Dark side of the moon!!!

When we look at the moon in the night sky, all the time we only see one side of the moon. We on Earth  never get to see the far side or the dark side of the moon! Ever thought why?

Well… Let’s see why? the Moon makes one revolution around the Earth about every 29 days, and that’s what causes the Moon phases. But the Moon also rotates once every 29 days also. Because of this, the same side of the Moon always faces the Earth. This is because of something called tidal locking.

Tidal force is like, When you are standing up, Gravity acts on you. And your feet are just a little bit closer to the center of the Earth than your head, this means that the Earth pulls with a slightly larger gravitational force on the lower half of you than the upper half. This slight difference is called a tidal force.

When something like a Moon is close enough to a planet, these gravitational tidal forces cause the Moon to spin at the same rate that it revolves around the planet. When this happens, we call it tidal locking, and that’s why we always see the same side of the Moon!

If you want to know, how tides are formed on ocean, read this What really cause tides?Also, do you know that the far side of the moon doesn’t have the dark spots like on the near side of the moon? Find out why on my next article..

 

Machines that never stop!! Perpetual motion machines?

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Ever heard of a machine which never stops! Well… Technically it’s called Perpetual motion machine. Even if we manage to create one and set it going, it would keep on going until the Big Freeze. Big Freeze is theoretically the end of everything. It’s not set to happen for another 100 trillion years or so.  If that’s a perpetual motion, then it should run for atleast that time!!! Now, you know what to say when someone says, they have built a perpetual motion machine!!

But let’s see the origin story of these perpetual motion machines. The most common of these, and the oldest, is the overbalanced wheel. In a typical version, flexible arms are attached to the outer rim of a vertically mounted wheel. An inclined trough is arranged to transfer rolling weights from folded arms on one side of the wheel to fully extended arms on the other. The implicit assumption is that the weights exert more downward force at the ends of extended arms than is required to raise them on the other side, where they are kept closer to the axis of rotation by the folding of the arms.

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One of many perpetual motion machines are continuous motion that would supposedly be possible if hindrances like mechanical friction and electrical resistivity could be eliminated. But these are not those science problems where they give “IDEAL” objects.

Some part of those forces can be minimized but they can never be completely eliminated without spending additional energy. For instance superconductive metals, whose electrical resistance disappears completely at low temperature. Unfortunately, the energy required to maintain the low temperature exceeds the work that results from the superconductive flow.

There are a lot of machines like these, though there aren’t perfect perpetual motion machines, yet they are super cool to look at them. Some of them are:

Self-winding clock:  It dirives energy from changes in the temperature or pressure of the atmosphere. It depends upon the energy delivered to the Earth by the Sun and is not, therefore, a perpetual-motion machine.

Perpetual energy generator: Of course they don’t completely fulfill our requirement, yet that’s a very good idea..

 

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With water:

 52d42698952d20a7ce2b10c784ca64d4_machine_1316_866Boyle'sSelfFlowingFlask

Magnetic perpetual motion machines: They are a bunch of these around. Using and playing with the attraction and repulsion properties of magnets makes it even cooler..

magpm

I have a question for you, I have come across this image on the internet;);)… My question is, does it work? And if yes, how?

WxPl4

With all this, we can conclude that, for now actual perpetual motion machines can’t be build… And please do answer the question above;);)

 

RFID! Is that the future of barcodes?

These days we see barcodes everywhere. Almost every product has a unique barcode, which contains all the information about the product. 1D barcodes can only hold a maximum of 85 characters and 2d  Barcodes can store over 7,000 characters. With 2D barcodes even complex information like expiration dates and serial numbers can be seen easily.

Before we get into RFID, let’s see how does a barcode and a barcode scanners work? 

If you look at a barcode, you can’t just make a wild guess on where one number ends and another one begins. Each digit in the product number is given the same amount of horizontal space: exactly 7 units. Then, to represent any of the numbers from zero to nine, we simply color those seven units with a different pattern of black and white stripes. So, in order to denote each number, there is a certain combination of white and black for each number from 0-9. The combination for each number is shown in the image below.

barcodestripes

So, how the scanner knows to read these? When light reflects back off barcode into a light-detecting electronic component called a photoelectric cell. White areas of the barcode reflect most light; black areas reflect least. The cell generates a pattern of on-off pulses that correspond to the black and white stripes.

RFID(Radio frequency identification): 

In barcodes, scanner could only scan one barcode at a time, but in RFID, a bunch of tags can be scanned at a time even from longer distances (up to 100 meters in some cases). RFID tags can be used in many places hotels, aeroplains, railways etc… With this technology in operation, you can just walk out of the grocery store with your products through the RFID scanner and without even waiting in a long billing line, get your total bill and payment done.

How RFID works?

