in the US were instantly frozen in the middle of the summer? The only tree weeks break, the sixth break in total.
122 Lava Lamp December 18, 2014 1.0 What if I made a lava lamp out of real lava? What could I use as a clear medium? How close could I stand to watch it?
123 Fairy Demographics January 1, 2015 2.0 How many fairies would fly around, if each fairy is born from the first laugh of a child and fairies were immortal? The third two weeks Christmas break, the seventh break in total
124 Lunar Swimming January 8, 2015 1.0 What if there was a lake on the Moon? What would it be like to swim in it? Presuming that it is sheltered in a regular atmosphere, in some giant dome or something.
125 Bowling Ball January 15, 2015 1.0 You are in a boat directly over the Mariana Trench. If you drop a 7kg bowling ball over the side, how long would it take to hit the bottom?
126 Stairs January 22, 2015 1.0 If you made an elevator that would go to space (like the one you mentioned in the billion-story building) and built a staircase up (assuming regulated air pressure) about how long would it take to climb to the top?
127 Tug of War January 28, 2015 0.9 Would it be possible for two teams in a tug-o-war to overcome the ultimate tensile strength of an iron rod and pull it apart? How big would the teams have to be?
128 Zippo Phone February 5, 2015 1.1 What in my pocket actually contains more energy, my Zippo or my smartphone? What would be the best way of getting the energy from one to the other? And since I am already feeling like Bilbo in this one, is there anything else in my pocket that would have unexpected amounts of stored energy?
129 Black Hole Moon February 12, 2015 1.0 What would happen if the Moon were replaced with an equivalently-massed black hole? If it's possible, what would a lunar ("holar"?) eclipse look like?
130 Snow Removal February 19, 2015 1.0 I've long thought about putting a flamethrower on the front of a car to melt snow and ice before you drive across it. Now I've realized that a flamethrower is impractical, but what about a high-powered microwave emitter?
131 Microwaves February 27, 2015 1.1 I have had a particular problem for as long as I can remember. Any time I attempt to heat left over Chinese food in a microwave, it fails to heat completely through somewhere. Usually the center but not always and usually rice, but often it will be a small section of meat. It's baffling and has made me automatically adjust heating times to over 2 minutes. In most cases this tends to heat the bowl or plate more than the food. So I suppose the question is what is the optimal time to heat left over Chinese food in the microwave, how about an 800 watt microwave? The release date in the archive is the wrong year 2014. From here on there seems to no longer be a standard release day for some time.
132 Hotter than Average March 7, 2015 1.1 I saw a sign at a hot springs tub saying "Caution: Water is hotter than average" with water at about 39°C. Although they were presumably trying to say "hotter than the average swimming pool," this got me wondering: What is the average temperature of all water on the Earth’s surface, and how does that temperature compare to 39°C?
133 Flagpole March 17, 2015 1.4 So, you're falling from a height above the tallest building in your town, and you don't have a parachute. But wait! Partway down the side of that skyscraper there's a flagpole sticking out, sans flag! You angle your descent and grab the pole just long enough to swing around so that when you let go you're now heading back up toward the sky. As gravity slows you and brings you to a halt, you reach the top of the skyscraper, where you reach out and pull yourself to safety. What's the likelihood this could happen? The first of two longer shifts in release day two weeks in a row which resulted in only two releases over three weeks, resulting in the eight break in total.
134 Space Burial March 28, 2015 1.6 I've often joked I'd like to have my remains put into orbit. Not in a "scatter my ashes" sense, but, like, "throw my naked corpse out the airlock" sense. Honestly, my main motivation is to baffle someone in the distant future, but it's an interesting scientific question: what would happen to my body in orbit over the course of years, decades or centuries? The second of two longer shifts in release day two weeks in a row which resulted in only two releases over three weeks, resulting in the eight break in total.
135 Digging Downward April 5, 2015 1.1 What would happen if I dug straight down, at a speed of 1 foot per second? What would kill me first?
136 Spiders vs. the Sun April 12, 2015 1.0 Which has a greater gravitational pull on me: the Sun, or spiders? Granted, the Sun is much bigger, but it is also much further away, and as I learned in high school physics, the gravitational force is proportional to the square of the distance.
137 New Horizons July 14, 2015 13.3 What if New Horizons hits my car? The second longest break up til summer 2016, the only one to have been announced. The ninth break in total.
138 Jupiter Submarine July 28, 2015 2.0 What if you released a submarine into Jupiter's atmosphere? Would it eventually reach a point where it would float? Could it navigate? The sixth two weeks break, tenth break in total.
139 Jupiter Descending August 4, 2015 1.0 If you did fall into Jupiter's atmosphere in a submarine, what would it actually look like? What would you see before you melted or burned up?
140 Proton Earth, Electron Moon September 18, 2015 6.4 What if the Earth were made entirely of protons, and the Moon were made entirely of electrons? First and shortest of two long breaks in a row, the 11th break in total.
141 Sunbeam January 12, 2016 16.6 What if all of the sun's output of visible light were bundled up into a laser-like beam that had a diameter of around 1m once it reaches Earth? Second and longest break so far of two long breaks in a row, the 12th break in total. From here on standard release day was again Tuesday.
142 Space Jetta January 20, 2016 1.1 What if I tried to re-enter the atmosphere in my car? (a 2000 VW Jetta TDI). Would it do more environmental damage than it is already apparently doing?
143 Europa Water Siphon January 26, 2016 0.9 What if you built a siphon from the oceans on Europa to Earth? Would it flow once it's set up? (We have an idea for selling bottled Europa water.)
144 Saliva Pool February 2, 2016 1.0 How long would it take for a single person to fill up an entire swimming pool with their own saliva?
145 Fire From Moonlight February 9, 2016 1.0 Can you use a magnifying glass and moonlight to light a fire?
146 Stop Jupiter February 16, 2016 1.0 I understand that the New Horizons craft used gravity assist from Jupiter to increase its speed on the way to Pluto. I also understand that by doing this, Jupiter slowed down very slightly. How many flyby runs would it take to stop Jupiter completely?
147 Niagara Straw February 26, 2016 1.4 What would happen if one tried to funnel Niagara Falls through a straw? From here on there is no longer any standard release days.
148 Eat the Sun March 12, 2016 2.1 What percentage of the Sun's heat (per day) does the population of Earth eat in calories per year? What changes could be made to our diets for the amount of calories to equal the energy of the Sun? The seventh two weeks break, 13th break in total.
149 Pizza Bird March 26, 2016 2.0 My boyfriend recently took a flight on a plane with wifi, and while he was up there, wistfully asked if I could send him a pizza. I jokingly sent him a photo of a parrot holding a pizza slice in its beak. Obviously, my boyfriend had to go without pizza until he landed at JFK. But this raised the question: could a bird deliver a standard 20" New York-style cheese pizza in a box? And if so, what kind of bird would it take? The eight two weeks break, 14th break in total.
150 Tatooine Rainbow May 23, 2016 8.3 Since rainbows are caused by the refraction of the sunlight by tiny droplets of rainwater, what would rainbow look like on Earth if we had two suns like Tatooine? First two months break of at least two in a row, the 15th break in total.
151 Sun Bug July 21, 2016 8.4 How many fireflies would it take to match the brightness of the Sun? Second two months break of at least two in a row, the 16th break in total. The release date in the archive is the wrong month June. It was released between 18-20 July, as the link here was posted on the 20th. But on the archive page is says it was released on June 21, which should probably have been July 21.
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