FLY BY PHYSICS

Introduction

For thousands of years, people have wanted to fly. Our legends and fairy tales are full of humans and animals that can fly –effortlessly gliding through that air. In real life, of course, no one can just fly into the air. We don’t have wings to keep and a power to keep the wings moving through the air to sustain the lift necessary or flight.

 “ Planes and birds are both affected by same forces in flight. They have to able to provide enough lift force to oppose the weight force.”

Our attempts to fly have taken us from flimsy paper hot-air balloons and strange-looking gliders to supersonic jet planes. We have learned about the forces of flight, and we know what it takes to keep birds and planes in the air.

Force can be defined as a push or pull. Unbalanced forces produce an acceleration of an object in the direction of the resultant force. Four main forces affect the flight abilities of birds and planes-weight, lift, thrust and drag.

Weight and Lift

We all know the gravity is a force that pulls everything towards the earth’s surface. This pull is called weight force.

Planes and birds have to be able to provide enough lift forces to oppose the weight force. Lift is a force that acts upwards against weight and is caused by the air moving over and under the wings.

Thrust and Drag

The power source of a bird or plane provides the thrust. Thrust is the force that moves the object forward. Thrust is provided by:

·       Muscles –for birds and other flying animals.

·       Engines-for flying machines.

·      Gravity-for glides that actually fly by always diving at a very shallow angle (birds do this too when they glide).

The force working against thrust is called drag. It caused by air resistance and acts in the opposite direction to the motion. The amount of drag depends on the shape of the objects, the density of the air and the speed of the object. Thrust can overcome or counteract the force of drag.

How it works

An object in flight is constantly engaging in a tug of war between the opposing forces of lift, weight, thrust and drag. Flight depends on these forces-whether the lift force is greater than the weight force and whether thrust is greater than drag forces.

Lift and drag are consider aerodynamic forces because they exist due to the movement of an object through the air. The weight pulls down on the plane opposing the lift created by air flowing over the wing. Thrust is generated by the propeller and opposes drag caused by air resistance. During take-off, Thrust must counteract drag and lift must counteract the weight before the plane can become airborne.

If  a plane or bird flies straight at a constant speed

·        Lift force upwards=weight force downwards

·        Thrust force forward=opposing force of drag

A plane can lose altitude by reducing thrust. Drag becomes greater than thrust and the plane slow down. This reduces lift and the plane descends.

A scientific fact

our human bodies can shied up to 1.5 liters of water   flying in the air for an average 3 hours. This is due to dehydration where we are spending a certain amount of time in a reduced oxygen environment.

Historical fact

The wright brothers invented and flow the first airplane in 1963 it is considered the worlds first sustained and controlled heaviest than air power flight. Their air craft the “height flyer” How about 120 feet.

Conclusion

long flights come when these four drag gravity and thrust and lift are balanced some planes are meant to be theorem with a lot of four because on extra thrust to over come gravity long distance files are often built with this same design planes that are built to spend a long time in the air usually have a lot of lift but little thrust thus planes and birds fly a slow and gentle flight.

SUBMITTED BY:

Shayana

Sujith

Lalan T B

Thilaka

1st  M. Sc. {2^nd Semester}     

SUBMITTED ON: 20/04/2019

REFERENCE:

Internet

journal

AURORA

Introduction:

A Natural electrical phenomenon characterized by the appearance of streamers of reddish or greenish light in the sky , especially near the northern or southern magnetic pole . The effect is caused by the  interaction of charged particles from the sun with atoms in the upper atmosphere. In northern and southern regions it is respectively called AURORA BOREALIS or Northern lights and AURORA AUSTRALIS or Southern Lights.

An Aurora( plural : auroras or aurorae ) ,sometimes referred to as polar lights , northern lights, southern lights , is a natural light display in the earth’s sky, predominantly seen in the high – latitude regions.

Auroras are produced when the magnetosphere is sufficiently disturbed by the solar wind that the trajectories of charged particle in both solar wind and magnetospheric plasma, mainly in the form of electrons and protons, precipitate them into the upper atmosphere due to Earth’s magnetic field, where their energy is lost.

An Aurora is the impressive end result of a series of events that starts at the sun. The sun constantly emits a stream of charged particles known as the solar wind into the  depths of the solar system. When these particles reach a planet, such as Earth, they interact with the magnetic field surrounding it ( the magnetosphere ), compressing the field into a teardrop shape and  transferring  energy to it.

