amazing – Awesci – Science Everyday

The Underwater Vacuum Cleaners

By Anupum Pant

If you didn’t know, most white sand you see on some beaches around the world, has at some point in time, passed through a fish called the parrot fish. It’s an amazing ecological role the parrot fish plays.

An interestingly similar ecological role is served by a marine animal with a very leathery skin called the sea cucumber. Professor Ove Hoegh-Guldberg explains why these organisms have such an important role in the marine environment.

Basically, while scavenging for algae or minute aquatic animals, sea cucumbers ingest a lot of sand. As it passes through their bodies, the digestive system increases the pH of the sand, making it more basic. When this comes out, the sand is clean and turned basic. This way it plays a chief role in countering the negative effects of ocean acidification.

It also helps coral reefs survive by supplying them with calcium carbonate (a by product of its digestion process) and helping them maintain a net inflow of calcium carbonate.

The ammonia that comes out also makes the bed more fertile, making it much more suitable for coral reefs to grow.

Watch these underwater vacuum cleaners in action below.

Faking Sleep Affects Performance

By Anupum Pant

A couple of days back I talked about how standing for a few seconds in a superman position could increase your level of confidence and could help you ace interviews. Today it’s time again to look at a technique to increase performance by fooling your body.

First of all, you need to stop thinking you didn’t sleep well today. That is because the mere act of thinking you slept well makes you perform well. It’s been proven.

In a group where everyone got equal sleep, half of the people were just told by “experts” that they had 29% REM sleep (which is better) and the other half were told that they had only 16% REM sleep (that actually decreases performance). The catch was, they all had slept for equal times and everyone would have had more or less equal percentages of REM cycles. Only, they were told wrong things by “experts”.

This word of mouth coming from the “experts” actually affected the performance of these two groups. The group that was told they had a greater percentage of REM sleep performed well. And the group that was told they did sleep as well as the first group didn’t perform as good. I’m assuming both the groups were first informed about how the percentage of REM sleep affects performance.

So, stop cribbing about how tired and sleepy you are.

Galileo’s Paradox

By Anupum Pant

Here’s an image of a contraption. It is basically a long stick hinged at one end and is free to move about the other. At the end of it rests a ball. Near the ball there’s also a cup fastened to the stick. The big stick is lifted up high and is temporarily supported by a small stick.

Now, what do you think would happen when the temporary support is removed? Normally, it would be very intuitive to think that the cup and the ball would fall at the same speed. In other words, nothing fascinating would happen. Both would fall and the ball would roll away…no?

However, something very unexpected happens when the support is removed. Something that, in a jiffy demonstrates some very important concepts of physics like centre of mass, torque and acceleration.

The big wooden stick (with the fastened cup) falls and it falls faster than the ball. Actually it falls and also rotates. As a result of the swing, the cup comes under the ball just before ball reaches it and the ball ends up inside it.

Under the influence of the same gravitational force, irrespective of the mass, the cup and the ball must have fallen at the same rate, as predicted by Galileo? What really happens? The video explains…

Double Pendulum and Why We Can Never Predict Weather

By Anupum Pant

A single weight, if suspended from the ceiling, forms a pendulum – A simple device whose position at any point in the future can be predicted fairly easily if the initial conditions are known.

Now, if another pendulum is attached to the bottom of this first pendulum, preferably using a rod (not a string), and is then given a good amount of initial energy, things move from a simple single pendulum to a very complicated two pendulum system.

The system turns so chaotic that it is impossible to make two of such exactly same systems, forget keeping them synchronised. Even if every mass and ever little distance is carefully calculated and two such systems are constructed, it would be impossible to drop them from the same height and see them move in the exactly same manner.

That is because even if they are really dropped from the same position, they’d in reality have a very tiny difference in some parameter, which would eventually become so huge that the two systems would soon go out of sync. Initially they might really seem like they are moving in a synchronized motion, but that doesn’t stay for too long.

This is also the reason why we’ll never be able to predict the weather perfectly. Nikola explains…

A Scientist’s Way of Making Super-Strong iPhone Cases

By Anupum Pant

Bulk Metallic Glasses (BMGs) A.K.A Amorphous metals, give you the goodness of both metals and glasses. They literally are glasses made out of metal. Unlike the most crystalline metals, BMGs are made by cooling certain liquid metals very quickly to lock the disordered glassy structure in place. They aren’t crystalline like your everyday metals and instead have a structure like that of glasses – disordered.

Some of these BMGs have amazing properties. Like super high hardness, about 3 times the hardness of steel is one of the most alluring properties they have.

