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| Class VI Students Narrating Story |
Wednesday 31 July 2019
Tuesday 30 July 2019
For your Knowledge
What are meteorites made of and where do they come from?
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Meteorites are “space rocks” that are found on Earth after they fall from the sky. While falling, these space rocks race through the air a hundred times faster than an airplane. Travelling this fast makes the space rocks very hot – more than 1,000 degrees Celcius! And that makes them shine, like a star – which is why people call them “shooting stars”.
Most meteors are tiny and burn up as they fall towards Earth. Some bigger ones explode. This happened in 2013 in Russia: a meteor as large as a house exploded above a city of more than a million people.
Some space rocks hit the Earth. This can make a hole in the ground, making what we call a crater. The Earth’s moon is covered with craters, but craters on Earth are usually washed away by rain, or plants grow over them, or they get wiped away when mountains grow. You can still find some pretty big craters on Earth, though, such as the Barringer crater in Arizona, US.
It’s a miracle no one has been hit on the head by one of these space rocks. But many dinosaurs weren’t that lucky 65 million years ago, when a rock the size of London struck Earth. This meteor made the gigantic Chicxulub crater, caused a huge tsunami wave and turned day into night – and it’s the main reason why dinosaurs went extinct.
What meteors are made of
Surely, you’d think, meteors can’t be just like normal stones – well, yes and no. They come in two different types.
One is a bit like stone, and it can be difficult to tell if it’s a meteorite.
The other is like a clump of metal, much heavier than normal stone. These are easier to recognise. Both types have a “skin” that is scorched, as if it had been in a very hot oven.
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| A piece of the Allende meteorite |
Where do meteors come from?
We know there are many rocks that go all the way around the sun, just like the Earth does over the course of one year. The largest one is called Ceres, and it's almost a thousand kilometres wide. Humans can’t see many of the smaller ones… until they hit Earth!
Some of these rocks are called “asteroids”, because they shine like stars. Others are called “comets” because they are more like dirty snowballs that leave a trail behind them.
Asteroids and comets are the crumbs left over after planets like Earth formed, 4.5 billion years ago. Some were also made when two planets crashed into each other.
Many planets, including Earth, are stony on the outside and metallic on the inside. And this explains why meteorites come in two types: the stony ones come from the outsides of those unlucky planets that got in a crash, while the metallic ones come from their insides.
Earth itself got hit when it was still only millions of years young, and that’s how the moon was made.
Meteors from Mars and beyond
When a big meteorite makes a crater, it throws up rocks into space. Those rocks can also land on Earth. Some meteorites come from the moon, and some even from Mars. We know that because inside the meteorites are tiny bubbles of air. The air on Mars is very different from the air on Earth, so we can tell if a rock comes from Mars by examining the air bubbles inside.
Some rocks even come from outside of our solar system. Scientists spotted the first one of these in 2017 – it’s called ‘Oumuamua, and it’s a hundred metres wide. Luckily, it missed Earth.
Plants, animals and insects are all very different creatures. But all life on Earth shares something special, and that’s extremely tiny bits called amino acids. And they have been found inside meteorites! Scientists still aren’t quite sure what this means exactly, but some believe life might have arrived on Earth from space – if that turns out to be true, perhaps we’re all aliens, after all?
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| Oumuamua in flight. ESO/M. Kornmesse |
Saturday 27 July 2019
How do penguins stay warm in Antarctica?
The first thing I should probably say is that while a lot of people think polar bears and penguins live together, in fact they live at opposite ends of the Earth. Polar bears live in the northern hemisphere and penguins live in the southern hemisphere.
I’m a penguin researcher so I’m going to explain here how penguins can stay warm in Antarctica.
There are four species of penguins that live in Antarctica: emperors, gentoos, chinstraps, and Adélies.
All these penguins have special adaptations to keep them warm, but emperor penguins might be the most extreme birds in the world. These amazing animals dive up to 500 metres below the surface of the ocean to catch their prey, withstanding crushing pressures and water temperatures as low as -1.8 degrees Celsius.
But their most incredible feat takes place not in the ocean, but on the sea ice above it.