Because of the way the lines of a magnetic field can change, the charged particles inside the magnetosphere can then be  accelerated into the upper atmosphere . Here they collide with molecules such as nitrogen and oxygen, giving off energy in the form of light . This creates ribbon of colour that can be seen across the sky close to the planet’s magnetic north and south poles – this is the aurora.

Gas giant auroras:

Using measurements from spacecraft, such as Cassini, or images from telescopes, such as the Hubble Space Telescope, space physicists have been able to verify that some of our closest neighbours have their own auroras. Scientists do this by studying the electromagnetic radiation received from the planets, and certain wavelength emissions are good indicators of the presence of auroras.

Each of the gas giants (Jupiter, Saturn, Uranus and Neptune) has a strong magnetic field, a dense atmosphere and as a result, its own aurora. The exact nature of these auroras is slightly different from Earth’s, since their atmospheres and magnetospheres are different. The colours, for example, depends on the gases in the planet’s atmosphere. But the fundamental idea behind the aurora is the same.

Interaction of solar wind:

The solar wind is a constant outflow of electrons and protons from the Sun, always present and buffeting Earth’s magnetic field. The background solar wind flows at approximately one million miles per hour.

Even though auroras are best seen at night, they are actually caused by the sun. The sun sends us more than heat and light; it sends lots of other energy and small particles our way. The protective magnetic field around Earth shields us from most of the energy and particles, and we don’t even notice them.

But the sun doesn’t send same amount of energy all the time. There is a constant streaming solar wind and there are also solar storms. During one kind of solar storm called a coronal mass ejection, the sun burps out a huge bubble of electrified gas that can travel through space at high speeds.

When a solar storm comes toward us, some of the energy and small particles can travel down the magnetic field lines at the north and south poles into Earth’s atmosphere. There, the particles interact with gases in our atmosphere resulting in beautiful display of light in the sky. Oxygen gives off green and red light. Nitrogen glows blue and purple.

A typical aurora display consists of these forms appearing in the above order throughout the night.

• Red: At the highest altitudes, excited atomic oxygen emits at 630nm; low concentration of atoms and lower sensitivity of eyes at this wavelength makes this colour visible only under more intense solar activity. The low number of oxygen atoms and their gradually diminishing concentration  is responsible for the faint appearance of the top parts of the “curtains”. Scarlet, Crimson and carmine are the most often seen hues of red for the auroras.

• Green :  At lower altitudes, the more frequent collisions suppress the 630 nm mode: rather the 557.7 nm emission dominates. Fairly high concentration of atomic oxygen and higher eye sensitive in green makes auroras the most common.

•Blue: At lower altitudes, atomic oxygen is uncommon, and molecular nitrogen and ionized molecular nitrogen take over in producing visible light emission, radiating at a large no. of wavelengths in both red and blue parts of the spectrum, with 428 nm being dominant.

•Ultraviolet:  Ultraviolet radiation form auroras have been observed with the requisite equipment. Ultraviolet aurora have also been seen on Mars, Jupiter and Saturn.

•Infrared: Infrared radiation, in wavelengths that are within the optical window, is also part of many auroras.

•Yellow and pink are a mix of red and green or blue. Other shades of red, as well as orange, may be seen on  rare  occasions.

How does the altitude effect the colour of the aurora?

The strong , green light originates at altitudes of 120km to 180km. Red northern light occurs at even higher altitudes, while blue and violet occur mostly below 120km. When the sun is “stormy”, red colours occurs at altitudes of 90 to 100km. Entirely red Northern lights may sometimes be seen, particularly at low altitudes.

The different colours of aurora at different altitude relates to the varying composition of the earths atmosphere and its decreasing density moving away from the surface.

Auroras of different planets:

Earth’s Aurora:

The resulting ionization and excitation of atmospheric constituents emits light of varying colour and complexity. The form of aurora, occurring within  bands around both the polar region.

Jupiter Aurora:

Jupiter’s main Auroral ring maintains a constant size. This is due to its formation through interaction within its own magnetic environment. Jupiter’s moon are also believed to be able to influence auroras.

Saturn Aurora:

On Saturn, the strongest auroras are in the UV and infrared bands of the spectrum and so would not visible to the human eye. But weaker pink and purple auroras have also been spotted.

