Category: Science and Tech

Half Toroidal Vortex in the Swimming Pool

By Anupum Pant

Have you ever tried dragging a plate (the one you use to eat food) on the surface of a swimming pool? If you haven’t, you’re missing out on something really cool.

Dragging a plate across the surface of a pool creates a toroidal vortex in the water which, thanks to the combined play of friction and pressure, keeps it going for a long time and long distance. Dolphins, volcanoes and human smokers all do it. It’s a perfect way to create disturbances in fluids  which can travel relatively long distances – the whole length of a pool in this case. A vortex travels slow usually in the perpendicular direction of its plane and could take several minutes to traverse, say the length of a pool. But, if done right, it won’t die out easily.

Another interesting thing to note in the plate and pool experiment is that there are two vortices created, each at one end of the plate. Both of them  travel together and seem to be rotating in opposite directions. So what really are these?

This is how it works.

Think of it as a curved tornado, a semi circular one created across the whole semicircular part of the plate which is inside the water. Here’s a creative way to see this half toroidal vortex in action.

Largest Rock Ever Moved

By Anupum Pant

The story of the largest rock ever moved by man goes back to the year 1768 – A time when even ball bearings weren’t around. It’s hard to believe that no one has topped it after that. Not even after immense technological advancement of the twenty first century has man moved a rock larger than that one.

In 1768, in order to build a huge statue for Peter the great, a three million pound stone was required to be moved into St. Petersburg. This would later serve as a platform to put up the equestrian statue on it. But before everything, a rock that huge needed to be found. An award was announced for anyone who could do that. The perfect rock was thus found when a peasant claimed he knew where it was. The problem was it was 8 miles away from where it needed to be. No one had moved anything so huge before. Still, Catherine the great, not knowing if her order would get fulfilled, ordered it to be moved.

Someone had an idea of how to do it. This is what the proposal said. Cut a tree trunk into half hollow both the parts from the inside and place brass balls inside and close it like a sandwich. Now the upper slice of the trunk could slide with minimal effort. Several suck contraptions were made and the stone was moved on these. Ball bearings were being use before anyone even had an idea that ball bearings were something that needed invention.

via [Futility Closet]

Wood Turned to Stone

By Anupum Pant

For a whole semester I had not noticed a huge 5500 pound log in front of one of the buildings at college which I used to pass by everyday. Probably because trees are everywhere and to prevent me from getting overwhelmed with excess information, my subconscious chose to filter it out. Today, while parking my bike I did chose to give it a conscious look. There was a board by the log which mentioned what it was and it was clearly something that was worth displaying.

petrified woodThis thing I was looking at was a petrified wood specimen. Yes, a piece of wood that turned into rock several million years ago. It was 220 million years old. Elated, I posted its picture on my instagram. This is what it looks like.

At first, not knowing how it must have formed, I thought it must be due to high pressures, like diamonds are formed. However after going through some text online I found out that the process by which these things are formed is very different from how gems like diamonds are formed.

Very specific conditions need to be met in order for a wood to turn into stone. It starts with a piece or a stump of dead tree getting engulfed with sediments or something else. This prevents it from coming in contact with the atmospheric oxygen. The cut off oxygen supply delays the decomposition of this log. So, now the log would take centuries before it is decomposed. It remains intact inside.

Now, if the wood comes in contact with mineral rich water or volcanic as (in ways that doesn’t burn the wood), the water starts soaking into it and starts replacing the organic matter with minerals. The whole log’s cell and fibre structure is preserved because all of this takes place at a microscopic scale. Over millions of years these minerals like silica crystallize and forms the petrified wood. The rate at which this whole process occurs is not very well known.

326346_1348795063If there’s just silica, they aren’t usually coloured. But if it gets infused with other element rich minerals like copper, cobalt, manganese etc, these woods can end up getting lined with beautiful colours. Other times silica can crystallize in different form an create an opal inside a wood. These make rare and beautiful gems like this one. [more pictures]

Due to the crystals that are formed in it, these usually break with clean cuts and give it an appearance like the wood stem was cut using a chainsaw.

Petrified wood is not too rare. Often, you can find them strewn over rock formations. I would very much like to stumble over one some time. I still consider it precious because it’s millions of years of history sealed in wood. But then that can be said about every stone you come across. This however is something that happens when very special conditions come together.

Sometimes whole forests get petrified and among these some trees can remain standing. In such cases a standing petrified stump is a beauty to watch. Here’s a 15 million year old standing petrified wood caught on video.