A RFID has a tag or label and a reader. Tags are embedded with a transmitter and a receiver. The RFID component on the tags consists of a microchip that stores and processes information, and an antenna to receive and transmit a signal. The tag contains the specific serial number for one specific object.

To read the information encoded on a tag, a two-way radio transmitter-receiver called an interrogator or reader, emits a signal to the tag using an antenna. The tag responds with the information written in its memory bank. The interrogator will then transmit the information.

A passive RFID tag will use the interrogator’s radio wave energy to relay its stored information back to the interrogator.

A batter powered RFID tag is embedded with a small battery that powers the relay of information.

So, definetely it might be the future of barcodes…

Fun fact-  If a smartphone is inside an aluminum foil, covered with aluminum foil, it can’t be detected by any RFID scanner even your phone can’t recieve any calls.

 

 

Antimatter?

For every type of matter particle, there is a corresponding antimatter particle. Antiparticles look and behave just like their corresponding matter particles, except they have opposite charges.

Antimatter particles are created in ultra high-speed collisions. In the first moments after the Big Bang (learn more about it in my previous article Origin of our universe), only energy existed. As the universe cooled and expanded, particles of both matter and antimatter were produced in equal amounts. And the biggest question for which we have no answer yet is, why there is more matter than antimatter in the universe??

For instance, a proton is electrically positive whereas an antiproton is electrically negative and gravity affects matter and antimatter the same way, because gravity is not a charged property and a matter particle has the same mass as its antiparticle

In 1928, British physicist Paul Dirac came up with an equation that combined quantum theory and special relativity ( learn more about it here Special relativity), just a simple one x2=4, this equation can have two possible solutions (x=-2 or x=2), one for an electron with negative energy, and one for an electron with positive energy.

HOW CAN WE USE ANITIMATTER?

The most interesting and even frustrating fact about antimatter is, when matter and antimatter come into contact, they disappear producing energy (annihilate is the technical term for it). This led scientists to think of antimatter-powered spacecraft for more efficient space exploration. Of course that costs billions of dollars though..

Now, the frustrating part is, it is damn tough to contain antimatter because all our equipment is made of matter and as we try to put them in any of those containers, they disappear leaving back some energy. But scientist have managed to contain some antimatter for about 15 minutes, sufficient for scientific study.

So, do you have any clue about having more matter than antimatter?

Wanna know what dark matter is? visit Dark matter.

 

 

What is “BIG” data?

Before we get into “Big data”, let’s see what actually data is. Data is a value assigned to a thing. For example, assume a chocolate. For a chocolate to be unique, there are a few specifications(data) like colour, cost, type, small candy or a big chocolate. Each specification above is a data, but individual data is purely meaningless by itself.

When all those data is combined, we get meaningful “information”. This is something brief about Data. Now, let’s see what Big data is.

Previously only companies used to enter data into the computers, but now with the internet, even users (we) POST or enter huge data, it is estimated that we produce 2 quintillion (which means 1 followed by 18 zeros) bytes of data every day.

How?? For example through facebook or twitter or for that matter any social networking  website the data is given, when we signup or enter our data or post photos or even tweet makes it a data. This is kinda huge data, from just companies entering data to users entering data. Now, we even have machines entering data on a daily basis, like entering the weather information, traffic info, even satellites etc… This huge amount of data is called BIG DATA.

Big data is very useful in various fields, for example, if all the traffic data is accurately taken and processed everyday and everywhere or atleast for a confined place, then it is easy to build a self driving car with all the “traffic” awareness;) Even useful for INTERNET OF THINGS(Internet of things ) This is just a flick on how big data can be used.

Processing is nothing but getting information from the data right! So, how do we process that huge millions of bytes of data?

Well, in those old days, we used to give the data to the computers to process. But now with the tremendous amount of data, we are bringing multiple processors to the data. If you have ever seen server rooms containing data, each server contains processor to process the data.

Quick thought: Some tasks that humans find easy are still difficult for computers;)

Image from Google…

Iris Scan vs Retina Scan…

With the introduction of Iris scan on a smartphone by Samsung, Iris scan has become more popular now. On a smartphone, initially we had no locks then we had password, later on finger-print scanners. Now, to reach the higher level of security we have IRIS scanner on a smartphone.

There is still a subtle confusion among people between iris scan and retina scan. So, let’s see the difference.

Retina: it’s the thin layer that is on the inner back of the eye. The thing is even identical twins do not share the same pattern of retina. However the retina patterns can be changed in case of diabetes or degenerative disorders of the retina.

How a retina scan works?? A retinal scan is performed by sending out an unobserved low-energy infrared light beam into a person’s eye as they look into the scanning device. This beam of light traces the systematized path of the retina. As the blood vessels of the retina are more light absorbent than the rest of the eye, the amount of reflected light varies during scanning. The result received is the pattern of those variations. And that received pattern is the unique identity or life saver or atleast information saver;)

Retina scan requires a very close encounter with the scanning device, that might be one the reasons why a retina scan is not preferred on smartphones.

