Author: Anupum Pant

Dancing Drops of Water and Dipping Hands in Molten Metal

By Anupum Pant

When you sprinkle water on a hot pan, you’ll find that the droplets start dancing on the surface, as if there was no friction at all. From far, this effect looks a lot like water droplets on a lotus leaf (a super-hydrophobic surface). But, the physics behind this phenomenon is completely different. Read on to find out what is the mystery behind these dancing drops of water.

The Leidenfrost Effect

Why does this happen?
Unlike the drops on a lotus leaf, this happens at a particular temperature for a specific liquid. Different kinds of liquids display this effect at different temperatures.
For water, at a temperature when a small amount of water in contact with the pan gets heated enough to form a thin-film of vapor below the drop, water is no longer stuck on the pan (water sticks to some surfaces due to low surface tension). The drop has a thin vapor film below it which enables the drop to move around on the film. The formation of this vapor film is a continuous process, till the whole drop turns into water, one film at a time. This is called the Leidenfrost Effect.

Some liquids like liquid Nitrogen are extremely cold. At normal room temperature, they start boiling. A normal room’s floor is like a hot pan for liquid Nitrogen. So, it forms these dancing drops on a floor which is just at room temperature. You can try this yourself – If you can find some liquid Nitrogen, you can simply drop it on the floor and watch droplets moving effortlessly. They won’t stop moving!

Dipping hands in Liquid Nitrogen

The temperature of liquid Nitrogen is around -195 degree centigrade. It is one of the coldest substances and is used with extreme caution in industries and laboratories. If it touches you, your skin can easily get burnt. Yes, burnt – at extremely low temperature. It could probably also make the dipped limb useless for life. So, you shouldn’t try stuff with liquid Nitrogen at home.

But, it turns out, you can safely dip your hand in it for a small amount of time and return unharmed. Thanks to the Leidenfrost effect. Our hot-pan like hand – for cold liquid Nitrogen – makes a thin film of vaporized Nitrogen around the whole hand. This film, protects our skin from the ill effects of extremely cold temperatures. Still, there is no reason for you to try this. It has been done already.

The crazy duo from Myth Busters tried this with molten lead. It worked!  They, of course had to wet the finger with water – for the vapor film formation.

Water flowing uphill

Recently, an undergraduate research student group from the University of Bath found out a way to manipulate the movement of water on a specially designed surface, using this phenomenon. They found that machining ridges on the surface (and heating it) would make the thin vapor films under water droplets move in such a way, that they could use it to propel drops against gravity. They were able to demonstrate this by showing water moving uphill on a slope. It is enthralling to see it for yourself. I’ve attached their video below.

Sharks Are Not So Bad After All

By Anupum Pant

Sharks have been on earth for millions of years more than we have been here. Also, they haven’t changed much since a long time. The kind of sharks we see today, were the same sharks that existed 350 million years ago.

That means, modern sharks have lived happily for millions of years without eating humans. Even today, they aren’t very keen on killing us for food. They simply aren’t designed (or haven’t evolved) to do that. Humans were never a part of their normal diet. Instead, they normally feed on small fish. While a few other species of sharks may eat seals, sea lions and other mammals too. In fact, they can go on for months without food.

Funny as it may sound, sharks are scared of humans. When a shark sees a human in water, it gets confused and scared. It goes near to check,  and this usually results in an accidental bite. They don’t kill humans out of aggression. With 15 rows of razor sharp teeth on each jaw, even their gentle bites may kill a person. About only 20 out of 300 species of sharks are reported to have been involved in accidents with human beings.  About 100 such accidents occur every year.

Not being insensitive about human deaths: Can you estimate how many people do sharks kill every year? The answer is 10. Ten people, on an average are killed by shark bites every year. That is about 1/15 th of number of people killed by coconuts every year*
*Note: “150 people are killed by coconuts every year”, is a popular urban legend. The coconut death figure is a crude estimate or just a figure pulled out of thin air.

