Chhoti Si Baat..

Here's one comedy really worth watching for...Although this wasn't the first time I was watching this movie, doing so after about six years was really worth it..At once it made me realize how much my perception has changed through time and how great a few of the classics have been....

The movie is from 1975, so the entire movie is in the Bombay of the '70s- a truly beautiful place to have lived in..
The movie revolves around a truly hopeless character, Arun(Amol Palekar), a great beauty, Prabha(Vidya Sinha), Arun's brash, pompous rival, Nagesh(Asrani) and Col. JNW Singh (Ashok Kumar). Right from the beginning, the movie displays a level of comedy that is mature and sensible; in simple words, far above the crap that is churned out of bollywood these days..
Arun is in deep love with prabha, from the first time he sees her at the bus stop. In an attempt to make his moves, he follows her everyday till her workplace, keeps a good eye for her on almost everything she does. Prabha is one smart woman who has the perfect idea of what arun is doing. But she just enjoys watching him do his antics and waits for his first move...
One fine day, they do get to talking and develop an acquaintance. So the first step having moved to, Arun seems happy, but then enters Nagesh, who makes it difficult for Arun to even get Prabha's attention to him. In need of help, Arun turns to Col. Julius Nagendranath Wilfred Singh who helps the helpless ones in love. His interaction with JNW favours Arun very much and now a new, confident arun returns to woo Prabha.
The movie has some of the most pleasant songs of the '70s. The comic scenes are some of the best. Notable ones are Arun's daily routine, his day dreams and his lessons with JNW. Prabha demonstrates a brilliant example of how beauty is timeless. The '70s Bombay is a true marvel; BEST buses, the areas around V.T. and Mantralaya..It proves to be the Kohinoor for the nostalgic.

TATA Power

I guess I'm strangely lucky this week...although the pile of work has reached the neck, I'm spending some time here. Today we had an industrial visit to a TATA Power generating plant and boy!!! was it great! this one was better than our last visit, which was to the nuclear reactor at Tarapur. So..her goes..

It wasn't difficult getting there; a simple bus ride from the college to Chembur and then another one to Mahol. Mahol happens to be a truly vast industrial area...en route to the plant we saw many other industries, most of them being petroleum refineries. We were guided around the plant by a pretty nice guy (Mr.N) who had a sound knowledge of power systems; after all, he had spent ten years there! The plant has been in the power scenario of Mumbai for over 60 years and has been a pioneer in a number of advances in the generation and transmission sector; they were the first to have a 500 MW plant in the country, that too, with an efficiency of about 38.5%(thermal). They're having one of the most efficient thermal plants in the country, a 120 MW with an efficiency of 50%. They've also been the first to have three-phase four conductor transmission towers..and they're still going on pretty well.

We began with a presentation about the plant; that's from where I got all the above mentioned stuff. This was followed by a trip to the photo gallery where the entire history of the plant was put in pictures, right from the first newspaper article about the TATAs entering into the power sector to the installation pictures of the turbine and generator room and all. Mr.N took turns explaining the models of the plants to batches of students. The best part came when we were taken to the actual control rooms. The real-time monitoring of the plant by SCADA systems was great, so was a screen showing the boiler internals. Most of the controls were almost parallel to what we saw at Tarapur; screens showing the temperature at various points of the boiler, the monitoring of the transformers, cables and what not!

Something that I can only describe as 'better than the best' was peeping inside the boiler to get a glimpse of the actual heart of the reactor-a huge sun-like ball of fire (this is were tis IV took the lead over the previous one). The small window we peeped through looked like Balrog's(from Lord Of the Rings) mouth; I later came to know that was at 1200 C!!. The plant has to maintain a negative pressure within the boiler; this basically means having a low pressure within the boiler so that the hot gases remain concentrated within a region. The water is circulated in helical pipes around the boiler so that a uniform heating is provided to the water within. The turbine section in itself was a marvel. This was the second turbine I've seen in my life; I don't have a clear picture of the first one I saw at Kadambarai a long time back.

The rest of the plant wasn't much exciting and the visit ended quickly. I think we missed some parts owing to some maintenance work. But the fascination of seeing equations come to reality, the glowing ball of fire, and many other things we saw aren't images that would get erased. Thank God that this company comes to our college; even if I were offered the job of a cleaner, I'd consider it...

