All Q&As

February 18, 2019Does drinking beer before (rather than after) wine really prevent you from getting a hangover? (4104 answers, 76% correct)

October 1, 2012Steel is known for its hardness and strength, which it gets from: (2950 answers, 42% correct)

October 27, 2014What makes hairs turn white? (2867 answers, 11% correct)

December 19, 2016In Switzerland, the first minute of January 1, 2017 had 61 seconds instead of 60. Why is that? (2742 answers, 46% correct)

December 24, 2012Why do clothes shrink in the wash? (2620 answers, 77% correct)

July 22, 2013Which competency hinders language acquisition? (2521 answers, 19% correct)

November 5, 2012Which of these elements can be dated using the carbon-14 method? (2515 answers, 39% correct)

July 25, 2016Sexually frustrated male Drosophila flies: (2473 answers, 27% correct)

January 5, 2015Water vapor... (2466 answers, 42% correct)

March 30, 2015When one loses weight, what happens to most of the fat? (2459 answers, 38% correct)

July 7, 2014Why does inhaling helium change the voice’s pitch? (2412 answers, 59% correct)

September 14, 2015What would space smell like? (2402 answers, 27% correct)

September 22, 2014Why does slicing an onion make you cry? (2386 answers, 42% correct)

November 19, 2012In a microwave oven, a metal object will produce sparks because: (2326 answers, 35% correct)

February 6, 2018How can you get rid of garlic breath? (2323 answers, 57% correct)

July 3, 2017What causes oysters to become toxic? (2301 answers, 29% correct)

November 26, 2012Alcohol makes you drunk because: (2279 answers, 64% correct)

March 31, 2014Who steers a school of fish? (2262 answers, 81% correct)

February 16, 2015Where does the feeling of déjà-vu come from? (2259 answers, 33% correct)

June 30, 2014What causes non-random variations in the number of human births over the course of the year? (2247 answers, 40% correct)

August 19, 2013 Why do some planets have rings? (2222 answers, 28% correct)

March 18, 2013What should you avoid feeding to your dog? (2215 answers, 71% correct)

April 11, 2016Why do rats run alongside walls? (2211 answers, 49% correct)

July 11, 2018Which of the following do cherry pits contain? (2193 answers, 41% correct)

December 15, 2014What is the biggest danger facing someone who lives in Florida? (2167 answers, 48% correct)

February 11, 2013Which drink has the most caffeine? (2157 answers, 49% correct)

February 25, 2013Why do high voltage lines make noises? (2117 answers, 19% correct)

March 26, 2018A cat’s purr has the incredible ability to: (2116 answers, 66% correct)

August 28, 2017Which is the weakest force in the Universe? (2101 answers, 53% correct)

July 8, 2013What is the most used natural resource on earth after air and water? (2088 answers, 50% correct)

August 18, 2014What strategy should a mosquito adopt when it rains? (2083 answers, 32% correct)

February 27, 2012Why are the poles so cold? (1995 answers, 78% correct)

October 22, 2012What gives a chocolate bar its unique brittle texture? (1989 answers, 49% correct)

November 17, 2014Why does concrete harden? (1980 answers, 40% correct)

January 28, 2013Why have tomatoes become tasteless? (1971 answers, 25% correct)

February 24, 2014Why are your fingertips so wrinkled when you get out of the bath? (1955 answers, 28% correct)

March 5, 2012If a tunnel were drilled through the center of the earth, what would happen if you jumped in? (1951 answers, 60% correct)

September 20, 2010Can a sailing boat go faster than the wind? (1936 answers, 41% correct)

February 27, 2017The number of spots on a ladybug depends on: (1924 answers, 58% correct)

March 4, 2013Can beans be considered as? (1912 answers, 38% correct)

December 1, 2014How are you most likely to catch a cold in the winter? (1904 answers, 56% correct)

December 18, 2017Why don't actors wear green on stage? (1897 answers, 17% correct)