Researchers have made instant petrified wood in laboratories too. For this, a few material scientists from Pacific Northwest National Laboratory cut a cube of wood and gave it an acid and silica bath a couple of times, air dried it and then cooked it for 2 hours in an argon filled furnace at 1400 degrees Celsius. [Link]

Petrified wood is often cut into little pieces, polished and used in lapidary work, or to make jewellery. Tabletops are made out of slabs cut out of huge logs.

[Ref 1] [Ref 2] [Ref 3]

How Long can a Straw be?

By Anupum Pant

Vat19, a fun online store, sells this set of DIY connectible straws which can be used to make the most elaborate straw contraptions to wither mix two drinks in real-time or something else. Of course the better thing you could do with them is get two sets or more of these straws. But how long can you go before your straw no longer works?

Well, horizontally you could make it as long as you want it. Also, on some other planet you could make extremely long vertical straws too. But here on earth, there’s a limit to the longest vertical straw you can make. You can make a longer one indeed, but it won’t work.

~10.3 meters is the theoretical limit – that’s for perfect vacuum.  That’s pretty long. Still, humans can’t make perfect vacuum using their mouths, so practically even a 6 meter long straw would make you sweat hard. Also, the inner diameter of the tube matters too. Why? Veritasium explains the physics behind it…

Massive Amounts of Gold in the Sea

By Anupum Pant

We’ve been mining gold for about 6000 years now. It isn’t totally clear how much has been mined yet. Still, there are a few reliable estimates which say that about 150,000 to 170,000 tonnes of gold has been mined till date. The 170,000 tonnes figure is the most reliable estimate, which would mean that the amount of gold ever mined can fit in a not-so-massive cube with each side measuring 21 meters. However, some estimates take the figure up to 2.5 million tonnes.

That said, how much more is yet to be mined then? A good estimate is that about 52000 tonnes of gold is still out there that can be realistically mined. But is that all?

No. 52000 tonnes of left over gold might be economically viable, but there are places here on earth which hold massive amounts of gold. It is in the oceans. No, not in treasure chests of sunken pirate ships.

In the ocean waters there’s about 20 million tonnes of gold waiting to get harvested. Although there isn’t a good method by which this can be extracted, it sure is a massive amount of gold. The gold is so spread out in the waters that you’d have to process billions of litres of water to find one gram of gold. The concentration is in the orders of parts per trillion. No one knows how to extract that.

Now, that’s the gold dissolved in water. There’s also gold trapped in the sea bed, just like we have it here on land, in rocks. Even that is 4-5 kilometres under the sea. And it’s trapped in rock there. So, no one has a good way to extract that too.

via [Oceanservice]

Coffee Powered Engine

By Anupum Pant

Well, this is not really coffee powered, rather heat-from-coffee-powered. This is a Stirling engine. An engine like any other heat engine which converts heat into mechanical energy. For a Stirling engine to work, all you need is a relatively tiny amount of temperature difference on its two sides.

The lower part of the engine setup can be heated using the heat from a coffee cup, and the upper part is exposed to the room temperate. As the lower part of it gets heated, the air expands, pushes the piston. Next, it cools, the air contracts and the piston comes back. This translation is converted to a circular motion in this specific setup. Sixty symbols explains…

Indoor Paper Boomerang in Seconds

By Anupum Pant

Professor  Yutaka Nishiyama, a mathematician from the Osaka University of Economics has devised a perfect way for you to create your own indoor paper boomerang. No longer would you have to get those relatively heavy wooden ones and find a huge open place to try and get them to return.

All you have to do is to download the appropriate PDF from his page here, print it out on a B4 paper and follow the instructions. If done right, you’ll have some thing that would go around in a 3-4 meter circle and come back to you. All of  it indoors! Playing with it, you’d be doing something like this…

At first it looks like it would be tough to make it work. But trust me, it’s too easy to get it right.

via [FutilityCloset]

National Radio Quiet Zone

By Anupum Pant

541px-National_Radio_Quiet_Zone.svgThis 13,000 square miles of rectangular land, somewhere in the US, is the national radio quiet zone – or NRQZ.

Some of it falls in Virginia and the other major part of it is west Virginia. A tiny part of Maryland (on the top) is also included.

Living in the NRQZ means that the people who choose to live there have to sign a contract saying that they’ll never own some of the modern equipments like wi-fi, microwave, a wireless telephone etc. People living there are banned from using almost anything that uses electricity and could possibly cause a radio interference. That is because the rectangular NRQZ is home to one of the largest radio telescopes at the  National Radio Astronomy Observatory (NRAO) at Green Bank, west Virginia.