Iris scan: Unlike retina, iris is flat, ring-shaped tissue behind the cornea of the eye.  The color of the iris defines the eye color.

How an Iris scanner works?? Iris recognition uses video camera with infrared illumination (NIR) on the smartphone or any iris scanner to capture images of the structures of the iris.The images are turned into digital templates and stored. These templates provide a mathematical representation of the iris. It represents a unique identity.

Iris texture always remains extremely stable, doesn’t change at all, because it is internal and protected.Moreover Iris scan can be done from a distance, that is one of the reasons why an iris scan is being used on smartphones.

 

 

Computer Part-2. Processors!! What does i3,i5,i7 mean?

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Part-1 (Computer part-1) of computer was all about, how a computer takes in info.. In this part-2 of computer let’s see what a processor does and how to choose a processor!! This is still an arguable and ground breaking issue …

processor is commonly referred to as the CPU. It can process computer instructions per second measured in hertz. So, it is important to check the clock speed… Like 2 GHz, 2.5 GHz etc..

When it comes to processors, it might be of any company Intel or AMD, the specifications we need to look at, are the same. Few important specs are: number of cores,  32 bit or 64 bit, Cache.. Let’s see each of them,

 

Number of cores (multi-core) 

We are so much familiar with the words single core, dual core, quad core etc.. Dual core has two single cores and quad core has four single cores. In simple words a single core is like one calculator, a dual core has two calculators.

This does’n mean that a 2 GHz dual core is equal to a 4 GHz single core in performance. All this means is that you have two 2 GHz cores working for you instead of one. This is so important to understand the difference, most people confuse here in selecting.

As it goes above, dual core has two calculators and single core has one calculator, if we give an instruction, suppose a mathematical calculation, we can use only one calculator at a time. Having two calculators or having dual core doesn’t make our job any faster in this case. Same is the case with dual core.. Then what is the use in getting dual core or even quad core?? It is so simple answer, when we give multiple instructions or in this case two mathematical calculations. Then each mathematical calculation uses one calculator, with this the two tasks will be completed in very less time..

So, number of cores is equal to number of calculators.. In order to make use of all the cores present there is something called “multi-threading.” A program that’s multi-threaded – written for more than one core – can take advantage of a multi-core processor, even for only one operation by dividing  it among the cores. Multi-cores benefit isn’t necessarily one of speed, but one of smoothness.

It’s so important to know that the extra cores may go to waste. More than that, more cores means more power draw and with that more heat. In a notebook, these become serious considerations.

32 bit or 64 bit? How to choose?

 

Every  hardware component in a laptop requires what’s called an “address” and it is normally be occupied by memory. Your computer knows everything in it by its address, and everything uses memory addresses. So if you only have 4 GB worth of addresses, all the other parts are going to start eating into that, leaving part of the 4 GB of physical memory you have untouched. This is why when you put 4 GB of memory into a Windows XP or Windows Vista 32-bit machine, Windows doesn’t give you the full 4 GB – it may give you as little as 2.5 GB or as much as 3.5 GB, depending on the hardware you have in your machine.

What a 64-bit processor and 64-bit operating system does is dramatically raise the amount of memory your computer can address. By increasing this limit, it allows the computer to see the full 4 GB and still have room for everything else. Still, the move to 64-bit, provided you’re running at least 4 GB of memory can generally be beneficial.

Cache:

 

Cache is basically a memory, or RAM, that’s been built into the processor. if cache is so much faster than memory (and it is), why bother with memory at all? Why not just integrate all that memory into the processor itself? Because memory is physically huge. Sure, it’s not that big when you look at a processor or a stick of memory, but on a typical processor, the L2 cache takes up roughly half the die. So if as little as 4MB of cache takes up that much space, try to fathom how much space 1GB would need.

So, don’t worry much about Cache

Now, let’s see Intel’s i3, i5, i7 processors!!

As long as you understand the above specifications and what each specification does, you are good to go…

First of all,these terms correspond to processors from the specific brand of Intel.

Before you make a purchase though, you should really think about what you are going to do with you computer.  If you are just using your computer to email, surf the web etc…You will be just as fine with a Core i3.

If you are editing multiple files in Adobe Flash, with virtualization software, playing the newest RPG computer game you may notice the Core i5 to be much more faster. The Core i5 is great.

The Core i7 are the current most expensive and top of the line from the Core series of Intel processors. For most computer users, the i7 is probably much more than they’ll actually need or even think they need.  But, if you want the best of the best that will run your video rendering programs, giant RPG games, and many other higher technical programs, go for i7.

There are still lot more to talk about computer which we would do in the next part!!:)

Deep web and dark web??