Surviving on the ice
Emperor penguin chicks must hatch in spring so they can be ready to go to sea during the warmest time of year. For this timing to work, emperors gather in large groups on sea ice to begin their breeding in April, lay their eggs in May, and then the males protect the eggs for four months throughout the harsh Antarctic winter.
It’s dark, windy and cold. Air temperatures regularly fall below -30℃, and occasionally drop to -60℃ during blizzards. These temperatures could easily kill a human in minutes. But emperor penguins endure it, to give their chicks the best start in life.
A body "too big" for its head
Emperor penguins have four layers of overlapping feathers that provide excellent protection from wind, and thick layers of fat that trap heat inside the body.
Have you ever noticed that an emperor penguin’s body looks too big for its head and feet? This is another adaptation to keep them warm.
The first place that you feel cold is your hands and feet, because these parts are furthest from your main body and so lose heat easily.
This is the same for penguins, so they have evolved a small beak, small flippers, and small legs and feet, so that less heat can be lost from these areas.
They also have specially arranged veins and arteries in these body parts, which helps recycle their body warmth. For example, in their nasal passages (inside their noses), blood vessels are arranged so they can regain most of the heat that would be lost by breathing.
Huddle time
Male emperor penguins gather close together in big groups called “huddles” to minimise how much of their body surface is exposed to cold air while they are incubating eggs.
This can cut heat loss in half and keep penguins’ core temperature at about 37℃ even while the air outside the huddle is below -30℃.
The biggest huddles ever observed had about 5,000 penguins! Penguins take turns to be on the outer edge of the huddle, protecting those on the inside from the wind.
Incredibly, during this four-month period of egg incubation the male penguins don’t eat anything and must rely on their existing fat stores. This long fast would be impossible unless they worked together.
Changing habitats
Emperor penguins are uniquely adapted to their Antarctic home. As temperatures rise and sea ice disappears, emperors will face new challenges. If it becomes too warm they will get heat-stressed, and if the sea ice vanishes they will have nowhere to breed. Sadly, these incredible animals may face extinction in the future. The best thing we can do for emperor penguins is to take action on climate change now
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Friday 26 July 2019
Illusion turning reality
Elon Musk Thinks Neuralink Could Merge Humans With AI; Neuroscience Says Wait
According to Musk, Neuralink's goal is to build a "scalable high-bandwidth BMI system". Thus far, the company's scientists and engineers have replicated three cutting-edge inventions.
In 1985, the science fiction writer Bruce Sterling wrote of future worlds inhabited by two groups of humans. The ‘shapers’ believed in altering their bodies using biotechnology and genetic engineering to achieve superhuman capabilities . The ‘mechanists’ used mechanical and electronic alterations to gain the same brain-body advantages.
It’s safe to say that Sterling wasn’t too far off the mark – at least for brain-related modifications. Nowadays, neuroscientists use both genetic and mechanical modifications to study as well as manipulate brain activity. But Elon Musk seems to prefer the mechanists’ approach with his new venture, Neuralink.
Musk delivered a speech followed by a slew of announcements about the technologies Neuralink was working on towards building an advanced brain-machine interface (BMI), on July 16 in California.
A BMI is a broad term for any communication pathway or device that allows humans and animals to translate their brain signals into commands that machines can execute.
According to Musk’s preprint paper, Neuralink’s goal is to build a “scalable high-bandwidth BMI system”. Thus far, the company’s scientists and engineers have replicated three cutting-edge inventions. The first is an ultra-thin electrode to be inserted inside a brain to relay electrical signals between the brain and a computer. The second is a robotic instrument to carefully implant the electrodes. The third is a small chipset to amplify and manipulate the signals.
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A closeup view of the machine that will be used to implant the electrodes. Photo: Neuralink/YouTube
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This technology, Musk said, may eventually help humans merge and communicate with an artificial intelligence (AI). This is a grandiose claim that does little to counteract both the absence of important details in Neuralink’s preprint paper and the fact that Neuralink has essentially repeated research that has already been conducted.
In fact, there is a chasm between the contents of Neuralink’s paper and the possibilities Musk presented in his speech. The road to these possibilities is long and hard, and not without problems. And even as the Neuralink paper is a relatively more detailed source of information than the televised announcement, it can still benefit from a good deal of unpacking in terms of important data that hasn’t been shown and whether Neuralink’s achievements are truly novel or game-changing.