Nevertheless, the number of people killed by sharks every year is very very less (again, even a single human death isn’t really ‘less’). I’d rather not use statistics to prove my point. [image]

Why are sharks scared of us? … Why shouldn’t they be?
We kill about 100 million sharks every year. That is such a huge number when compared to number of people sharks kill every year. Again, statistics could be deceiving here. But we do get an idea. There is a massive difference in the number.
Why? Humans catch sharks for their meat, internal organs and skin,  to make products such as shark fin soup, lubricants, and leather etc. Some times, fins are cut and live sharks are thrown back into the sea, crippled. This eventually kills them due to excessive bleeding or other obvious reasons.

It is ironically that we move into their natural habitat and in turn blame sharks for destroying our boats, surf boards. Moreover, we are shocked to hear about reports of shark attacks on humans. Shouldn’t it be the other way round? We should stop looking at sharks as if they are the monsters; we are. At the same time, that doesn’t mean you should risk your life by going in shark waters to give it a high-five.

Random Science Fact:  

Only 14% of the Earth’s species are known to us. 75% of all the species on Earth will be gone within the next 300 years. Think about those species which will go extinct while we are here, and we’ll never know about them.

Elephant Bird – The Heaviest Bird Ever

By Anupum Pant

Scientific Name: Aepyornis maximus

No, it isn’t about a bird with a trunk or tusks. Weighing almost half a ton, the aptly named, elephant bird of Madagascar, was the heaviest bird to have ever existed on earth.  It looked like an Ostrich on steroids and of course it was a flightless bird. The number 3 bird in this picture is an illustration of the Elephant bird (around 10 feet in height) [image]

Note: Although we say that it was the heaviest bird to have ever existed, we can only say that because we haven’t been able to find any traces of a larger bird yet.

Interestingly, it wasn’t something that belonged to the Dinosaur era. It went extinct recently, around the 17th or 18th century, probably due to humans hunting it for food. Since cameras did not exist at that time, only written accounts of its sighting have been found.

As logic dictates, a huge bird would lay huge eggs. So, with a volume of about 180 to 250 times that of a chicken egg, measuring about 1 feet in height, its eggs were the largest laid eggs ever; larger than human heads. The shells could hold around 11 liters of liquid. Its eggs were said to have fed whole families. Some of them have been preserved – Some are being auctioned and some are available in museums. National Geographic Society in Washington holds a specimen that has the skeleton of an unborn Elephant bird.

 

Klein Bottle – A Bottle That Contains Itself

By Anupum Pant

To appreciate the beauty of mathematics and nature there is no escaping without learning about a Klein Bottle. A three-dimensional representation of a Klein bottle looks like this – [image]

There are number of phrases you can use to describe (not exhaustively) it. A few of them are as follows:

  • An object with no boundaries.
  • An object with no inside or outside.
  • One sided surface.
  • Non-orientable surface

Wikipedia describes it as:

The Klein bottle is a non-orientable surface; informally, it is a surface in which notions of left and right cannot be consistently defined.

Simplifying things: A Möbius strip is a simpler example of a non-orientable object. That means it has no inside or outside. Add another aspect – having no boundaries – to it, it gets more complex and you end up with a Klein bottle.
If you haven’t heard of Möbius strips, to understand such surfaces, you can make one for yourself now.

  1. Tear off a strip of paper.
  2. Hold it horizontally, straight with both of the short edges in your hands.
  3. Now, twist one of the edges by 180 degrees and join the two short edges. You’ll have something like this in your hands – [image]

Test the surface and edges: On this object you just created, move your finger along the surface. You’ll find that your finger comes  back to the same place eventually. There is no inside or outside for this object, there is just one surface.
The same thing happens with its edge (try moving your finger along the edge). Here is a Music box playing a Harry Potter theme continuous – forward, inverted, forward and so on – manner; Relevant video: [video]

Now spin it (the Möbius Strip) fast. You can NOT practically do it. I mean, spinning it like you spin a circle and get a sphere. There! You have a Klein bottle. It is better than a Möbius strip in a way that it (Klein Bottle) has no boundaries.

