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Explained: Physics related to everyday life

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Image-epi.edu.com

By Aakash Sinha

When I was a child, many unusual questions used to trigger my mind, some I got the answers and rest are still unexplored. Human is a social animal with brains. We have got a special ability, we can reason. In our day-to-day life, we come across several stuff which we accept it without knowing the cause of that activity. But the question is why? How?

In this article, we will see the reason behind some of the activities that we see every day but never questioned about it.

Why the wheels of any vehicle are circular?

  • Quite interesting! I noticed it when I was 12 years old. Well, everyone uses a cycle, bike or a car, watching the wheels every day. But, why can’t the wheels be rectangular or square? Why circular? There is the force that opposes every force called friction force. We can walk, run & stop; all due to this force. Wheels of the automobiles are made circular to reduce the frictional force. On a circular body, rolling friction acts which is less than the sliding friction (a type of friction that acts on all bodies other than circular) which is responsible for the wheels to be circular. If wheels would have some other shape, sliding friction would come into picture increasing the resistance in movement of automobiles.

Why tube light blinks before turning ON?

  • Every day we come across this phenomenon but the reason remains unnoticed. A tube light has a low-pressure mercury vapour with a phosphorous coating, white in colour which we can see from our eyes. When the tube light is turned ON, it flickers. That flicker is caused because the gas inside the lamp is relatively cold and cannot establish glow discharge between the two electrodes. Once the heat is developed, gas ionizes and gives out the ultraviolet light enabling the phosphorous coating to glow.

Why the moon looks bright yellow at night?

  • Moon is connected to humans involving different emotions and expressions. Moon does not have its own light. It is just an illusion. Then, how does it shine? That bright colour of the moon is due to the reflected light from Sun which bounces off the dark grey and bumpy surface of the celestial body, falling on our eyes. The shocking fact is that only 3% to 12% of light is reflected from the surface of the moon but still the brightness is more than a star. We can see the moon during day time but we can’t see the stars.

Why do stars twinkle at night?   

  • Twinkle- Twinkle little star….. The poem taught to every child always tickled my mind when I was 16. Our Earth atmosphere is very turbulent and made up of different layers of air moving in all directions at different intensities. Light from the stars travel a very long distance before falling on our eyes. When it passes through the atmosphere, it bends due to refraction which makes it appear to twinkle. The Scientific name of the twinkling of stars is ‘astronomical scintillation’. Thank God! The poem was not written by a scientist.

Why the sky is blue in colour?

  • The rays of the sun are made of 7 colours (Violet, Indigo, Blue, Green, Yellow, Orange, and Red). As the white light passes through Earth’s atmosphere, it collides with particles of air. The different colours or wavelengths of light are scattered by this collision by different amounts. Blue light (shorter wavelength) is scattered more than red light (longer wavelength).When sun is high in the sky, blue light is scattered in all directions and sky appears blue.

How water comes inside the coconut?

  • Clusters of coconut palms thrive on seashore outside the tidal zone provided there should be a plenty of subterranean fresh water. As the fresh water accumulated by the roots is conveyed right up to the crowns of the coconut palms through osmosis process, any dissolved salts which exist in that water is eliminated through natural filtration. The water inside the coconut is actually ‘endosperm’ or the food or the nourishment for the coconut’s growth. As the coconut ripens the water becomes less pleasant to drink.

How does water come on Earth?

  • After the big bang almost 13.8 billion years ago, the energy that sparkled in the Milky Way galaxy lead to the formation of Earth. That time Earth was boiling at a very high temperature. The water we have today came into existence much after the formation of the blue planet (Earth). Comets and asteroids can contain ice. The collision of wet comets and asteroids is responsible for the existence of life-giving liquid, “water” on Earth. The study shows that meteorites from Vesta (a group of meteors near to Jupiter) have the same chemical makeups (rocks) as that of our Earth. The mystery is not yet solved, but suspects’ asteroids.

How a program recorded in a studio reaches our Television sets?

  • We enjoy watching different programs on T.V but we never think of the engineering behind the telecasting of any program. There are three divisions of a Television station:-
  • Studio
  • Earth Station
  • Transmitter

A studio is the action area of artists where they perform any act. When the program is recorded it is sent to the Earth Station via cables. Earth station is a terrestrial terminal station designed to uplink and downlink data (programs) to and fro from the satellite. Once the program is uplinked to the satellite it can be viewed in any part of the country using the transmitter and receiver unit (at home, DTH). The program is downlinked at a T.V tower unit, then the different frequency is embedded for different programs (for DD News= 224.5MHz) in the form of electromagnetic waves. These waves are then transmitted in the air through an antenna. Now the same frequency is identified by the T.V receiver, it decodes it and we can see the desired program.

Have you ever noticed the direction of your DTH antenna? 

  • Once I was standing on the terrace, I observed that all the antenna of DTH is pointing towards the same direction. I was amazed. That dish antenna points towards the satellite of the country from where it can receive the signals (Radio frequency). In India, every dish antenna points towards South-East.

We cannot solve the problems with the same thinking we used when we created them – ALBERT EINSTEIN

Aakash is a student of engineering at Sir M. Visvesvaraya Institute of Technology, Bangalore. Twitter @aakashsinha1994

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Giant planet orbiting a small star find stuns scientists: NGTS Survey

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(image:wikipedia)

London, Nov 1,2017: An international team of astronomers has found a gas giant the size of Jupiter orbiting a star half the size of the Sun, a discovery that challenges theories of planet formation which state that a planet of this size could not be formed by such a small star.