March 14, 2016What is the main source of heat on the EPFL campus? (1888 answers, 11% correct)

November 12, 2012We can eat the blue mold on roquefort cheese because: (1883 answers, 27% correct)

April 10, 2017Which of these contains the most protein? (1869 answers, 33% correct)

May 27, 2013Why do we yawn? (1865 answers, 33% correct)

May 18, 2015How can you get rid of a song that keeps playing over and over in your brain? (1861 answers, 42% correct)

October 14, 2013Why do astronauts on the International Space Station feel weightless? (1846 answers, 46% correct)

January 21, 2013Is it possible to change the trajectory of an asteroid? (1830 answers, 58% correct)

November 26, 2018Why is Greek yogurt not very environmentally friendly? (1806 answers, 39% correct)

September 9, 2013Why do humans need to get vitamin C from external sources? (1805 answers, 57% correct)

February 18, 2013Why does body hair grow to a different length from head hair? (1799 answers, 42% correct)

January 16, 2012What is the mass of a 1 kg object on Jupiter? (1791 answers, 47% correct)

September 23, 2013Why does white bread have the biggest holes? (1782 answers, 57% correct)

October 31, 2016Which sense do homing pigeons use to find their way when they are far from home? (1768 answers, 31% correct)

December 17, 2012In winter, the roads are salted to… (1759 answers, 43% correct)

December 3, 2012Why is the interior of the earth so hot? (1754 answers, 44% correct)

July 20, 2015Locusts become deaf: (1752 answers, 24% correct)

September 7, 2015Why do paper cuts hurt so much? (1748 answers, 28% correct)

July 2, 2012What’s the first thing humanity will run out of? (1734 answers, 30% correct)

February 20, 2012Ice skates glide across the ice because… (1728 answers, 63% correct)

October 6, 2014What record was recently broken in Antarctica? (1724 answers, 15% correct)

August 31, 2018One-way mirrors let you see people without them seeing you because: (1721 answers, 85% correct)

April 30, 2012The more bubbles there are in your champagne glass... (1717 answers, 63% correct)

October 13, 2014How does a rubber eraser remove gray pencil from paper? (1716 answers, 52% correct)

March 25, 2013Which of these cooking miracles is due to the use of baking soda? (1706 answers, 0% correct)

October 8, 2012Do flies sleep at night? (1702 answers, 68% correct)

January 11, 2017Why shouldn’t you eat grapefruit when taking certain medications? (1700 answers, 29% correct)

October 21, 2013Why can’t you tickle yourself? (1699 answers, 27% correct)

September 10, 2012How do you know when you're falling? (1679 answers, 21% correct)

May 29, 2012Why are lighter-colored eyes more sensitive to light? (1678 answers, 71% correct)

February 17, 2014In Switzerland, Föhn winds are so warm because: (1661 answers, 60% correct)

January 27, 2014If the ground was a magnet 20 times stronger than anything commercially available, we would … (1658 answers, 21% correct)

January 6, 2014Love, sweet love… What would our lives be without this tender emotion that makes us: (1656 answers, 54% correct)

March 26, 2012Why do waves break? (1644 answers, 36% correct)

August 25, 2014Why do extreme sportsmen go to the Amazon every spring? (1643 answers, 67% correct)

March 12, 2012Why does airing certain wines improve their flavor? (1639 answers, 29% correct)

April 15, 2013What is the origin of sea salt? (1627 answers, 73% correct)

July 16, 2012Water in the UAE boils at 94 degrees in certain places because (1612 answers, 40% correct)

January 14, 2013Why do some plants produce nicotine? (1612 answers, 54% correct)

February 22, 2016Why do airplanes have round windows? (1609 answers, 60% correct)

October 28, 2013Why Don’t We Act Out Our Dreams? (1600 answers, 32% correct)

January 13, 2014Why does popcorn explode when heated? (1598 answers, 75% correct)