As in many other important things in our world, the devil (or demon, a term Musk used to talk about AI in 2014) is in the details.
To build any BMI system, we need four things:
1. A set of electrodes that can be inserted into the brain to ‘read’ and ‘write’, i.e. record and deliver, electrical activity to neurons around the implant site
2. A device to transform these analog waveform signals into digitised information
3. A wired or wireless connection from the top of the skull
4. A connected computer to analyse and transmit the appropriate signals back into the brain, effectively creating a closed-loop system
It’s very difficult to build a system in which all these components play well with brain tissue. Scientists have been working on ways to tap directly into brain activity since the 1920s. As a neuroscientist who studies electrical activity at the level of neurons, I find it fascinating to decode the activity of neuronal networks. But even with my limited familiarity with BMIs, some of Neuralink’s pieces don’t seem to fit the puzzle very well.
Thursday 25 July 2019
For your knowledge
Why don't we use the Earth's magnetic field to create electricity?
The Conversation is asking kids to send in questions they'd like an expert to answer. A student from Neerim South Primary School in Victoria wants to know why we don't use the magnetic energy the Earth provides to create electricity. An expert in physics explains.
This sounds like a good idea at first, but it’s not very practical. Before I explain why, let me first explain how we generate electricity in case somebody reading this doesn’t already know.
Electricity (let’s say “electrical current”) is when electrically charged particles flow, like water in a pipe. There are two kinds of electrical charge: positive and negative. Positive charges attract negative charges, but two particles with the same charge (both positive or both negative) will repel. That means they push apart.
In other words, opposites attract.
Usually, electrical current is made of tiny negative charges called “electrons” which come from atoms.
Everything you can touch is made of atoms. Every atom is surrounded by a cloud of electrons moving randomly like bees around a beehive, attracted to the positive charges in the centre (or “nucleus”) of the atom.
How to create an electrical current
There are three main ways we produce electrical current.
The first is batteries. In batteries, there is an “electrochemical reaction” that causes electrons to move from one kind of atom onto another kind of atom with a stronger attraction to electrons. A battery is designed to force these electrons to pass through a wire into your electronic devices.
A second way is solar cells. Light energy is absorbed by electrons in something called “semiconductors” (usually silicon) which causes electrons to move, creating electrical current.
But I think you’re asking about the third way that is usually used to generate electrical currents for power sockets in your house.
Spinning a coil of wire in a strong magnetic field
This third way is to move an electrical wire quickly through a magnetic field. You need to do this because electrons in a wire cannot feel the magnetic force unless they are moving.
To get enough current for everybody, you must move a lot of wire through a magnetic field. We do this by spinning a coil (containing many loops of wire) quickly in a strong magnetic field.
During each turn of the coil, electrons get a kick from the magnetic field, moving them along. This creates electrical current. In this animation, S represents the “south pole” of the magnet and N represents the “north pole”. The animation only shows a single loop of wire spinning in the magnetic field. In a real generator, there would be hundreds or even thousands of loops.
Machines that do this are called generators. You can spin the coil using falling water (that’s called “hydroelectricity”), steam (produced from coal, oil, gas, nuclear energy or heat from the Sun), wind turbines that use the wind and so on.
In most generators, each time the coil does half a turn, electrons get a magnetic kick. In the next half-turn, they get a magnetic kick in the opposite direction. This means the direction of the current keeps swapping through many cycles rapidly.
Electrical current which swaps direction is called “alternating current” or AC for short. Batteries produce current that travels only in one direction, called “direct current” or DC for short.
In generators, we are not taking energy out of the magnetic field. The energy going into electrical current is actually coming from the energy used to spin the coil. Scientists call this “kinetic energy”.
Back to the Earth’s magnetic field
Now (finally!) to answer your question: why don’t we use Earth’s magnetic field to generate electricity?
The amount of current a generator produces depends mostly on at least three things: 1) how many loops of wire in the coil, 2) how fast the coil is spun and 3) how strong the magnetic field is.