Pheezix

Well..I've been lucky this week...for I've been able to spare a sum total of 45 minutes for blogging!!! Never mind my schedule, this post is dedicated to one of my teachers who takes pheezix(physics) for us...at the very beginning, this post is not to libel her in any way, but just make some harmless little fun of her, something, which I believe every student has done in his/her life at least once...

Delores Umbridge (name changed for obvious reasons) happened to enter our institute early this year; so she has already taught us something. This is to say that we aren't absolutely new to her or to her teaching methodologies. When she was teaching us the principles of Digital Logic, last semester, we all had the impression of her being a woman who was an exponent in singing lullabies...for she did get the entire class(of 74 students) to sleep on almost all her lectures. But, that was just a part of what she had in store for us..

This time, she entered the scene with physics in her hands and believe me...so far, hell has broken loose quite a number of times...how? check this out...(this might be a little dirty, but it's reality)

Did you know that shit can have charge? that it can be a very good conductor and have the corresponding electric field and potential?? By the way, we must've been the first to calculate the electric field due to infinite shit..(if you haven't realized, she was referring to 'sheet' and not shit like how it sounds..)

Further, we were told that the distance of a point from the origin can also be negative..

Did you know that the dot product of two vectors can give us a vector as well?

Formulae, which took decades to shape up by brilliant minds, are of your making in this class; depending on your aesthetic sense, you can create as many formulae as you want....I guess, everyone from Newton's time must have turned in his grave a good number of times!!!

The other day, she says to the four of us,"come to me with notebook and pain"!! Once again, if you haven't got what it means, she was referring to a pen....All the garbage of the same kind has been flooding our classroom ever since her session began.
But, on a serious note, D does take efforts, and that too, sincerely at that. She does a good amount of study for the class and, to be honest, she doesn't always spew crap..only once in every three lectures. The problem is, despite her commendable efforts, she fails to get the message across the students' brains; astonishingly, she does so in an effort to explain each word...

Now, with the semester fast moving to its end, I wonder what more is coming along the way........some thing like relativistic shit??..

Coolie..

blogging is pretty difficult these days...going by the way our beloved college's piling the work on us. Anyways..I did get some time to see one of the very good 'comedies' of the 1980s..Coolie. Yeah..you guessed it right, the Big B starer. May be director Manmohan Desai did plan a serious venture, but me and my family here found it pretty funny to see out of the world things happen. For example:

A falcon (Big B's pet) always enters the scene from god knows where to come and spoil the villain's plans. The poor fellow has no choice but to look around helplessly(despite having all weapons to take care of that damned bird) till it comes and does good with his eyes!!!(boy what an eye popper!!!!) My apologies on not posting any pictures here..will try for them in the next post...

The characters in the movie are all related to one another through some means...like some orphan child happens to be one principal character's son and so on..you know..the stereotypical Bollywood stuff..funny enough..

This happens to be one of those movies where the show the incredible punctuality of the reel cops!! and the fools, they arrive in time only to arrest the only hot chick in the movie!!! how dumb!!!

We return to our friend, The Falcon here who truly has a great life span, does every thing that a man can do...like pick up a gun, almost talk to Big B..spot the baddie all alone and pluck out his eyes, get out of a closed car on its own..and what not!!! it was a treat to watch such marvels!!! Now, I'm considering getting one myself...may be it'll help me finish my assignments off!!!!!

Besides the comic part of the movie...it had a strong sense of Communism and a strongly echoing message of communal harmony throughout...I guess some of those Left parties might've considered putting the falcon as their party mascot or something...dunno why the didn't do it...

At the end of the movie..Big B gets shot thrice in his chest from a revolver at point blank range and still the Godly Docs at Bollywood manage to save him..sounds some what parallel to a few of those Tamil movies where the lead hero can die only if he chooses to!!!! For example..in the recent movie Sivaji, Rajnikanth gets a decent shock from a 440 V supply, he's given a few shock pulses into his heart after a few hours and he zooms back to life with that heavily accented "cool" on his lips!!

At the end of the day...no matter how much unexpected be a movie's outcome...as long as its from bollywood...it still provides entertainment in some form...be it a serious story with comic outcomes or cheap comedies or those in which only the feminine element is worth watching..

The same paper continued....

Translational Halbach arrays:

A Halbach array is a special arrangement of permanent magnets which augments the magnetic field on one side of the device while cancelling the field to near zero on the other side. In the diagram, the magnetic field is enhanced on the bottom side and cancelled on the top side (a one-sided flux).