Venus Aurora:

Astronomers love a good mystery, and here’s one they’ve pondered for decades. That is, Venus may have green auroras despite the fact it has no magnetic field of its own.

Mars Aurora:

 On Mars, aurora appear near areas of magnetised rock within the planet’s crust rather than near the poles, when charged solar particles concentrate towards them. This type of aurora formation is totally unique to mars as far as scientists are aware.

Summary:

Witnessing an aurora first hand is a truly awe-inspiring experience. The natural beauty of the northern or southern lights captures the public imagination unlike any other aspect of space weather. But auroras aren’t unique to Earth and can be seen on several other planets in our solar system.

An Aurora is the impressive end result of series of events that starts at the sun. The sun constantly emits a stream of charged particles known as the solar wind into the depths of the solar system. When these particles reach a planet, such as Earth, Jupiter, they interact with the magnetic field surrounding it, compressing the field into a teardrop shape and transferring energy to it.

Because of the way the lines of a magnetic field can change, the charged particles inside the magnetosphere can then be accelerated into the upper atmosphere. Here they collide with molecules such as nitrogen and oxygen, giving off energy in the form of light. This creates a ribbon of colour that can be seen across the sky close to the planet’s magnetic north and south poles- this is the Aurora.

SUBMITTED BY:

Priyalatha .M.

Ramyashri.

Preethi.

Sahana Rao L.N.

1st M.Sc. (2^ndSemester)     

SUBMITTED ON: 10^th April 2019

REFERENCE:

Internet

Journal

Edible electronics: A joke or cure?

Ready to Digest?

Implantable and ingestible (edible) electronic devices that stay inside your body pose unique engineering challenges. These should not only use the best processor but also be minimal in size, bio-compatible, safe and extremely reliable. Reliability is all the more important as it often turns out to be a case of life or death!

Despite so many risks and challenges, is awesome to see how implants have developed since the days of the first pacemaker in 1958. From cardiac pacemakers to cochlear implants, from brain interfaces to retinal implants, there are numerous implantable medical electronic devices available today. Even more exciting is the emerging field of edibles-tiny, capsule-sized electronic devices that consumed orally for diagnosis and treatment of diseases. Some edibles are designed to remain inside the body for some time, while others do their job and get disposed of within minutes.

Today, we have reached a state where inventions like these no longer surprise us because our minds have become tuned to a sci-fi future, and we have started expecting such developments. so lets put wow factor, and instead look; at the current and future state of implants and edibles.

Painless diabetes testing, drug delivery and more

With improvements in quality and reliability, there is now a reasonably good demand for cochlear, retinal and cardiovascular implants. Cardiovascular implants have evolved much in recent years, and have overcome past constraints regarding compatibility with imaging systems such as magnetic resonance imaging (MRN). Interestingly the rise in lifestyle diseases like diabetes as also led to an increased demand for implantable devices like implantable continuous glucose monitoring and implantable infusion pumps. There are also implantable devices for phrenic nerve stimulation to restore breathing function in patients, and sacral nerve stimulation for patients with bladder disorders. Implantable neuro-stimulators, on the hand help those with neurological disorders like Parkinson's disease.

With the availability of better bio compatible materials that minimize the possibility of infections, there is greater faith in implants. Researchers at Graem Clark Institute have developed an implant that is fitted under the scalp to diagnose and treat epilepsy.

Cochlear implants are used when hearing aids don’t work well- that is, when the patient has severe sensor neural hearing loss due to absent or reduced cochlear hair cell function.The implant basically carries out the function of cochlea or inner ear, stimulating the auditory nerve directly.

Retinal implants are giving vision to the impaired around the world. Going one step further, the Monash Vision Group is developing Gennaris – a bionic vision system that bypasses damage to the eye and optic nerve to restore functional vision for people who have injured both these or lost sight due to glaucoma and acquired retinal disease. This system interfaces directly with the brain, bypassing the retina and optic nerve.

Elsewhere, researchers are also exploring bio-compatible, implantable photonic devices that can improve health monitoring, diagnostics and light-activated therapies. Consider the possibility of bio-compatible and Wireless-powered light-emitting diodes (LEDs) and miniature lasers implanted inside the body. Advances in biotechnology, such as optogenetics, will enable these photonic implants to be integrated tightly with neurological or physiological circuits.

A good interface between implanted devices and the brain can help in great  ways the amputees and people paralyzed due to stroke or spinal cord injury.