October 11, 2016Which of the following drinks is least likely to slosh over the side when two glasses clink? (1598 answers, 37% correct)

January 24, 2017What will happen after the breakup of the Larsen C ice shelf in Antarctica? (1589 answers, 51% correct)

October 15, 2012How can you start a fire without creating a lot of smoke? (1587 answers, 72% correct)

September 17, 2012In four billion years, a collision between the Milky Way and Andromeda galaxies will: (1586 answers, 74% correct)

August 10, 2015All space debris is monitored from Earth, with the exception of: (1583 answers, 75% correct)

January 23, 2018What happens to owls’ sense of hearing as they get older? (1575 answers, 18% correct)

November 27, 2017What is the main cause of San Francisco’s ever-present fog? (1574 answers, 38% correct)

July 1, 2013What gives the sun its energy? (1573 answers, 66% correct)

October 29, 2012Your hair could withstand a weight of 12 tons due to: (1545 answers, 74% correct)

May 14, 2012In the International Space Station, an American astronaut tries to write down his Russian colleague’s phone number… (1534 answers, 49% correct)

August 26, 2013For one deciliter of coffee, which choice is the most energy-efficient, taking into account the entire chain of production? (1531 answers, 26% correct)

June 2, 2014Do flies think before they act? (1527 answers, 48% correct)

December 10, 2012Lake Geneva’s 30cm tides are caused by: (1520 answers, 26% correct)

September 12, 2016What could cause a lithium-ion battery to explode? (1519 answers, 54% correct)

June 29, 2015It is thought that water – maybe more than all the oceans put together – can be found over 400 km underground following the discovery of: (1509 answers, 32% correct)

April 2, 2012You can keep your balance on a bicycle because of: (1508 answers, 26% correct)

May 4, 2015Cows are more vulnerable to nearby lightning strikes than humans because of: (1502 answers, 37% correct)

December 21, 2015What is that whitish coating that sometimes appears on the surface of chocolate? (1499 answers, 51% correct)

September 30, 2013Why is a snake’s tongue forked? (1488 answers, 45% correct)

July 4, 2016The largest known bacteria are: (1483 answers, 57% correct)

August 12, 2013Which of these produces at least half the oxygen on Earth? (1480 answers, 69% correct)

November 25, 2013Why do flies rub their legs together? (1475 answers, 77% correct)

July 18, 2016What makes the Juno space probe so unique? (1472 answers, 44% correct)

February 4, 2013Fireflies produce light via … (1466 answers, 81% correct)

April 22, 2013Are There Earthquakes in Switzerland? (1460 answers, 78% correct)

June 17, 2013Where would you be exposed to the highest effective radioactive dose? (1459 answers, 23% correct)

December 2, 2013Why Do Ants Have Two Stomachs? (1451 answers, 58% correct)

February 2, 2015Can science settle the riddle of the chicken and the egg? (1451 answers, 19% correct)

April 22, 2013While you’re sleeping your brain can... (1449 answers, 44% correct)

April 27, 2015What purpose does a fever serve? (1449 answers, 87% correct)

July 31, 2017Which of the following things can crows do? (1448 answers, 32% correct)

September 3, 2012How does sunscreen work? (1446 answers, 0% correct)

May 26, 2014How can you win a game of paper-rock-scissors? (1444 answers, 56% correct)

December 14, 2015If we ever build a Star Wars lightsaber, what would be its biggest problem? (1444 answers, 30% correct)

January 18, 2016Which of these factors is the most important in assessing avalanche risk? (1444 answers, 61% correct)

September 13, 2010Is there life on Mars ? (1443 answers, 51% correct)

February 3, 2014How long was a diplodocus’ day? (1441 answers, 46% correct)

January 8, 2018According to a recent study, the number of earthquakes in 2018 may increase owing to: (1436 answers, 11% correct)

June 26, 2011What is the probability that among 57 invitees to a party, two will have the same birthday? (1434 answers, 25% correct)