They’ve been around since the 60s, and mass producing them has always been tough. Until now, BMGs were never used for something as ordinary as a smartphone case. But the recent innovation in manufacturing coming from a Materials scientist at Yale will probably soon bring to the market these new iPhone covers that’d be 50 times harder than plastic, or 10 times harder than Aluminium, and almost three times the hardness of steel.

A Simple and Elegant Cloaking Device

By Anupum Pant

In the year 2011, UTD NanoTech unveiled their carbon nanotube invisibility cloak, making us move one more step closer to realizing a piece of magical cloth which fictional characters often use to turn themselves invisible. And then there was a 3D printed invisibility cloak too.

A few researchers at the University of Rochester have now created their own elegant version of an invisibility cloak. It’s, in principle, a fairly simple optical device which uses just four lenses to cloak objects behind it, keeping the image behind it still visible.

In fact, whatever it does, it does it in 3 dimensions. That means, the viewer looking through the device can actually pan to change the viewing angle and can still see the image of the background, undistorted, as if there were no lenses in between, in real-time. And it is probably the first ever cloaking device to be able to do that.

The device has a blind spot (sort of). In a way that It doesn’t cloak anything that lies in the axis of the lens system. The cloaking area is in the shape of a dough nut. Any part of the object that accidentally enters the axis area becomes visible and conceals the background. The device is simple and cheap enough to be easily scaled to cover greater area, as long as lenses of that size can be made. The video explains it better.

via [Quarks to Quasars]

Singing Sand Dunes

By Anupum Pant

I cannot say why you’d do it, but suppose you were on a hike to the top of a 120 feet sand dune in the centre of some desert, say near Al-Askharah, a coastal town in Oman. Unfortunately, it’s also the mid summer time, with 50 degree Celsius winds blowing at 50 miles an hour, and the dune you are climbing has a slope of 30 degrees. There’s nothing else (besides sand) to be seen or heard for miles around you.

The numbers are apparently perfect for a very eerie phenomenon to occur. And then the whole desert suddenly cries out a booming chorus of a very low hum (Like someone playing a very low note on the cello). What could have possibly caused that?

For ages such sounds in the midst of empty deserts have been bewildering people. Marco polo mentioned it. Charles Darwin also wrote about the “Bellower” in The Voyage of the Beagle. Moreover, until recently, even modern scientists weren’t sure what caused these sounds. It was only during the year 2009 that things started becoming clear when a group of researchers started experiments with sand on an incline in a laboratory environment.

The low droning hums, now as we know, come from within the sand dunes. The Sand particles are blown by the wind, causing an avalanche. As the sand falls across the 30 degree incline of the dune, they vibrate, synchronise and send the vibrations into the dune. The dunes pick up these tiny synchronised vibrations and amplify them, causing the low droning hum; coherent enough to resemble musical notes.

This only happens at few places around the world. In Morocco the dunes cry out an echoing hum of 105 hertz. Whereas in Oman the sands create a mixture of frequencies ranging from low 90 to slightly less low, 150 hertz. Something similar is also heard in the death valley. The video explains…

Gravity Explained

By Anupum Pant

I’m always amazed by how teachers all around the world come up with fantastic ideas to make science easier for kids. A couple of months back we saw a video of Dan Burns using a trampoline to explain the space-time warping at a Physics Teacher SOS workshop in Los Gatos High School. In fact there is even a place on the web where you can learn it to do yourself [here].

Another explanation which came around much later just takes the cake. EdwardCurrent uses a “space-time stretcher” to demonstrate how gravity, well, stretches the space-time fabric. Moreover, the material he uses to construct this teaching aid comes mostly amongst all the old stuff lying in his garage.

Continue reading Gravity Explained

Shot Towers

By Anupum Pant

The way of making lead musket balls before 1782 involved a lengthy process. And if you had a huge army, then you were in for a massive task. To make each ball:

A chunk of lead was melted in a crucible
Poured into a mould
It was let to stand to solidify
The mould was broken
Final finishing of each ball was done
and each ball was checked for roundness by rolling it on an inclined plane

Then everything changed in the year 1782, when a plumber from Bristol William Watts, got this seemingly simple idea – Drop molten lead from a long tower and let the surface tension do the work.

He got this idea by observing raindrops, which formed perfect spheres while they were free-falling. Before telling anyone about it, he tried implementing his idea. He dropped molten lead into a bath of water from the tower of his local church. It worked perfectly.

He did a couple of other experiments at home and finally patented his idea by the end of the same year. It wasn’t long until shot towers started sprouting all over the world. William made a good fortune out of this.