A minimally invasive electrode called the Stentrode developed at the University of of Melbourne might be a step in this direction. Implanted into a blood vessel adjoining the area of the brain that controls movement, it may help control an exoskeleton, enabling crippled or paralyzed people to move. The implant can apparently be installed without opening the skull, which is what makes it attractive!

Neuralink, a company funded by Elon Musk, is also working on implantable brain-computer interfaces. They are developing syringe-injectable, flexible, sub-micron-thickness substrates that can be used in implantable electronics. The substrate is soft enough to sit harmlessly in the brain, and has electrical properties that enable only the  part at the brain to receive the electrical stimulus.

Brain computer interface is the future of implantable systems. It can help people with degenerative brain diseases and neurological disorders. However, it must be handled with care because an electrode implanted in the brain can be used both for good bad purposes!

Rise of edibles for diagnostics and drug delivery

When the electronic device needs to stay inside the body forever or for a reasonably long time, it is worth operating on a patient to implant the device. However, if you just want it to stay inside for a few minutes, hours or even days, for the purpose of monitoring a health condition or temporarily dispensing some medicines, operating on the patient doesn’t make sense. This requirement led to the development of ingestible, or edible electronics, which industry-watchers expect to create huge waves like wearables did.

The electronics that you swallow, encapsulate in a pill, will sit in your gastrointestinal tract for a short time, before being ejected from your body like regular food waste. During this time it can capture videos, release drugs, monitor heart rate and respiration, and perform other such tasks.

Proteus Digital Health was one of the pioneers in ingestible tech, And their technology is now used commercially by close to ten health systems. Their solution comprises a pill, a patch that is attached outside to the side of the stomach, and a mobile app/desktop portal. The pill is made of whatever drugs are required, and fitted with a sensor made of natural, ingestible materials like copper, magnesium and silicon. When a patient swallows the pill, it dissolves like a normal pill in the stomach but leaves behind a sensor, which is activated by fluids in the body. This sensor sends a signal to the patch, which also measures heart rate, body position and time of medication. This information is sent to the patient’s or doctor’s mobile phone. Regular drug intake is very important for those undergoing complex medical treatments such as organ transplants. This pill could be very useful for such patients. Proteus has teamed up with Tokyo-based firm Otsuka to embed Proteus’ sensors into Abilify-—a drug used for serious mental illnesses.

Another forerunner in the space is Israel-based Given Imaging. Their PillCam series comprises pills with ingestible cameras, which can help doctors to view different parts of the patient’s digestive system like the oesophagus or colon. It is a painless alternative to tests like endoscopy and colonoscopy. The PillCam Colon, for instance, uses a battery-powered camera to take high-speed photos as it slowly goes down the intestinal tract over a time period of eight hours. The images are transmitted to a recording device worn around the patient’s waist and later reviewed by a doctor. Although the images are not as sharp as those obtained through normal colonoscopy, it is a viable alternative for those who cannot bear the pain or feel embarrassed by the procedure. Other versions of PillCam help doctors to see the small intestine and oesophagus. The company has also developed Smart Pill - ingestible capsule that measures pressure, pH and as it travels through  gastrointestinal path. This helps doctors to assess Gl motility.

Bravo pH is another capsule-based test that helps to test for acid reflux. The miniature pH capsule attaches to the oesophagus and sends pH data  wirelessly to a small recorder worn on a shoulder strap or waistband. Information is collected over multiple days, enabling doctors to study the frequency and duration of acid flowing back up into the oesophagus. This helps confirm the presence of gastroe sophageal reflux disease (GERD). This is a totally catheter free solution, so the patients can go about normal activities and have a normal diet while the pill unobtrusively monitors their acid reflux“ They can remove the receiver to take a shower. This type of monitoring under a normal routine gives better results than keeping the patient under observation.

Parts of Ingestible electronics- overview

Powering

Main challenge: sustained powering bio-compatibility

Status: Limited to short and one time use. Large batteries are main cause of size consists of ingestible electronics

Outlook: Enegy harvesting concepts, novel materials for batteries and remote powering.

Communication

Main challenge: in-body path loss of RF signals, translating in high energy consumption and space requirements.

Status: transmitted signals are collected using body-worn receivers and systems are equipped with spatially demanding antennae and powering elements

Outlook: non-RF approaches, different antennae designs and materials, and alternative transmission approaches.