September 26, 2016If you looked inside a butterfly cocoon, you would find... (1431 answers, 38% correct)

May 19, 2014Why is fish fat recommended in our diet for health reasons? (1410 answers, 40% correct)

October 24, 2016Which of these plays a key role in cloud formation? (1409 answers, 49% correct)

August 13, 2012What’s the best way to keep cool in the desert? (1408 answers, 95% correct)

January 20, 2014Why doesn’t a giraffe get dizzy when lowering its head? (1406 answers, 15% correct)

November 11, 2013Why are the largest waves ever surfed in Nazaré, Portugal? Because of: (1403 answers, 59% correct)

April 10, 2012You want to watch a DVD that’s been lying around for number of years. How long is it guaranteed to last? (1395 answers, 64% correct)

December 28, 2015Army ants build bridges using their bodies to cross gaps. Where do they build them? (1391 answers, 36% correct)

June 24, 2013The chemical composition of tears: (1388 answers, 39% correct)

March 9, 2015Why does a tuning fork have two tines? (1385 answers, 29% correct)

April 29, 2013How many notes can you play on an alphorn? (1361 answers, 54% correct)

June 25, 2012Boomerangs come back because (1355 answers, 66% correct)

January 25, 2016Why are submarines demagnetized? (1355 answers, 62% correct)

November 18, 2013How many constellations are there in the zodiac? (1351 answers, 31% correct)

May 13, 2013What differentiates the plant kingdom from the animal kingdom? (1345 answers, 55% correct)

September 16, 2013Mint is refreshing because the menthol it contains: (1345 answers, 50% correct)

June 10, 2013Why do so many tornadoes occur in the flat Great Plains states in the US? (1343 answers, 61% correct)

January 31, 2012There are fewer left-handed people because: (1338 answers, 16% correct)

May 6, 2013Half, or nearly half, of our DNA is: (1337 answers, 53% correct)

June 18, 2012Our internal biological clocks are regulated primarily by: (1335 answers, 67% correct)

August 31, 2015The mass of our planet (and its atmosphere) is: (1331 answers, 35% correct)

February 23, 2015What causes the characteristic smell when it starts to rain? (1330 answers, 60% correct)

May 7, 2012Airplane contrails have an important influence on: (1327 answers, 46% correct)

March 16, 2017What crops can we now grow on Mars? (1324 answers, 75% correct)

May 20, 2013Many satellites orbit the earth at an altitude of 36,000 km because... (1317 answers, 64% correct)

March 19, 2012Bursting into bloom: how do plants tell time? (1314 answers, 51% correct)

April 14, 2014Why do salty foods cause thirst? (1312 answers, 71% correct)

March 23, 2015Why do certain birds fly in a V formation when they’re migrating? (1310 answers, 67% correct)

June 22, 2015European eels are born... (1300 answers, 30% correct)

April 23, 2012When and where will you absolutely never see a rainbow after a storm? (1299 answers, 47% correct)

May 1, 2017What do horses, rabbits and rats have in common? (1298 answers, 47% correct)

June 19, 2017Where do camels store water? (1298 answers, 13% correct)

February 9, 2015Why do orange growers spray their fruits with water in the winter? (1290 answers, 42% correct)

March 24, 2014You can be sure your egg whites won’t beat up into nice white peaks if you: (1289 answers, 58% correct)

June 20, 2016The archerfish can… (1280 answers, 16% correct)

March 17, 2014What provokes a bee to sting? (1275 answers, 26% correct)

May 30, 2016Ice ages are mainly the result of: (1272 answers, 52% correct)

September 25, 2017What factor influences an orchid’s fragrance? (1271 answers, 33% correct)

August 6, 2018To create replicas of precious metal objects, museums... (1268 answers, 53% correct)

April 1, 2013The Sunflower Follows the Path of the Sun... (1260 answers, 25% correct)

March 3, 2014Which of these phonemes is used by every human language to signify the same thing? (1258 answers, 32% correct)