Klein bottles cannot actually exist in our three-dimensional worlds, the ones that look like them (Klein Bottles) are just 3D representations of a 4D object. Like a two-dimensional drawing of a 3D cube. These models are available for you to buy. Interestingly, in spite of having no inside or outside, they can be filled with a liquid. But, given the opposing force of air, they are pretty tough to fill. It is important to note that the 3D representation of a 4D Klein bottle has an intersection of material, this doesn’t happen in 4D. It is like the intersecting edges of a 3D cube in the 2D representation.

You’re thinking 3D? At MIT (and other places) 4D printing is already happening.

If you are having a tough time imagining this 4D object, the following 4D animation might help (or leave you perplexed) – [video]
[Extra reading for math geeks] as if they already didn’t know about Klein bottles.

Axolotl – A Walking Fish That can Regenerate Limbs

By Anupum Pant

If you are looking at an Axolotl for the first time, it will confuse you. With an oddly shaped body that resembles both a catfish and a salamander, you’ll wonder if it lives in water or on land. [Image]

What is it?

A fish? Axolotl, commonly known as the Mexican Walking Fish, isn’t actually a fish. It is an amphibian, which means it has both lungs and gills. They almost never come out of water, hold their breath and take in oxygen using their gills (those three pairs of parts coming out at the back of its head are the gills). They can hold their breath for a year, beat that Mr. David Blaine.

Or Salamanders? They are closely related to salamanders and interestingly the adult Axolotls look like baby Salamanders. They have long abandoned the usual amphibian-transformation from a larva stage to an adult. Unlike Salamanders, they don’t transform into adults that can live outside water. They stay in water and walk around on the water-bed.

However, strange species of Axolotl was once delivered to a zoologist Auguste Duméril, which had somehow transformed like salamanders and would happily come out of water. But this transformation (metamorphosis) shortened their life span. Later it was found that this process can be artificially triggered by injecting iodine. (Do NOT try this at home)

As pets: Today, these animals are fairly common and are used as exotic pets all around the world. Especially in Japan, people love to have them in their aquariums.

Side note: Like several other Pokémon based on real animals, Whooper and Mudkip were actually based on Axolotls.

Regenerative Powers

Besides having the ability to walk underwater and its unusual appearance, there is something that is much more interesting about them. Unlike, almost any other vertebrate, they have the power to regenerate various cells. Not just cells, Axolotls can regenerate complete body parts – limbs, gills, eyes, kidneys, even large portions of its liver and its heart muscle. Even portions of its spine and brain can be regenerated. They are able to grow back a severed limb in span of few months. This is the reason scientists love these creatures and conduct a number of studies on them every year.

Gravity Light – A Light With No Running Costs

By Anupum Pant

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A $5 lamp that lights up using gravity can be used without electricity or batteries, over and over again with no running costs. Impressive enough? There is more.

A British company, after working for 4 years on this project, with an aim to replace kerosene lamps, started an internet fundraising campaign on Indiegogo and successfully raised about 7 times more than what they had aimed for – aimed for raising a fund of $55,000 and ended up raising $399,590. They had invented the Gravity Light.

Gravity light uses the force of gravity to light up – a free, completely reliable and totally unlimited source of energy. For it to start, the user is supposed to lift up a hanging weight of about 10 kg. And there! As the bag full of dirt, stones or sand starts coming down slowly, it lights up an LED light. The weight keeps coming down for about 30 minutes and then it has to be raised again. It generated a very minuscule amount of electricity and manages to give out a much brighter light than a kerosene lamp.

The energy generated from it can also be used to charge batteries, charge phones, run a radios etc, with attached accessories.

Interestingly, the company has plans to develop various other gravity powered solutions. So, in the future, we might probably see a way to reach the internet without batteries or electricity.

Other interesting lighting ideas:

[Gravia lamp] [Water + Bleach lamp] [Algae + CO2 lamp]

 

Hot Ice

By Anupum Pant

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For years we’ve been subconsciously conditioned to think of something cool when the word ‘ice’ is heard. But, does ice always has to be cool? How much more interesting, than water-ice, can ice be?

What is it?

The name: Hot ice isn’t solidified water, it isn’t anything even close to water. Neither is hot ice, hot. It is just a common name for Sodium Acetate Trihydrate. At room temperature, this substance looks like ice crystals and if heated, it starts turning into a transparent liquid. Since, the ice like crystals are formed at a relatively hotter temperature than water-ice, it is called hot ice.