Earth’s magnetic field is very weak, so you would get very little current from your generator.
How weak? Have you ever seen those button-shaped neodymium-iron-boron magnets, also called “neo-magnets”? (Be careful – they can really pinch you).
They have magnetic fields around 6,000 times stronger than Earth’s magnetic field. Magnetic fields inside electrical generators are similar to this.
Even fridge magnets have magnetic fields approximately 200 times stronger than Earth’s.
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Wednesday 24 July 2019
For Your Knowledge
SWACHH BHARAT MISSION
Introduction
Launched by Prime Minister Narendra Modi on October 02nd, 2014 with an estimated cost of around Rs 62,000 crore, Swachh Bharat Mission aims to cover 1.04 crore households, provide 2.5 lakhs seats of community toilets, 2.6 lakhs seats of public toilets and solid waste management facility for all towns.
How it is being managed
The urban component of the mission is being managed by the Union Ministry of Urban Development. Around three million government employees and school and college students of India participated in the event in its initial phase. The rural component of the mission is being handled by the Union Ministry of Drinking Water and Sanitation.
Historical Development:
The Total Sanitation Campaign (TSC)
In 1999, the Union Government rolled out the Total Sanitation Campaign (TSC). Its objective was to spread awareness among the rural people and generation of demand for sanitary facilities. The scheme was implemented with emphasis on community-led initiatives. The government provided financial incentives to the families which were Below Poverty Line (BPL). The government assistance was also extended for construction of toilets in the primary schools, the ‘Anganwadi’ Centres and the Community Sanitary Complexes (CSC).
The Nirmal Bharat Abhiyan (NBA)
The Government of India also launched the Nirmal Gram Puraskar (NGP) to recognise contributions in this field. NGP became a success which prompted the Government to rename CSC as the Nirmal Bharat Abhiyan (NBA). Its objective was to accelerate the sanitation coverage in the rural areas. This scheme was handled by the Ministry of Rural Development.
Under Nirmal Bharat Abhiyan, the government adopted the community-centric strategies. The demand driven approach continued highlighting awareness creation and demand generation for sanitary facilities in houses, schools. It also emphasised on a cleaner environment.
Emergence of the Swachh Bharat Abhiyan
However, programmes like the Total Sanitation Campaign and the Nirmal Bharat Abhiyan failed to achieve the desired targets due to planning weaknesses, wastages, and irregularities. According to the CAG estimation, more than 30 percent of individual household latrines were defunct/non-functional for reasons like poor quality of construction, incomplete structure, and no-maintenance.
It states that though the conceptual framework keeps changing from supply driven to demand driven and finally to ‘saturation and convergence’ approach, the lessons learned and experimentations do not seem to have made much impact on the sanitation status in the country. We need to learn from the previous mistakes.
With the introduction of the Swachh Bharat Abhiyan in 2014, the Government restructured the Nirmal Bharat Abhiyan (NBA) with two sub-Missions: Swachh Bharat Mission (Rural) and Swachh Bharat Mission (Urban). The focus now is to achieve a clean, defecation-free India by the year 2019.
Conclusion
It would be a befitting tribute to the Father of Nation on his 150th Birth Anniversary, if we can improve the levels of cleanliness in the country and make it Open Defecation Free. But the success of Swachh Bharat Mission depends on the society as a whole with every citizen of the country required to contribute towards improving the levels of cleanliness in the country.
For More such article :- https://www.indiacelebrating.com/article/article-on-swachh-bharat-abhiyan/
Students view on Chandrayaan 2
What Kendriya Vidyalaya Manendragarh student has to say about Chandrayaan 2
Tuesday 23 July 2019
Did you Know?
How did people clean their teeth in the olden days?
Dental hygiene has come a long way since the days of wine-soaked toothpicks and the urine mouthwash once thought to disinfect mouths and whiten teeth.
Some of the earliest tooth-cleaning artefacts archaeologists have found are ancient toothpicks, dental tools and written tooth-care descriptions dating back more than 2,500 years. Famous Greek doctor Hippocrates was one of the first to recommend cleaning teeth with what was basically a dry toothpaste, called a dentifrice powder.