October 25, 2010Water freezes (1255 answers, 36% correct)

October 7, 2013Nettles in soup don’t sting because: (1255 answers, 43% correct)

June 4, 2018Why do some roses have no smell? (1254 answers, 78% correct)

February 1, 2016After a prolonged period of time in space, astronauts might experience: (1248 answers, 38% correct)

June 11, 2012Which is true? There is more water... (1246 answers, 46% correct)

October 8, 2018Emergency telephones work when there’s no electricity by: (1246 answers, 61% correct)

November 13, 2017Why does airplane food taste so bad? (1242 answers, 61% correct)

October 19, 2015Which type of device consumes the most electricity, proportionally, while in stand-by mode? (1240 answers, 36% correct)

February 10, 2014If you could take out your entire body's DNA, what could you do with it? (1236 answers, 48% correct)

February 29, 2016Why do people with allergies need to be careful about wine? (1229 answers, 41% correct)

April 13, 2015How does the earthworm move around? (1215 answers, 31% correct)

June 16, 2014Is it possible to recognize a liar? (1214 answers, 35% correct)

April 16, 2012Humans need between 7-8 hours of sleep a night because of: (1211 answers, 74% correct)

June 8, 2015Why does water end up forming droplets? (1204 answers, 67% correct)

November 6, 2011How fast does the sense of touch travel, from the skin to the brain? (1202 answers, 49% correct)

November 2, 2015What ‘local’ resource could be used to produce electricity on Mars? (1202 answers, 45% correct)

June 13, 2011127 million years from now, a day will last… (1201 answers, 52% correct)

November 10, 2014If space is a vacuum, then how can rockets propel themselves through it? (1200 answers, 51% correct)

October 20, 2014How did Lake Nyos, in Cameroon, kill 1,700 people? (1199 answers, 48% correct)

May 21, 2012In which environment do tetanus bacteria proliferate? (1198 answers, 25% correct)

June 25, 2018Mint freshens your breath because menthol: (1197 answers, 71% correct)

May 5, 2014By the year 2100, the world’s sandy beaches... (1194 answers, 47% correct)

November 30, 201524,000 years ago, the EPFL campus would have been: (1194 answers, 53% correct)

October 23, 2017In teens, delayed development of the prefrontal cortex causes... (1194 answers, 40% correct)

December 5, 2011It’s hard to kill a fly because: (1186 answers, 29% correct)

September 11, 2017Carrots can improve your eyesight if: (1186 answers, 74% correct)

May 23, 2016Three-toed sloths come down from their tree once a week in order to: (1185 answers, 22% correct)

January 23, 2012Do clouds move at the same speed as the wind? (1183 answers, 42% correct)

July 15, 2013What causes the production of large hailstones? (1177 answers, 42% correct)

April 20, 2015The giant tortoise of Galapagos is endangered because of … (1164 answers, 28% correct)

August 27, 2012Why do we notice more shooting stars in August than in the wintertime? (1159 answers, 21% correct)

December 9, 2013Which pair could create a photovoltaic cell? (1158 answers, 29% correct)

December 12, 2011Why are there holes in “Swiss” cheese? (1150 answers, 70% correct)

September 24, 2012The first day of fall doesn’t always fall on the same date, because of: (1148 answers, 37% correct)

February 20, 2017Why do we find screams so alarming? (1148 answers, 64% correct)

October 29, 2018Do people really see red when they’re angry? (1148 answers, 21% correct)

April 18, 2016What is the most common cause of cork taint in wines? (1144 answers, 13% correct)

August 6, 2012What is the best way to not get stuck when driving in soft terrain? (1143 answers, 62% correct)

May 8, 2017Do fish drink water? (1141 answers, 64% correct)

November 4, 2013Lake Geneva’s salinity has increased mostly because of: (1140 answers, 56% correct)

October 5, 2015Why do sheep often imitate each other? (1138 answers, 51% correct)

August 20, 2012What makes pearls shine? (1136 answers, 65% correct)