Did you access your email or facebook or twitter or used drop-box today? If you did any one of those, then you accessed the deep web. The deep web isn’t some mysterious place, it’s just a collection of users private data. It’s hidden because we don’t want anyone to access our private information through facebook or twitter or data on dropbox.

It was estimated that the deep web is about 95% of all the data available online!!

The dark web is similar to the deep web in the respect that it is hidden from the normal web. However the dark web is not information that is not linked, rather it is purposely hidden. To access the dark web you need to use special tools like Tor or Freenet. These are the only ways to get to this hidden content. Though the deep web makes up 95% of all the internet the dark web only consist of about .03%. But that small section has millions of monthly users. The dark web is usually what people actually mean when they refer to the deep web.

 Deep web and Dark web aren’t same. The deep web is on the internet that has the stuff on the internet that can’t be accessed by our traditional search engines like Google. “Dark Web” on the other hand is a term used to describe areas on the internet accessible only through some softwares like TOR. It is the encrypted network that exists between TOR  servers and their clients. As the dark web is pretty much hidden, it is also used for some illegal things. But i have read that the dark web was created by US Navy for transmitting secured information.

What do you think?

Image- Deep-web

 

BLOGGER RECOGNITION AWARD

Thank you so much Sahana from “Jazz lily” for nominating me for this Blogger Recognition award. She is a very talented writer. And her blog is really good. Go ahead and check out her blog.   Jazz lily

Here are the rules for this award…

Rules:

(1) write a post to show your Award

(2) Acknowledge the Blogger that nominated you

(3) Give a brief story about how you get started blogging

(4) Give two pieces of Advice for new bloggers

(5)  Nominate the deserving 15 bloggers

So, here is how it all started. The idea of creating something like a website, which should contain all the stuff related to Science and Technology, was on my mind for so long. Before I started this blog, I don’t know where to start, I literally searched every possible source. In this search, I learnt so much about SEO(search engine optimisation) and stuff, with GREAT struggle, I actually created a free self-hosted website which shows adverticements more than my articles.

And I realised that building a self-hosted website actually need skills which comes through experience. Finally I thought of creating some blog, where I don’t need to worry about anything but content. That is how I came across WordPress.

And my blog’s Title!!

Well… I wanted my blog to be useful, whoever reads it, should be able to understand and finally I wanted it to be cool;)

Advice for new bloggers:

I am not so experienced or famous here. But I have spent more than a year here. So, here are two tips from what i have learned.

  1. Don’t write trending topics only to get readers, write what’s on your mind.
  2. Read and review other blogs…
  3. One extra suggestion for YOU!! People suggest to tag and categorize but they won’t tell how many tags are to be given.. The fact is wordpress do not put your article on to the followed tags portal( where people search and read article on wordpress) if you tags count is more than 15. The same is with the categories…

Finally here’s the tough part of any award post.. NOMINATIONS!!! I have nominated a few of my favorite blogs. Some of he blogs in this list,,, I visit them once in a while just to read the new articles if any.. Many bloggers are fed up with the awards and stopped doing award posts. No problem, do write if interested… But I am so glad for this nomination. Again, thank you so much Sahana for nominating me.

NOMINATIONS:

Sickphysics

Mathsbyagirl

Iridescence

Smiling all the way to heaven

Scientificlove

Gaurish4math

Entropy of consciousness

Richard

t3chagent

Weijie

Keithgarrettpoetry

Wanderingviolet

Arpita

Breezing Whims

Laika

Life event observation

LosiLosLoco

Himali

Science and rationality

Jessie

Never stop exploring

Mithai

Muskanreadsandwrites

 

 

Boomerang!

Boomerangs have been around for thousands of years now. Traditionally, returning boomerangs are lightweight, made of wood, and consist of two separate wings which meet at an angle at the joining.

All boomerangs aren’t made to come back! Some are made just to hit the target. Now let’s see, how a coming back boomerangs work?

The top and bottom portions of a boomerang are made in an aerodynamic shape or an airfoil shape. Top one is Leading edge and the bottom one is trailing edge.  When boomerang is thrown and the air passes through this shape, it results in a lift as shown below.

airfoil_incorrect

When you throw a boomerang, there are two speeds to be considered, one in the forward direction and the other is rotating speed. This makes it fly and rotate at the same time. As the boomerang spins through the air, the wing at the top of the spin is moving through the air at a faster rate than the wing at the bottom. This makes the top portion generate more lift than the bottom portion as it cuts through the air.

brng

Because the top portion of the boomerang is moving faster than the bottom portion, some torque is generated, which makes the boomerang tilt the plane of rotation slightly such that, the boomerang ends up flying in a curved path through the air. This makes the boomerang come back. It’s not easy to catch the boomerang back. It depends on the angle and force with which you throw with..

 

 

All those images are from Google!

 

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