Any wireless transmitters in this very interesting piece of land spanning about 10 miles in all directions of the radio telescope has a potential to cause an interference. It’s like the 50s in here. No cellphones there. Life’s pretty different and it’s for the good of scientists from all over the world who wish to use this world-class piece of technology. This small film talks about it…

via [the Atlantic]

Cellphones and Cancer

By Anupum Pant

WHO classifies cellphones as devices that could possibly cause cancer. But, then it says the same about coffee and pickled vegetables. The whole world has come to believe that cellphone radiations do cause cancer – a gross interpretation of WHO’s statement. It says that it is a “possible carcinogen”. WHO, or no one else for that matter knows for sure that there is a clear link between cellphones and cancer. In fact, the evidence also tilts on the side that says there’s no clear link.

Clearly, the number of people using cellphones exploded in the last couple of years. However, the number of people reporting brain tumour – which they say is caused by cellphone radiation – has shown no spikes in recent years. If that isn’t convincing enough…

The radiation from a cellphone is more or less the same as the radiation that comes from several other devices like your wi-fi router or bluetooth. It is a non-ionising radiation. That means it is nothing similar to X-rays or cosmic rays – non-ionising radiation doesn’t damage your DNA. Or, no clear link has been established yet that says so.

Healthcare triage makes some really convincing points about the same. So the good news is, you don’t have to throw away your cellphone.

What if the Earth was Flat

By Anupum Pant

Well, the earth clearly isn’t flat for us. Or may be it is. What if someone was travelling at a very high speed towards it, considering relativistic effects, it would be pretty much flat for them. So, it actually could seem flat to someone.

What if it was flat for us too. How would the gravity of such a planet work. Would people really fall off the edge? Or would they have a hard time reaching the edge. Here’s an in-depth analysis of it with Michael Stevens from Vsauce.

Maternal Dermatophagy – Skin Eating Kids

By Anupum Pant

Firstly, these are amphibians. Not reptiles, nor are they worms or anything else. The young ones of these strange animals are even more stranger. For 100 million years, the young ones of these creatures have adopted a bizarre practice of eating their own mothers – eat their skin, actually.

The weird practice also has a name and is called der­matophagy, which translates to “skin-eating” in Greek. Or, Maternal dermatophagy, in this case where the mother’s skin is being eaten.

The most interesting part is that this actually works out well for these creatures. In fact the young ones also come with specialized set of teeth to accomplish this. The mother starts developing a nutritious fatty layer on her skin after laying eggs. So, the young ones come out hungry, use their specialized teeth to peel her skin off and eat it to start the development process.

[Read More]

100 Billion Frames Per Second

By Anupum Pant

Couple of months back there were researchers unveiling the trillion frames per second camera, which actually didn’t capture real-time image. This time it is different.

Researchers from Washington University say they’ve built a camera that can capture 100 billion frames per second. It is faster than anything ever made and works on a completely different principle – which they call the compressed ultrafast photography (CUP).

This camera is so fast that it can capture a light photon in motion. Here’s a slow motion video of light bouncing off a mirror. The amount of time taken for this event to happen spanned only 300 trillionth of a second.

via [ScienceAlert]

The Long Face Syndrome

By Anupum Pant

Mouth breathing is the root cause of several other problems. Worsening of sinus blockages is probably the best known among them all. Besides that when you are not breathing through your nose, you are not giving a chance for the air to move through your mucous membrane which produces nitric oxide in the body – Lack of which is a bad news for your heart and blood vessels. And the list goes on.

But the other unusual and lesser known problem associated with mouth breathing is this. It can make you look uglier! Which as the name suggests, is an ugly facial feature – long and narrow face. And then, if their tonsils swell due to this, their jaws start to adjust into a weird position in order to gather the maximum amount of oxygen into their bodies. This happens mostly to kids when they start breathing through their mouth early in life. However, it isn’t only limited to kids. Also, it’s easier to fix this on kids.

So, if your kids uses his/her mouth to breathe, it is a very good idea to correct it right away.

Kids who end up being chronic mouth-breathers are likely to have something called the long face syndrome.

via [Link]

Birds to the Moon

By Anupum Pant

A few species of bird seem to disappear during the winter and this is something which has made people think in the past. Charles Morton was one of those people who pondered about it and came up with a theory. According to his paper (birds in the moon) published in the year 1703, birds go for a vacation to the moon during winters. Yes, he estimated the moon was 200,000 miles away and said that the birds were able to complete this feat within 60 days. [more]

One thing he wasn’t wrong about was the amount birds travel. Arctic tern for instance is the bird that covers the maximum distance during migration. They literally fly from the Arctic to the Antarctic, and back in a single year. In one year they travel about 50,000 miles. Considering the amount they fly, it proves to be a good form of exercise for them.

Aristotle believed that a kind of bird changed into some other type during winters. Others thought they grew on trees and blossomed only during spring.

But that obviously isn’t true. This is where they actually go and how they do it…