June 3, 2013Why do our thumbs have only two phalanges? (1136 answers, 41% correct)

March 10, 2014What was the Sahara like 6,000 years ago? (1136 answers, 47% correct)

April 8, 2013Global warming has caused fishes to get smaller because… (1130 answers, 49% correct)

February 7, 2011The shortest route between Lausanne and San Francisco is: (1124 answers, 67% correct)

January 31, 2011Is it colder at high altitude because: (1115 answers, 56% correct)

November 23, 2015Actual invisibility cloaks could be useful for: (1111 answers, 32% correct)

May 2, 2011When you’re taking a shower, the curtain sticks to you because (1103 answers, 54% correct)

April 11, 2011Why does sound travel faster in water than in air? (1102 answers, 76% correct)

April 21, 2014Mars’ uniform red color is among others due to… (1091 answers, 14% correct)

February 8, 2016Why don’t identical twins have identical fingerprints? (1088 answers, 27% correct)

October 26, 2015To meet all of Switzerland’s electricity needs using only solar power, what would have to be covered with solar panels? (1085 answers, 28% correct)

September 1, 2014International Space Station Astronauts will finally get to drink a cup of coffee. But… (1084 answers, 79% correct)

February 28, 2011A meteorite falling to Earth leaves a crater if it is (1083 answers, 32% correct)

February 15, 2016In a windstorm, what type of trees hold out longest before breaking? (1083 answers, 12% correct)

June 15, 2015If we lived on one of the moons of Pluto, we’d … (1081 answers, 33% correct)

March 7, 2016Why are astronomers convinced there’s a 9th planet in our solar system? (1078 answers, 74% correct)

November 16, 2015Synthetic diesel fuel can be manufactured from … (1075 answers, 27% correct)

December 12, 2016Why is nausea common among pregnant women? (1075 answers, 49% correct)

March 19, 2018Does swatting at a mosquito make it stop trying to bite you? (1071 answers, 19% correct)

December 19, 2011Will boiling water always burn you? (1070 answers, 37% correct)

July 23, 2012Why do some birds of prey attack from the side? (1068 answers, 46% correct)

October 30, 2011Why is the Earth round? (1066 answers, 39% correct)

March 27, 2017The Hura crepitans is a tree that... (1064 answers, 61% correct)

December 7, 2015Large mammals produce tiny spermatozoids, because (1063 answers, 38% correct)

November 21, 2016Which two astronomical events create a supermoon? (1063 answers, 41% correct)

January 17, 2011What does it take to set off an avalanche? (1060 answers, 64% correct)

February 14, 2011The success of a ski jump depends on: (1058 answers, 0% correct)

May 30, 2011What causes traffic jams? (1058 answers, 65% correct)

September 17, 2018The Galleria mellonella moth is exceptional for many reasons, including: (1057 answers, 51% correct)

February 27, 2018Which is one of the main functions of saliva? (1055 answers, 38% correct)

February 13, 2017Frogs are remarkably fast and efficient at catching prey with their tongue. What’s their secret? (1053 answers, 34% correct)

January 10, 2011No two snowflakes are alike because of : (1042 answers, 52% correct)

August 14, 2017What causes muscle soreness after exercising? (1042 answers, 33% correct)

May 16, 2011A feather falls at the same speed as a pebble... (1041 answers, 47% correct)

May 23, 2011Is rainwater potable? (1039 answers, 49% correct)

June 28, 2016Soccer: What do goalkeepers look at right before a penalty kick to predict the direction of the ball? (1038 answers, 62% correct)

October 17, 2011Hot chili peppers burn your tongue because: (1032 answers, 36% correct)

February 6, 2017What gives soap its cleaning power? (1029 answers, 72% correct)

November 28, 2016What factor has the most influence on the level of the oceans? (1023 answers, 40% correct)

February 19, 2018How does baking soda get rid of bad smells? (1023 answers, 58% correct)