Everything freezes. While metals ‘freeze’ at extremely high temperatures and carbon dioxide freezes at extremely low temperature, Sodium acetate freezes at 54 degrees centigrade. But, that is hardly anything interesting about it. There is more.

Touch water and turn it to ice

Think about water: Cooling water, beyond its freezing point without it getting solidified, can be done and it is called ‘super-cooling‘. This can be done by not letting water (distilled water) find any ‘nucleation points’ or simply by using an extremely clean tray to freeze it. Now, water remains in a liquid state despite being cooled under 0 degree centigrade. At such a state, if water is disturbed, say using your finger, a chain reaction starts and the water freezes almost instantly. But, doing it is tough.

Making hot ice at home – The same thing that happens with super-cooled water, can happen with sodium acetate. Touch the liquid sodium acetate and it magically turns to ice, it is indeed a fascinating process to watch (watch in the video below). And can be done fairly easily. Moreover, you are not at a danger of getting poisoned in any way. This is the reason it is used to make hot ice. It can be made at home using vinegar, baking soda and a steel vessel.

Ben Franklin Effect – Influencing People

By Anupum Pant

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Influencing people

Named after Benjamin Franklin, who observed this effect, the Ben Franklin effect is a lesser known yet interesting Psychological finding that can be used to influence people. According to it:

  1. If we do someone a favor then we tend to like them more. (read till the end for an example of a practical application)
  2. The reverse of this effect is also true – If we harm someone, we are more willing to harm them again as a result.

In the words of Benjamin Franklin:

“He that has once done you a kindness will be more ready to do you another than he whom you yourself have obliged.”

Side note: I love biographies. I love them because, there you have an access to a treasure of life-long experiences of great people. I feel, it is like collecting XP (experience) points in a Pokémon game. The more you manage to collect, the better you do in life. And biographies are one of the most efficient sources for XP.

While going through Ben’s autobiography a few months back, I found a lot of his observations to be extremely interesting and I had noted this down in my notes.

How he used his observation

He was able to befriend a rival legislator by trying this out. The following is an excerpt from his biography:

Having heard that he had in his library a certain very scarce and curious book, I wrote a note to him, expressing my desire of perusing that book, and requesting he would do me the favour of lending it to me for a few days. He sent it immediately, and I return’d it in about a week with another note, expressing strongly my sense of the favour. When we next met in the House, he spoke to me (which he had never done before), and with great civility; and he ever after manifested a readiness to serve me on all occasions, so that we became great friends, and our friendship continued to his death.

Jecker & Lendy published a study in the year 1969 which used 3 groups of students to prove this scientifically. In the study, the students from the first group liked a professor more than the other two groups. It was to this group the professor had asked for a favor.

How can you use it?

  1. If you want someone to like you (or influence someone), even though it may seem counter-intuitive, you could just ask him/her for a favor.
  2. If some random stranger asks you for a favor, you could be a little more cautious about you liking him/her.
  3. To get a better effect, ask a person who is tired.

No wonder, guys after fetching a 100 chocolate ice-cream cups for their girl-friends, only tend to fall more in love with them.

Prince Rupert’s Drop – Exploding Glass

By Anupum Pant

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What is it?

At first, a Prince Rupert’s Drop is an interesting yet harmless looking drop of glass with a long tail. It looks like a tadpole: [image]

It is no different from an annoyed person who refuses to let out his resentment – A slightest something might make him explode suddenly, but it isn’t easy to make him let it out. Confused? Read on…

Now, think of a glass drop that has immense amounts of potential energy stored inside it – It explodes (actually implodes) when the tail is disturbed, but it is impossible to hit it hard with a hammer and break it.

How?

A Prince Rupert’s Drop is formed when a drop of molten glass is suddenly dropped into a water bath. This quick cooling, solidifies the surface fast, while the inner part remains molten. Now, glass formed on the surface, being a poor conductor of heat doesn’t allow the inner part to cool quickly. When the inner part starts cooling, it tries to shrink and pulls the surface towards it. As a result, great amount of potential energy gets stored inside, in the form of stresses (stresses are seen using a polarized filter). This stored energy gets released when the tail is disturbed – It explodes into very tiny pieces of glass.