Ancient Chinese and Egyptian texts advised cleaning teeth and removing decay to help maintain health. Some of the early techniques in these cultures included chewing on bark or sticks with frayed ends, feathers, fish bones and porcupine quills. They used materials like silver, jade and gold to repair or decorate their teeth.
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| Early techniques of cleaning teeth included chewing on bark or sticks with frayed ends, feathers, fish bones and porcupine quills |
People in the Arabian Peninsula, North Africa and the Indian subcontinent traditionally cleaned their teeth with chew sticks made from the Salvadora persica tree. They’re called miswak. Europeans cleaned their teeth with rags rolled in salt or soot.
Believe it or not, in the early 1700s a French doctor named Pierre Fauchard told people not to brush. And he’s considered the father of modern dentistry! Instead, he encouraged cleaning teeth with a toothpick or sponge soaked in water or brandy.
In the late 1700s, Englishman William Addis was the first to sell toothbrushes on a large scale. He got the idea after making a toothbrush from bone and animal bristles while in prison.
Before modern-day toothpaste was created, pharmacists mixed and sold tooth cream or powder. Early tooth powders were made from something abrasive, like talc or crushed seashells, mixed with essential oils, such as eucalyptus or camphor, thought to fight germs. Their flavors came from oils of cinnamon, clove, rose or peppermint. Many contained other chemicals such as ammonia, chlorophyll and penicillin. These ingredients fight the acid-producing bacteria that can cause tooth decay and bad breath
By the 1900s, children of immigrants to the US were taught oral hygiene as a way to help "Americanise" them and their families. Factories examined and cleaned their workers’ teeth to keep them from missing work due to toothaches.
Daily tooth brushing became more common thanks to World War II, when the American army required soldiers to brush their teeth as part of their daily hygiene practices. The first nylon toothbrush was made in 1938, followed by the electric toothbrush in the 1960s.
Nowadays, there are dozens of kinds of tools and potions to help keep your mouth healthy. As a professor of dental hygiene, I believe it’s most important to clean your mouth daily, no matter how you choose to do so. Well, maybe stay away from the urine mouthwash
Source : For More Such article visit
http://education.abc.net.au/newsandarticles/blog/-/b/3245135/curious-kids-how-did-people-clean-their-teeth-in-the-olden-days-For your Knowledge
JAN DHAN YOJANA
Jan-Dhan Yojana is a national mission to connect every Indian (especially weaker sections and low income groups people) to various financial services (such as saving bank account, need based credit, remittances facility, insurance and pension) using advance technology. Jan Dhan Yojana is also known as Pradhan Mantri Jan Dhan Yojana as it was run by the Indian Prime Minister, Narendra Modi as a People Money Scheme to add each and every people of India to the bank account and savings
Jan Dhan Yojana is an account opening and money saving scheme especially made by the Indian Prime Minister, Narendra Modi for the poor people of India to connect them to the bank account and give all the benefits of the opening account. This scheme was launched by the PM on 28th of August two weeks later to the Indian Independence Day. This account opening and money saving scheme was launched as a national challenge to bring each and every Indian citizen to the bank and connect to its benefits.
Many programmes have been implemented to make this scheme a successful scheme. Around 60,000 enrolment camps has been set up in the rural areas to draw people’s mind, explain them about the processes and benefits of opening bank account as well as make them aware about the importance of bank accounts
Monday 22 July 2019
trending Technology
Introduction to AI and machine learning
Artificial intelligence (AI) is the general study of making intelligent machines. Machine learning (ML), a subset of AI, focuses on the ability of machines to receive data and learn for themselves without being programmed with rules. ML differs from traditional programming by allowing you to teach your program with examples rather than a list of instructions. Instead of writing instructions, or rules, while programming, machine learning enables you to "train" an algorithm so that it can learn on its own, and then adjust and improve as it learns more about the information it is processing.
In the content below, you can start building a basic understanding of AI and ML, learn about ML terminology, and explore interactive demos to see the things you can do with ML
Lets Make it More simple ...... CLICK Here
Artificial Intelligence In 5 Minutes | What Is Artificial Intelligence?
Types Of Artificial Intelligence | Artificial Intelligence Explained
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