April 7, 2014In a battle between veiled chameleons, which one has the best chance of winning? (1017 answers, 46% correct)

December 20, 2010 The Earth closer to the Sun: (1016 answers, 36% correct)

May 28, 2018How did the Vikings navigate their ships while sailing? (1014 answers, 33% correct)

March 14, 2011What limits the height of skyscrapers? (1013 answers, 35% correct)

December 16, 2013Where do most of the comets that we can see from Earth originate? (1011 answers, 50% correct)

September 26, 2011A piece of chewing gum will completely deteriorate (1009 answers, 36% correct)

December 13, 2010A winter tire is different because of: (1007 answers, 39% correct)

April 25, 2016What causes cats to shed in the springtime? (997 answers, 41% correct)

June 18, 2018 A spider’s silk thread is proportionally: (995 answers, 93% correct)

May 12, 2014Scientists have predicted an El Niño for 2014 based on: (992 answers, 72% correct)

November 20, 2011Where is the world’s oldest nuclear reactor? (991 answers, 35% correct)

May 16, 2016If sound could travel through space, what kind of noise would the sun make? (991 answers, 19% correct)

May 22, 2017Why does your urine smell bad after eating asparagus? (986 answers, 73% correct)

May 9, 2016Beneath 750 meters of ice in the Antarctic, scientists have found: (979 answers, 50% correct)

March 21, 2011Why does the moon appear larger when it’s low on the horizon? (977 answers, 47% correct)

April 4, 2011Snakes don’t have legs because: (977 answers, 53% correct)

May 29, 2017What do tiger shark embryos eat? (977 answers, 29% correct)

October 9, 2017Why do some odors disappear when they come into contact with stainless steel? (972 answers, 24% correct)

January 24, 2011Why does our thumb only have two phalanges? (971 answers, 31% correct)

June 12, 2017Tennis: what's the main difference between a one-handed and a two-handed backhand? (971 answers, 22% correct)

November 12, 2018What’s the most effective thing I can do to reduce my carbon footprint through my diet? (970 answers, 52% correct)

July 9, 2012How do windtowers traditionally used in Middle Eastern architecture cool buildings? (965 answers, 55% correct)

April 18, 2011Can you walk on eggs without breaking them? (964 answers, 66% correct)

March 28, 2011Why does sap rise in the trees in the spring? (963 answers, 49% correct)

October 10, 2011Why does the inside of fridges remain cold? (962 answers, 41% correct)

March 28, 2016Coral bleaching happens when: (961 answers, 40% correct)

September 5, 2016Northern lights are caused by: (959 answers, 70% correct)

April 25, 2011To save 10 minutes on a bus journey, a Swiss traveler have to pay (955 answers, 27% correct)

June 9, 2014Six months per year in the Lake Maracaibo region of Venezuela… (953 answers, 16% correct)

May 25, 2015The octopus has an extremely useful gift for escaping predators: (949 answers, 50% correct)

October 11, 2010Why do we see half a rainbow? (946 answers, 57% correct)

December 23, 2013How do some plants manage to avoid frost damage in the wintertime? (942 answers, 52% correct)

May 11, 2015The Hubble telescope detected a "smiley face" in space. What causes this phenomenon? (940 answers, 57% correct)

March 7, 2011On Earth, anti-matter (937 answers, 45% correct)

June 23, 2014If bumblebees disappeared from our fields and gardens… (934 answers, 49% correct)

March 16, 2015How do we estimate the age of the Earth? (934 answers, 68% correct)

August 24, 2015Whistled languages, which are used by herders in some parts of the world to communicate over large distances, (932 answers, 50% correct)

May 15, 2017Why is the North Pole drifting towards Europe? (929 answers, 29% correct)

September 28, 2015What is distinctive about Drosophila suzukii? (927 answers, 54% correct)

June 26, 2017For long-lasting giant soap bubbles, which factors are the most important for the bubble solution? (920 answers, 42% correct)