Interaction and steering

Main challenge: Localization

Status: Various concepts including biopsy drug delivery, steering and insufflation, have been demonstrated in capsule form but have not reached clinic

Outlook: Different capsule design to meet current standard of care.

Sensing

Main challenge: sensor fouling and limited versatility.

Status: Concepts are limited to systems that can withstand the caustic environment in the GI tract

Outlook: Downsizing of sensing concepts with adaption to special requirements of the GI tract.

Safety

Main challenge: Obstruction of GI tract

Status: Size limitations known from retrospective data on drug delivery system (Pill-shaped geometry)

Outlook: different geometries and self-disassembling or edible systems.

Eat your robot

We have bio compatible materials as well as transistors, sensors, batteries, electrodes and capacitors made using such materials. So you might think, why not a robot, too? But, what sets a robot apart from other computing systems is its ability to move-a robot needs an actuator, and attempts at making an edible one have been unpalatable all along!

Switzerland-based research organization EPFL has made some headway recently. At a conference held this year, researchers led by Dario Floreano presented the prototype of a completely edible, soft, pneumatic actuator made of gelatin glycerin and water. The design and performance of this new gelatin actuator is comparable to standard pneumatic actuators. Its structure causes it to bend when inflated and straighten out again when pressure is reduced. The main benefits are that it is edible, biodegradable, bio-compatible and environmentally sustainable. Since gelatin is melty, the actuator also turns out to be self-healing!

The researchers explain several exciting applications for this actuator. The components of such edible robots could be mixed with nutrients or pharmaceutical components to improve healing, digestion and metabolism. These can be used as disposable robots to explore, study the behavior of wild animals, cure sick animals or train protected animals to hunt. These can also be used in relief measures. In search-and-rescue operations, the robot can be sent without a payload to stranded people as the robot itself is food!

But we pay the bills?

A recent Frost & Sullivan report noted that the fastest growing segment amongst the my types of implants is implantable neuro-stimulators, which help treat neurological disorders such as epilepsy, dementia, Alzheimer’s disease, Parkinson's disease and dystonia. It is also likely that in the future, these implantable electronics will be digitally connected to improve the scope of remote drug delivery, testing and diagnostics.

The cost of researching and developing implants continues to be high due to the criticality and complications involved-and often this cost reflects in the end price points. In the report, Frost & Sullivan industry analyst Bhargav Rajan noted that the constant stream of innovations has attracted substantial private funding to the implantable electronics market, while public funding is expected to improve in the future. He also suggested that technology developers can lower development costs by collaborating with early-stage start-ups and small- and medium-sized enterprises. This will allow them access to cross-industry expertise and cutting-edge innovations, which, in turn, will help lower the price points. 

A majority of the population seeking implants belongs to low- and middle-income groups. Taking note of this factor, the report also stressed that the growth of this sector depends not entirely on technological development but also the availability of insurance coverage and reimbursements for such devices.

Laser tattooing

Scientists transform the surface of common materials into a nontoxic base for electronics and this enables scientists to put electronic sensors on everyday items.

Yieu Chyan is a chemist at Rice University in Houston, Texas. His team uses lasers to convert carbon in the very topmost layer of different items into an incredibly useful material called graphene(GRAA-feen). It’s a single-atom-thick layer of carbon. The researchers are perfecting their tattooing technique for use on common carbon-containing materials. These include paper, cork, wood, cardboard, cloth — even foods such as potatoes and toast!

The way that carbon atoms are arranged makes graphene appear black, so tattoos created with the laser can look like drawings. But the researchers don’t add ink or anything else to the surface. The graphene forms from carbon atoms that were already part of the material.

Graphene has a honeycomb-shaped structure and is arranged in sheets just one atom thick. As a laser passes over some material’s surface, its intense energy locks together those carbon atoms on the surface, turning them into graphene. Sometimes, the laser instead jumbles up the carbon atoms. This creates a foam, which has no structure. When this happens, the researchers pass the laser over the surface again. Its second pass converts the carbon foam into graphene. Scientists call the carbon treated in this way as laser-induced graphene, or LIG.

SUBMITTED BY:

Nirmal Mathew

Nithya K Nair

Poojashree V Rai

Prajna P S

Pramitha A

1st M.Sc. {1st Semester} 

SUBMITTED ON: 3^rd April 2019

REFERENCE:

Internet

Journals