This unusual planet, NGTS-1b, is the largest planet compared to the size of its companion star ever discovered in the universe, according to the study to be published in an upcoming issue of the journal Monthly Notices of the Royal Astronomical Society.

“The discovery of NGTS-1b was a complete surprise to us — such massive planets were not thought to exist around such small stars,” said lead author of the research Daniel Bayliss from the University of Warwick in England.

According to existing theories of planet formation, small stars can readily form rocky planets but do not gather enough material together to form Jupiter-sized planets.

The planet NGTS-1b which is six hundred light years away from Earth is a hot Jupiter, at least as large as the Jupiter in our solar system, but with around 20 per cent less mass.

It is very close to its star — just three per cent of the distance between Earth and the Sun – and orbits the star every 2.6 days, meaning a year on NGTS-1b lasts two and a half days.

The temperature on the gassy planet is approximately 530 degrees Celsius, or 800 kelvin.

The researchers spotted the planet using the Next-Generation Transit Survey (NGTS) – a wide-field observing facility made of a compact ensemble of telescopes, designed to search for transiting planets on bright stars – run by the Universities of Warwick, Leicester, Cambridge, Queen’s University Belfast, Observatoire de Genève, DLR Berlin and Universidad de Chile.

The planet orbits a red M-dwarf — the most common type of star in the universe, leading to the possibility that there could be more of these planets waiting to be found by the NGTS survey.(IANS)

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Astronomers discovered Sun-like star that devoured its own planets

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Astronomers discovered Sun-like star that devoured its own planets

New York, Oct 13: Astronomers have discovered that a Sun-like star lurking around 350 light-years away consumed the rocky equivalent of 15 Earths.

Dubbed Kronos after the child-eating Titan of Greek mythology, the star is the clearest and most dramatic case yet of a Sun-like star consuming its own planets, said Semyeong Oh, astrophysicist at Princeton University in New Jersey and lead author of the study.

“Even if our Sun ate the entire inner solar system, it wouldn’t come close to the anomaly we see in this star,” study co-author David Hogg from the Flatiron Institute in New York added.

The research did not begin as a hunt for a planet-eater.

Oh was analysing a catalog of new star data collected by the European Space Agency’s Gaia spacecraft for pairs of stars with similar speeds and trajectories.

Such duos are typically twin stars that formed close together from the same ingredients.

The analysis ultimately led to the identification of Kronos and its lesser known brother Krios.

Their official designations are HD 240430 and HD 240429, and they are both about 350 light years from Earth.

The keys to the discovery were first confirming that the widely separated pair are in fact a binary pair, and secondly observing Kronos’ strikingly unusual chemical abundance pattern, Oh explained in a statement released by the Princeton University.

Other co-moving star pairs have had different chemistries, Oh explained, but none as dramatic as Kronos and Krios.

Most stars that are as metal-rich as Kronos “have all the other elements enhanced at a similar level,” she said, “whereas Kronos has volatile elements suppressed, which makes it really weird in the general context of stellar abundance patterns.”

In other words, Kronos had an unusually high level of rock-forming minerals, including magnesium, aluminium, silicon, iron, chromium and yttrium, without an equally high level of volatile compounds — those that are most often found in gas form, like oxygen, carbon, nitrogen and potassium, the study said. (IANS)

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Researchers Claim The Existence Of Planet Nine

Researchers from an American University have laid evidences to prove the presence of Planet Nine

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Planet Nine
Kuiper Belt indicates the presence of Planet Nine
  • The science communities since a long time have been debating upon the existence of Planet Nine. 
  • Space highlights different shreds of evidence based on which scientists are stating the claim.

What Is Planet Nine?

Planet Nine is a hypothetical planet present in the far outer Solar System, whose mass is estimated to be 10 times more than the mass of Earth. The planet is said to be 20 times farther than the sun than Neptune is.

What Do Researchers Have To Say?

Dr Konstantin Batygin, a planetary astrophysicist at the California Institute of Technology, said that there were five different lines of observational evidence which pointed to the existence of Planet Nine. He stated that if this theory does not sound believable, then people would have to come up with the answers of the five pieces of evidence which could lead to further confusion.

Also Read: Five Students from Telangana Selected for the NASA Human Exploration Rover Challenge

Batygin in 2016 published a study examining the six known objects in the Kuiper Belt, a  circumstellar disc in the Solar System beyond the planets that extends from the orbit of Neptune towards interstellar space.

The study examines all the objects have elliptical orbits pointing in the same direction and are tilted the same way. These serve as evidence to the planet’s existence.

It is being said that the objects are tilted 30 degrees downward compared to the plane where the eight official planets circle the sun. Researchers also made use of computer simulations of the solar system including the Planet Nine and to demonstrate that there should be more objects tilted a whopping 90 degrees to solar plane. It was revealed that five such objects, which fit these parameters were already known.

The study led to the birth of two more ideas. Researchers said that this planet could have tilted the planets of the solar system during the last 4.5 billion years.

Planet Nine’s existence could also tell the reason as to why Kuiper Belt objects orbit in the opposite direction as compared to other things in the solar system.

-Prepared by Megha Acharya of NewsGram.

(the story was originally published in PTI)