A shot tower is a long hollow building, like a light house, which has the machinery to melt lead at the top point. The molten lead is dropped into the long hollow shaft through sieves, and the bottom part of the building has a bath of water to catch lead balls. The free falling lead turns into a sphere due to surface tension and solidifies in air due to flowing air. After shots are made, they are lifted from the water and checked for roundness by making them roll on an inclined plane. Defective ones are sent back to the top.

The tallest shot tower ever built was 263 meters long and was constructed in the year 1882. It still stands in the Melbourne suburb of Clifton Hill in Australia. There are several others around the world which are still standing. While many others have either been destroyed by men or nature.

via [PSSA]

Cotard Syndrome – Walking Dead Disorder

By Anupum Pant

Neurological conditions can be bizarre. Now I know that there is a condition that can delude patients to such an extent that they start thinking they no longer exist, or are dead. It’s called the Cotard Syndrome or the walking dead disorder.

Named after a French doctor Jules Cotard, the Cotard syndrome is a neurological condition in which severe degeneration of neural synapses occurs and messes with the facial recognition and emotion centres of the brain. Their brain creates a totally impaired perception of the self. As a result, patients suffering from it some times get convinced that their body parts no longer exist, or have started decaying.

Often times, patients think that they no longer need to eat (because they are already dead), and they starve to death.

There have also been cases in which patients have tried to get rid of their body parts using acid because they felt doing this was only the way to free themselves of being zombies.

Graham, a person who got caught up by this bizarre disorder was totally convinced that his brain did not exist. He had lost all his senses, he thought he was in a state between life and death, and saw no point in continuing to live this way. He tried to kill himself by getting electrocuted in a bathtub. Graham got cured to some extent, but the disorder completely messed up the rest of his life.

Another person who suffered brain injury due to a motorcycle accident was first cleared as health by doctors initially. After which he went on a vacation to South Africa. By the time he came back, he was totally convinced that he had died and had gone to hell.

Thankfully, it is an extremely rare disorder.

via [NewScientist]

Sea Glass – Is It Trash or What?

By Anupum Pant

In the Glass Beach, a beach in MacKerricher State Park near Fort Bragg, California, like the name tells you, you’d normally find too many glass pieces on the beach. These glass pieces that people often find in beaches like these, aren’t exactly those sharp shards of glass that are sharp enough to harm you. Rather they are physically and chemically weathered pieces of glass – round and small.

This type of glass is called sea glass and has been a fancy of those hobbyists who like collecting these pieces to make beautiful adornments.

This kind of glass, often found on some beaches usually starts as shards of broken glass from dump or other such sources. In about a span of 1-2 years, the tumbling and weathering makes these pieces smooth and rounded. And then they are collectively known as “genuine sea glass”

At this particular beach in California, the beach glass that has formed over the years, first started coming in when residents who lived close to the beach started dumping garbage into the beach. Local clean up services tried to clean up the mess, but most of it had already gone in for natural weathering by that time.

Soon after the clean-up services came around, the beach became a great place for hobbyists to collect these naturally weathered beautiful glass pieces. All the trash that was first thought to be a mess, now became a tourist attraction – Naturally weathered genuine sea glass was a thing of natural beauty now. And then this smuggling of sea glass by tourists had to stop. First the mess had to stop, now the mess being taken away by tourists had to stop.

And once the glass has started to go away, now there is a move to replace all the glass – that was once considered garbage!

[Read more]

Screaming Coin and a Singing Spoon

By Anupum Pant

Dry ice, or Cardice – as British researchers call it, is a solid form of carbon dioxide. When carbon dioxide is cooled below temperatures of -78.5 degrees centigrade, the gas gets directly frozen into a solid form. -78.5 degrees centigrade is extremely cold, and handling dry ice without proper protection can be very dangerous – could cause frostbite / burns. The point being, it’s extremely cold.

Since it’s too cold compared to something at room temperature, even everyday objects at room temperature can make it vaporize. A simple metal coin at room temperature would feel like a hot pan to dry ice. So, when a coin is shoved into a piece of dry ice, it creates a funny sound, just like water would, on a very hot pan; or, you could say the sound be very much like a hot metal ball being dropped into a cold bath of water (the temperature difference being much less in this case, of course).