Toughened glass – a stronger variety of glass used in several places – also uses a similar technique to make strengthened glass.

On Wikipedia, a user asked about the possibility of utilizing the energy released from this explosion, being used to fire a bullet from a barrel. An interesting possibility, I must say.

The Name

Prince Rupert of Rhine did not discover the drops, but played a role in bringing them to Britain. He gave them to King Charles II, who in turn delivered them to the Royal Society for scientific study. Prince Rupert’s Drop was a widely known phenomenon among the educated during the 17th century – far more than now.

Watch it being explained better

Probably the best demonstration of this glass drop exploding is right here on the internet. Couple of months back, a YouTuber, Destin (Channel: SmarterEveryDay) posted a video demonstrating the physics behind it. He recorded  the progression of the explosive fracture using a hi-speed camera (at more than 100,000 frames per second) and calculated the speed of the fracture travelling through its tail (~ 1.5 miles per second). I’ve attached it below for you to watch.

Yakhchal – An Ancient Cold Storage Marvel

By Anupum Pant

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During a period when electricity was only a thing for the Gods, around 400 B.C.E., in the hot-arid deserts of Iran where temperatures touched 40 degree centigrade, ancient engineers had found a way to keep their ice from melting. Two thousand years back, a cold storage facility was being used. The impressive thing about it – it was clean and sustainable technology.

What are these?

Yakhchals, or ice pits of ancient Persia were the huge mounds (buildings hollow from the inside), which made it possible for Persians to store away the ice for summers, meat, dairy products, other food items and chilled frozen Faloodeh for the palace. Beside treats for the palace, the method of preserving ice was so professional yet simple that even the poor could afford it.

Structure and Working

The structure of these buildings above the ground is a large mud brick dome, often rising to about 60 feet in height. Below it are large underground empty spaces, up to 5000 cubic meter in volume. This space had access to wind catch and often contained a system of wind-catchers that could easily bring temperatures inside the space down to frigid levels in summer days. The structures were built so well that many still remain standing.

Working: The massive insulation built into the walls (due to the use of a special mixture of sand, clay, egg whites, lime, goat hair, and ash) and the continuous cooling waters that spiralled down its side kept the ice frozen throughout the summer by evaporative cooling (just like those mist fans). They also had a trench at the bottom to catch water from the molten ice and to refreeze it during the cold desert nights. The ice was then broken up and moved to rooms deep in the ground. As more water ran into the trench the process was repeated.

Geography: These were built in the areas that had suitable condition for producing natural ice or places where there was feasibility of water freezing during the cold nights.

Major architectural elements: 

  • Shading wall – To avoid direct exposure to sunlight and to let the structure remain cool in the shade.
  • Provisional pool – To supply water for evaporative cooling to take place.
  • and Ice reservoir – To keep the cycle going. Freeze > Melt > Refreeze at night and so on…

The end of Yakhchal (reasons)

  • Since the advent of electricity-guzzling freezers and air conditioners, unfortunately, the use of these architectural wonders has been considered as foolishness. This is probably the reason no Yakhchals are being used for cold storage anymore.
  • Desert storms, caused a lot of erosion to these structures, especially to the ones that were isolated in the desert regions.
  • Since Yakhchal’s ice formed in the open it was prone to combining with dust and resulted in contamination. That was another reason it wasn’t considered as a choice useful enough for modern purposes.

Hit the like button if you learnt something from this article.

Gallium Metal Melts in Your Hands

By Anupum Pant

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Atomic number: 31
Symbol: Ga

At first what seems like an uninteresting material, Gallium, in truth has, much more to it than meets the eye.

Gallium’s melting point

Like most other metals, Gallium is solid at room temperature (or liquid if it is too hot in your room). But, if it is held [in hands] for long enough, it melts in your hands, and doesn’t poison you like Mercury would. This is because of its unusually low melting point of (~29 degree Centigrade). It can melt by drawing heat from a human body which is normally at around 37 degrees.