December 27, 2010How long does a plastic bottle take to decompose? (909 answers, 49% correct)

November 28, 2011At the Equator, a basin empties... (902 answers, 57% correct)

June 6, 2011Your tongue sticks to a popsicle because (895 answers, 48% correct)

September 19, 2016The age of some species of sea turtle can be determined by: (893 answers, 45% correct)

October 4, 2010A sound wave (887 answers, 0% correct)

April 30, 2018To enhance your creativity, it's best to: (887 answers, 58% correct)

September 27, 2010What’s the best way to memorize lectures? (867 answers, 65% correct)

February 13, 2012Air pockets when flying are caused by: (866 answers, 53% correct)

June 13, 2016It’s impossible for life as we know it to develop in 90% of galaxies because of … (865 answers, 61% correct)

July 30, 2012How do mangroves absorb oxygen in muddy water? (842 answers, 60% correct)

October 24, 2011We use 230 volts current because of (839 answers, 81% correct)

June 20, 2011It takes longer for a plane to fly in one direction than the other because of… (817 answers, 45% correct)

November 13, 2011Where, besides the human, can leprosy be found in Nature? (815 answers, 16% correct)

October 12, 2015Millipedes are good for the soil because they… (803 answers, 41% correct)

December 23, 2011Why is glass see-through? (802 answers, 43% correct)

May 21, 2018Children’s muscles tire less quickly than adults’ because: (799 answers, 57% correct)

June 5, 2017What unorthodox energy source may one day provide lighting at refugee camps? (796 answers, 67% correct)

March 13, 2018Some plant species are rare because they are more vulnerable to: (785 answers, 41% correct)

October 18, 2010Carbon is (783 answers, 0% correct)

November 1, 2010Snow appears to be white, because of: (783 answers, 69% correct)

November 29, 2010The water on Earth originates from (778 answers, 36% correct)

June 6, 2016How do butterflies find their food? (775 answers, 76% correct)

November 11, 2015Geothermal heat is a clean form of energy that comes from: (773 answers, 21% correct)

June 27, 2011What makes jam set? (765 answers, 59% correct)

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March 21, 2016Daylight savings time … (749 answers, 72% correct)

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May 14, 2018Water rolls off lotus leaves because they are covered in: (737 answers, 37% correct)

February 21, 2011A water/cornstarch mixture hardens due to (734 answers, 47% correct)

August 21, 2017Winged ants swarm together in flight because : (733 answers, 59% correct)

November 19, 2018The food industry accounts for what percentage of Switzerland’s environmental footprint? (721 answers, 52% correct)

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October 30, 2017If half of the Milky Way galaxy were filled with intelligent extraterrestrial signals, we would intercept: (652 answers, 54% correct)

November 22, 2010Which soil retains the most carbon? (630 answers, 64% correct)

November 20, 2017The fly amanita mushroom is poisonous because: (624 answers, 27% correct)

December 4, 2017If fruit flies are exposed to the cold when they are young: (624 answers, 50% correct)

November 15, 2010According to Moore’s law, microprochips: (608 answers, 68% correct)

November 8, 2010Endogenous retroviruses are viruses: (603 answers, 78% correct)

October 16, 2017Why are female tilapia fish smaller than males? (596 answers, 41% correct)

November 6, 2018A recent study has shown that old trees in a forest: (591 answers, 47% correct)

April 24, 2017The blob is an amazing, giant single-cell organism that: (584 answers, 49% correct)

December 6, 2010Twitter limits the size of messages to (566 answers, 45% correct)

May 7, 2018What did researchers discover about bees after fitting them with RFID tags? (467 answers, 54% correct)

February 4, 2019Which of the following can change your perception of how food tastes? (332 answers, 44% correct)

December 24, 2018Why is Rudolph the Reindeer’s nose red? (27 answers, 63% correct)

May 9, 2011Une plume tombe aussi vite qu’un caillou... (0 answers, % correct)

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