This is how it works: The metal piece at room temperature vaporizes some amount of carbon dioxide from the piece of dry ice when it comes in contact. There’s a pressure difference (Bernoulli’s principle) associated with this process and the gas tries to escape. This makes the metal vibrate very fast, creating that funny sound. This is how it sounds…

Metals work best because they have a good thermal conductivity. For the sake of trying it out yourself, if you have a piece of dry ice lying unused, you could dip a spoon in hot water and make it touch the piece of dry ice. A slightly warmer spoon will probably give you a better effect. And then the spoon will be singing…

Best Explanation of Quantum Entanglement

By Anupum Pant

I don’t know a lot about Quantum entanglement, but I still think it is very interesting. So much that a PC game which contained of this concept, immediately landed on the list of my most favourite games. Yet, it sure is a tough thing to get into your head.

Fear not. Associate Professor Andrea Morello of University of New South Wales (UNSW) is here to explain it to you, in this video which people have started calling – “The best explanation of quantum entanglement so far”. I have to admit it, I am still not sure if I really understand what the professor tries to explain in the best explanation ever video.

In very simple words entanglement works like this. If two objects are entangled with each other, and if you separate them by any distance (even place them at the opposite ends of the universe), then they’d still remain connected very peculiarly. Entangled particles even separated by a massive distance would still be connected – as in, whatever you did to one of the particles would instantly happen to the other particle at the other end.

The instantaneous reflection of changes done on the first particle to the other particle happened faster than light. And Einstein didn’t like that, he called it “spooky action at a distance”. Tom me, this video explains it better…

Mike The Headless Chicken

By Anupum Pant

Mike, a Wyandotte rooster, born in the month of April (year 1945), was an average male chicken living an average chicken life at some barnyard in Fruita, Colorado. On September 10th 1945 this changed. The rooster was no longer a normal male chicken of some random barnyard. It was making news.

The second world war had ended and families no longer were required to cut down their consumption of meat. So, a farmer’s wife, Clara Olsen decided to treat her family with a nice meal after the numerous sacrifices made in the second world war. She asked her husband, Lloyd A. Olsen to chase down mike and kill Mike for the night’s meal.

Lloyd did exactly that. He took aim and cut off Mike’s head. Normally, like all the chickens make erratic movements after getting cut, Mike with no head on his body started running, spewing blood around too.

Unlike all the chickens who spurt out blood and no longer have enough of it to remain alive, Mike’s bleeding stopped after a while and he stood up. Now Mike was a headless chicken moving around the barnyard. With no eyes, or even a head for that matter, mike started walking around and running into objects.

Soon, Mike adapted to this situation and started living a normal life. Except, he was a chicken without a head. Mike went on to live for 18 months, sustaining on food and liquids that were dropped using a dropper into the hole in his neck. Mike sure had the will to live.

Mike was a celebrity now. Life magazine published a piece on him. People from all over the country came around, just to have a look at a live headless animal walking around like nothing had happened.

Mike, Mike, where is your head.
Even without it, you are not dead!

Was the song little girls then started singing while playing around at school

Confused, the farmer took Mike to the University of Utah to get him checked by researchers. It was found that the brain stem at the top of his neck didn’t get cut. He still had the part which controlled his motor functions, and that was, more or less, enough for a chicken to lead a headless life. Basically, just enough to move around and continue normal body functions – like to digest food and respond to stimuli.

Even today, Mike has a festival named after him – Mike The Headless Chicken Festival – which is Fruita’s highlight during the year.

via [RoadsideAmerica]

The Birthday Paradox

By Anupum Pant

Imagine you meet a random person in the street and ask him/her when is their birthday, there’s a huge chance that the person’s birthday will not be the same as your birthday. In fact, the probability of both your birthdays being on the same day is around 0.27%. Fat chance. At the back of our heads, this is something that is very clear to all of us.

Again, if you repeat this by asking about 22 people the same question, the chance of you finding someone having the same birthday as yours is still around 5%. Too less. This is too is a very intuitive piece of information.

But consider this. If I put all of the 22 guys and you in a room, there’s a big chance that 2 people in that room will have the same birthday – a 50% chance. Moreover, if there are 70 people in the room, this chance increases to about 99.99%. This is called the birthday problem or the birthday paradox.

So, what changed when 20 people went into the room? It was just the fact that in the room, we are picking 2 people from a group of 23 people. That is equivalent to this – everyone is asking everyone their birth dates. Everyone doing it simultaneously makes the probability much higher. The probability of two people sharing a birth date among a group of 23 people is far higher than you alone going around and asking all the 22 people, and finding someone having the same birthday as your’s.

Suppose there are 200 people in the room. The probability of 2 people sharing their birthday is massive (and yet not definite). There is in fact a 99.9999999999999999999999999998% chance!

Finally, if you had 367 people in a room, at least a pair among these 367 people in the room would definitely have the same birth date. The 99.99% chance shoots up to a definite (100%) probability if there are 367 people in the same room. Think about it for a minute.