SCIENCE & TECHNOLOGY

Wireless power
Dr S.S.Verma

Electric power is the deriving engine of our present-day life in general and electronic life in particular. As technology is constantly changing, one of the greatest tools to the do-it-our- self is the extension cord or battery.

Love in a pill possible?
Could a pill or a squirt up your nose save your marriage? Maybe, according to a researcher who is studying the chemical basis of that most elusive of emotions — love. Larry Young says his ultimate quest is not a high-tech love potion but to shed light on serious conditions like autism, which affects the ability to form social attachments, by studying brain chemicals involved in emotional attachment.

Trends
Black holes may precede galaxies

Black holes — those massive, invisible objects that suck in everything around them — may have appeared before the galaxies that host them, astronomers said on Wednesday. The findings could change the understanding of how galaxies first formed, and what role black holes play in the universe.


Prof Yash Pal
Prof Yash Pal

THIS UNIVERSE
Why do our eyes get tears?
PROF YASH PAL

I have discovered that coming of tears is a phenomenon, which has  multiple  connections.  Let us first look at the reason  for storage of slightly salty water near our eyes.  The beautiful engineering design of our eyes is truly amazing. The obvious components like the lens, the retina on which the image is formed, the manner in which the image is broken up into its colour components and the transmission of all this information to the brain are truly great scientific marvels. This we all respect and greatly appreciate.

 

 


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Wireless power
Dr S.S.Verma

Electric power is the deriving engine of our present-day life in general and electronic life in particular. As technology is constantly changing, one of the greatest tools to the do-it-our- self is the extension cord or battery.

Extension wires for the supply of electric power inside and outside the houses need a big infrastructure with problems like safety, space and cost. Batteries to some extent (viz., in small requirements of power) have replaced the plug source of electric power but recharging, cost and battery life are the hurdles of battery technology. So there is a need to invent wireless power.

The concept is at least as old as Nikola Tesla, the turn-of-the-20th-century icon who used to demonstrate the wonders of electricity and was trying to demonstrate the transfer of beam energy from one point to another without any wires but could not finish the project. Thus, the transfer of electric power without wires (i.e., wireless power supply) just like data/information transmission with electromagnetic waves has always been a subject of interest to scientists, engineers and general public and with the progress of science and technology this topic is no more confined to science fiction stories but is progressing towards reality.

Scientists have shown that one can generate power, convert it to lasers or microwaves, beam it to another point and reconvert it into electricity. Hence, wireless power is going to be essential to the next generation of mobile electronic devices and it’s only a matter of time before we have it.

Of course, transferring energy wirelessly is nothing new in itself. Electricity is routinely transferred in this way in transformers using induction; radio frequency identification (RFID) chips are energised by radio waves emitted from RFID readers; and for years, researchers have worked on transferring energy over long distances using microwaves with obvious limits. Although a lot of power can be passed through a transformer, the energy typically can be transmitted only a few millimeters inside the transformer.

RFID readers do have a longer range, but little power can be transmitted to the chips. Microwave systems can transmit fair amounts of power over long distances, but they are bulky and have to use a tightly focused beam that must be precisely pointed at the receiver to keep the energy from being hopelessly dissipated.

New research reveals a way to send wireless energy to mobile phones and laptops. The wireless transfer of energy is used in various devices, such as electric toothbrushes, mobile phones, laptops, the transcutaneous energy transfer (TET) systems in artificial hearts like AbioCor.

Others have imagined terrestrial networks of power-beaming stations that could fuel electric cars and other vehicles. One long-sought application is aviation. A fully developed World System would, conceivably, allow for the removal of many existing high-tension power transmission lines, and facilitate the interconnection of electrical generation plants on a global scale.

The principle that energy can be transmitted without a direct physical connection is revealed by simple demonstration: briefly touching the ends of a wire to the poles of a small battery while holding the body of the wire near a compass needle will induce motion of the needle twitching; by the Newtonian axiom that energy is required to induce movement, this simple experiment observes the transmission of energy wirelessly. The needle moves because the electrical current which briefly flows through the wire generates a coaxial magnetic field which acts on the needle by magnetic induction. Another, more dramatic demonstration of wireless energy uses a radio transmitter generating more than a few watts, such as an amateur radio transmitter. A fluorescent lamp with no wires attached to it, held near the antenna, will glow when the transmitter is activated.

Thus, there are several interesting approaches to wireless power. One is to build a broad spectrum radio receiver that can absorb ambient energy from all the microwave and radio transmissions that constantly bombard us. But chances are a single device of this nature would not be able to tap very much energy since radio energy decreases inversely with distance from the transmitter. Another approach might be a peer-to-peer wireless energy grid in which a set of devices that are near to one another all suck down ambient energy and contribute it to a local wireless energy grid. Devices can beam energy to other nearby devices that need it more efficiently than is possible via radio — perhaps using a laser or local induction etc. Scientists are also developing wireless energy transmission using “resonance” a phenomenon that causes an object to vibrate when energy of a certain frequency is applied. By exploiting the resonance of electromagnetic waves, energy can tunnel from one object to the other. Ideally however, using magnetically generated energy is probably going to be better as theoretically it is more efficient.

With the basic principle thus established, the challenge then is to channel the energy of transmission to ensure efficient reception, whereupon it can be converted into useful power. Early systems were incapable of such focused manipulation of electromagnetic energy because the necessary antenna size is impractically large at extremely low radio wave frequencies; lacking focus, much of the transmitted energy would be lost to the atmosphere. The advent of technology for much higher transmission frequencies, like those used by microwave transmitters, created the possibility of relaying electromagnetic energy through the application of directional antennas Lasers, which create a coherent and tightly confined beam of light energy, are even more appropriate.