Buy Gallium: This property, and the affordable price of $24 for 15 grams, probably makes it an appropriate gift for science geeks. They will love making mirrors at home by sticking it onto plain glass sheets.

Talking about a classic prank, it is advised to beware of the scientists who would offer spoons made out of Gallium to unsuspecting guests at a tea party. These spoons melt in hot tea and make it a potentially harmful concoction to ingest.

Since it isn’t poisonous like Mercury, Gallium is often mixed with Indium to further lower its melting point to -19 degrees. This makes it a safer option for us to use in thermometers instead of Mercury.

Interesting uses and compounds

  • Dilute sulphuric acid changes the surface properties of Gallium due to the formation of Gallium Sulfide on the surface. It no longer sticks that badly to glass, gets pulled up into a ball and starts beating like a heart when dichromate is added.
  • 98% of the world’s Gallium metal is used as Gallium Arsenide and Gallium Nitride, used in the electronic industry for making semiconductors, LEDs and high-speed circuits. In fact the laser in your Blu-Ray player is also made using Gallium.
  • Probably the most amount of Gallium used in a single place is at a Neutrino observatory in Russia. It houses around 57 tons of liquid Gallium.
  • With Silicon, Graphite and Molybdenum, Gallium is also used in ski wax to make skis more slippery.
  • Finally, nothing beats a metal that melts in your hands.

Tardigrades – Toughest Creatures on Earth

By Anupum Pant

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So, if you think elephants or cockroaches are tough, that could be because you probably haven’t heard about these amazing creatures called Tardigrades (picture).

What are Tardigrades?

Tardigrades, also known as moss piglets or waterbears, are oddly cute little animals that live in water and feed on moss. Their size ranges from 0.1 mm to 1.5 mm and they have eight legs (they walk like bears). The most extreme thing about these extremophiles is that they can survive almost anything (actually, they kind of die for a while with an option to come back to life later). Here is a list of things Tardigrades can survive. They can:

  • Survive without water and food for 10 years.
  • Waddle away in the vacuüm of space (for 10 days & get exposed UV radiation), come back and walk around as if nothing happened.
  • Survive 1000 times more radiation that would kill an elephant.
  • Live through extremely low temperatures (almost absolute zero) or high temperatures (~150 degree Centigrade)
  • Repair their own DNA after getting exposed to lethal amounts of radiation.
  • Survive pressures of about 300 Jumbo jets stacked on a person. (6 times more than the deepest ocean trenches)

Scientists love them

People at NASA and the European Space Agency love doing tests on them because they think, Tardigrades can help them understand the origin of life on earth (probably by supporting Panspermia). Also, scientists want to find out more about their extreme capabilities. If you ask them, if these things are aliens, they’ll tell you – “Probably not”

[Learn more about Tardigrades]

4D Printing is Here

By Anupum Pant

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We had just started getting comfortable with printing objects in 3D, and 4D printing is already here. Early this year, in the month of April, Skylar Tibbits, an architect, designer and computer scientist at MIT, gave a revolutionary demonstration explaining their advances in the field of 4D printing at a TED conference. This was an initial proposal and it got things moving at a rapid pace.

Side note: In the world of 3D printing:

What is 4D printing?

At first 4D printing sounds like a catch phrase, it isn’t really just that. 4D printing is actually 1D better than 3D printing and it aims at making objects out of a 3D printer, that can reconfigure themselves into useful shapes, on their own. For instance, think of a non-living stick changing itself into a 3D cube as time passes. In short, 4D printing will enable us to create living objects without any living cells, micro-processors, chips or batteries involved. Sounds simple enough, but the promises are nothing less than extraordinary.

In the TED talk attached below, Skylar explains how a string of plastic placed in water can turn itself into the letters MIT. But, this was something that happened back in April. Things have moved further.

A few days back, Researchers at the University of Colorado Boulder revealed a successful test of their 4D printing technology. They were able to print out flat objects using normal plastic combined with a smart material which was able to turn into a cube on its own. Cubes are just the start.