Focusing the energy and getting viable efficiency are still challenges, and it’s not clear that this will be a long distance solution. Still, before starting to put everything for wireless power transmitters the scheme has a few practical hurdles to overcome. The major concern is that in practice it will be impossible to stop the system from radiating at least some electrical energy into the surrounding environment, where it could be absorbed by objects — including people and other biological organisms. Con-versely, using the magnetic field would be much safer and could be implemented just as easily.

The writer is from Department of Physics, S.L.I.E.T., Longowal

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Love in a pill possible?

Could a pill or a squirt up your nose save your marriage? Maybe, according to a researcher who is studying the chemical basis of that most elusive of emotions — love.

Larry Young says his ultimate quest is not a high-tech love potion but to shed light on serious conditions like autism, which affects the ability to form social attachments, by studying brain chemicals involved in emotional attachment.

“Biologists may soon be able to reduce certain mental states associated with love to a biochemical chain of events,” Young, of the Yerkes National Primate Research Center at Emory University in Atlanta, wrote in the journal Nature.

His study of prairie voles has shown that a quick dose of the right hormone can drastically alter relationships.

The cute rodents are a good model for human relationships, Young said. Unlike many other animals, they form lifelong pairs and raise their young together.

But this behavior is easy to change, Young says.

“It’s a chemical reaction. At least in voles we know that if you take a female and place her with a male and infuse her brain with oxytocin, she will quickly bond with that male,” he said in a telephone interview.

Taking away her natural levels of oxytocin — a hormone involved in labor, nursing and social bonding — means she will reject a male as a mate no matter how many times she physically copulates with him. —Reuters

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Trends
Black holes may precede galaxies

Black holes — those massive, invisible objects that suck in everything around them — may have appeared before the galaxies that host them, astronomers said on Wednesday.

The findings could change the understanding of how galaxies first formed, and what role black holes play in the universe.

Most or all galaxies are believed to have black holes at their centres. Just last month astronomers confirmed that our own Milky Way galaxy has a black hole at its centre.

Researchers told a meeting of the American Astronomical Society in Long Beach, California, that they had seen a clear link between the size of a black hole, as measured by its mass, and the galaxy where it was found. —Reuters

How did reptiles fly?

The Jurassic version of jumbo jets — huge flying creatures weighing hundreds of pounds — is a mystery of dinosaur-era flight: How did something so big get off the ground? A Johns Hopkins University biologist thinks he has figured out the answer.

What people think of as “flying dinosaurs” but are technically giant reptiles didn’t launch into the air like birds. They leapt into the air off all four legs, said Mike Habib, of the university’s Center for Functional Anatomy and Evolution. Only vampire bats do something like that. — AP

Levitating tiny objects

U.S. scientists have found a way to levitate the very smallest objects using the strange forces of quantum mechanics, and said on Wednesday they might use it to help make tiny nanotechnology machines.

They said they had detected and measured a force that comes into play at the molecular level using certain combinations of molecules that repel one another.

The repulsion can be used to hold molecules aloft, in essence levitating them, creating virtually friction-free parts for tiny devices, the researchers said.

Federico Capasso, an applied physicist at Harvard University in Massachusetts, whose study appears in the journal Nature, said he believed that detection of this force opened the possibility of a whole new class of tiny gadgets. —Reuters
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THIS UNIVERSE
Why do our eyes get tears?
PROF YASH PAL

I have discovered that coming of tears is a phenomenon, which has  multiple  connections.  Let us first look at the reason  for storage of slightly salty water near our eyes.  The beautiful engineering design of our eyes is truly amazing. The obvious components like the lens, the retina on which the image is formed, the manner in which the image is broken up into its colour components and the transmission of all this information to the brain are truly great scientific marvels. This we all respect and greatly appreciate. 

But after all this was done the great designer thought of additional things without which all the wonderful optics would have been easily degraded or destroyed. First of these was to provide covers for protection of the lens and also to stop the light from going in to disturb us when we are sleeping. That is why how eyelids were provided. The eyelids were also equipped with eyelashes, not to make the eyes look beautiful, but to protect them from tiny flying insects and dust. Even after that there was appreciation of the fact that some finer dust and other things could go and settle on the cornea and mess up the images coming from outside, besides damaging the eye. 

For this a windshield washing system was thought of. The salty water storage tank was located near the eyes. But the storage tank was not enough by itself. You also needed a pump the way you do for the car windshield wipers. Blinking of the eye provided the pump and, simultaneously, the wiper. The wiper cleaned the eye and spread a uniform thin layer of the fluid on the surface to provide a clear vision. What an efficient and economic design! Frequent blinking of the eye ensures that the thin water layer is uniformly spread.  In the end the designer also thought of a drain for the outgoing liquid. This is a tiny tube connecting the corner of the eye with the  nasal passage.

Finally, let us come to the exact question. Tears come from the same vessel of stored water that is installed for cleaning the eye. At the time when we are sad and unhappy or otherwise emotionally affected our facial muscles contort. This is an observed fact. I do not know why that happens but one of the accompanying effects is that contorting muscles near our eyes operate the pumps, normally done through the blinking of eyes. This pushes in the stored liquid into our eyes at an excessive rate and tears begin to slide down our cheeks.

Is it true that during an earthquake, if a standing person loses his balance and falls, then there are chances of paralysis? Is there any change in gravity during earthquake? If yes, then what is the effect on human brain ?

No, this cannot be true that there is something special in being hurt by falling during an earthquake. Yes the chance of falling, or being injured is greater during an earthquake calamity, but a car accident can produce injuries as bad as any earthquake. There might be some slight change in local gravitational field after a major tectonic upheaval, but nothing that would affect the brain. The trauma of destruction all around is more potent. Please do not believe such superstitions.

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