According to scientists, in the future, 4D printing will probably churn out smart car bodies that would heal automatically, smart soldier uniforms and advanced building materials. Imagine a camouflage material that changes to match the surroundings, that could be the future. Or a pipe that contracts and expands to move water without pumps. Or a building material that builds itself into a structure. 4D printing could probably best suited for building in an extremely hostile environment like space. The possibilities are endless.

But, let us not get ahead of ourselves. It is almost impossible to predict what we’ll actually see in the future. Things have just started to happen in the field of 4D printing. But, it sure looks amazing. What will you build?

Gomboc – An Object That Never Falls

By Anupum Pant

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There’d be hardly anyone among us who hasn’t played with a roly-poly toy during their childhoods. If you know it by some other name, you could think of it as a toy that never falls, no matter how hard you hit it, and sells in variants which look like this. That isn’t exactly what a Gomboc is, but you get an idea about what it does – It does not fall. For more, read on.

What is a Gomboc?

A Gomboc (Gömböc) is a mathematical 3-D shape which has only one position in which it can stand and is made up of a single material  of uniform density. If you try to make it stand in some other way, or try to knock it down, it moves back to that single stable position, gradually. When placed on its side, it starts rocking magically, gains momentum, straightens itself and gradually comes to rest in that single position. Here is a video of a Gomboc doing its thing.

A Gomboc is an object surrounded by a number of complex curves, it takes an immense amount of accuracy to get the surfaces right. An accuracy of  the orders of around 1/10th of a human hair’s thickness is required for it to work properly. For better, people have started 3D printing these complex shapes.

The world’s largest Gomboc was displayed in China in the year 2010 which measured around 3 meters in all directions.

Terrestrial tortoises, who use a similarly shaped shell to get on their feet when turned upside down, were using it long before humans had found a way to construct it. The first time we made it, was in the year 2006. Evolution got there first!

How is it different than a Roly-Poly toy?
A roly-poly toy usually has an internal counter weight made up of a heavier material. But a Gomboc is made up of a single material.

Uses: Use it as a paper weight or to gift it to your friend who is a math geek. Tortoises use it to save their own lives.

Where can I buy one?
You can get one for yourself from an official website of the inventors – Here.

Longest Continuously Running Experiment – 83 Years and Counting

By Anupum Pant

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An experiment so slow that a professor overseeing it, died without having seen the results for half a century! The Pitch Drop experiment, started by Professor Thomas Parnell of the University of Queensland in the year 1930, is the probably slowest science experiment and also holds the Guinness World Record for the world’s longest continuously running experiment ever.

What is the experiment?

It is an experiment designed to measure the flow of a solid looking piece (image) which is actually an extremely viscous liquid (actually a Viscoelastic Polymer) with a viscosity of approximately 230 billion times that of water. The name used for this class of extremely viscous liquids is, Pitch – Bitumen, Asphalt, Resin and Rosin are a few examples (not Glass). These things are so viscous that you can strike them with a hammer and see them shatter into sharp flakes (like glass), but it flows. The experiment is explained in detail, in the first few minutes of this radio show attached below. (the second half is pretty interesting too, but that is for some other day)

Other unbelievable materials previously covered in this series – Aerogels and Superhydrophobic surfaces.

Side note: The overseer of this experiment, Prof. John Mainstone actually lived through the drops of pitch falling three times, but unfortunately missed watching it happen every time (for 3 times in 50 years). In all, 8 drops have fallen since 1930.

  1. 1979 – He missed it because he wasn’t in the laboratory for the weekend.
  2. 1988 – Missed it because he went out for a tea break.
  3. 2000 – A camera was installed as a precautionary measure, the equipment malfunctioned; missed again!

He recently died waiting to see it in action. Since then, three web cameras have been installed as a fool proof measure to record the extremely rare event. You can watch it happening online here, although you might have to wait for several years to see it happening. (To confirm the live stream, look at that clock in in it and confirm with time here). There is also a time-lapse from 28th April 2012 – 10th April 2013 compressed into a 10-second-long video of the drop forming, embedded below.

A parallel experiment running at Trinity College, Dublin also wasn’t able to capture the rare scientific event on camera in spite of several drops falling since the commissioning of the experiment (1944). Finally, after 70 years of patient wait, on July 11, 2013 it was recorded on camera.