The pattern (on the front face; left, up, right, down) of permanent magnets can be continued indefinitely and have the same effect. It is roughly similar to many horseshoe magnets placed adjacent to each other, with alternating polarity.

Moving Halbach arrays over a conductor results in an induced current through the conductor and consequently an opposite magnetic field is created. At a particular threshold velocity the induced magnetic field is strong enough to cause levitation over a series of such conductors. These arrays can be placed in a stable configuration and then insatlled in the devices.

High frequency oscillating electromagnetic fields:

A conductor can be levitated over an electromagnet with a high frequency alternating current flowing through it, this causes most conductors to behave as diamagnets because of the eddy currents induced in it. As eddy cureents cause opposing fields to be genrated it results in repulsion of the conductor.

Applications:

Magnetic levitation transport is a form of transport system that suspends, guides and propels vehicles via electromagnetic force. Using this we can achieve great levels of riding comfort and also very high speeds- almost in the region of 500 to 600 kmph. This is mainly due to the fact that there is no friction encountered whatsoever as there is no mechanical contact between the vehicle and any other surface. Only resistance is provided by air which too can be minimised by proper aerodynamic design.

The high speed potential of maglevs could prove to be a major competiton for airline routes of shorter distances . The world's first commercial application of a high-speed maglev line is the IOS (initial operating segment) demonstration line in Shanghai that transports people 30 km (18.6 miles) to the airport in just 7 minutes 20 seconds (top speed of 431 km/h or 268 mph, average speed 250 km/h or 150 mph).

Maglev technology has very minor similarities with the existing train technology thus it has to be designed as separate transport systems.

Technology

As previously mentioned maglev technolgy works mainly on three types of supension, namely the EDS, EMS and Inductrack.

Inductrack

This technique has a load carrying ability that is dependent on the speed of the vehicle as it depends on currents induced in an electromagentic array by permanent magnets. The permanent magnets are installed in the cart horizontally for lift and vertically for stability. The array of conducting loops is in the track. The magnets and cart are unpowered except by the speed of the cart.

Inductrack uses Halbach arrays for stabilization. Halbach arrays are arrangements of permanent magnets that stabilize moving loops of wire without electronic stabilization. Halbach arrays were originally developed for beam guidance of particle accelerators. They also have a magnetic field on the track side only, thus reducing any potential effects on the passengers.

Lift and propulsion

Germany and Japan are foremost in maglev research, creating and testing several new designs. An example of one of the designs is: The train can be levitated by the repulsive and attractive forces of the like or unlike poles of the magnets rspectively. The train is propelled by a linear induction motor on the track or on the train or on both. Since a strong magnetic field is required, large coils are placed along the track which create the required field.

Stability

Since magnetic bearings using only electromagnets and permanent magnets are unstable, diamagnetic and superconducting magents are used for a stable levitation of the train. Some conventional designs electromagnets that have electronic stabilization. This system works by constantly measuring the bearing distance and adjusting the electromagnet current accordingly.

Magnet Weight

The weight of the large electromagnet is a major design issue. A very strong magnetic field is required to levitate a massive train, so conventional maglev research is using superconductor research for an efficient electromagnet.

Pros and cons of different technologies

Each implementation of the magnetic levitation principle for train-type travel involves advantages and disadvantages. Time will tell as to which principle, and whose implementation, wins out commercially.

Some good stuff..

Some time back I happened to write this technical paper for a competition at our institute; although it ain't any great piece of research, the topic is something which deeply interests me. So, here's some of it..

Magnetic Levitation also known as “Maglev” is the process or technique by which an object can be suspended or made to ‘hover’ over another object without any support barring magnetic fields. There is no physical contact between the objects. Gravity is defied using electromagnetic forces.

Stability

Very often, stability in magnetically levitated systems is difficult to attain; this is further proved by Earnshaw’s Theorem which states that a set of point charges cannot be maintained in a stationary equilibrium solely by the electrostatic interaction of the charges. A corollary of this theorem is that forces acting on an object in any combination of gravitational, electrostatic and magnetostatic fields will make the object’s position unstable. However this theorem can be violated by usage of diamagnetic materials and electronic stabilization.

Methods

There are many ways of obtaining magnetic levitation of which the commonly used ones are EMS - Servo stabilized electromagnetic suspension, EDS – Electrodynamic Suspension and Inductrack, they are used specially in Maglev Trains.

Mechanical Stabilization:

This is the simplest way to attain levitation; by using two magnets which are constrained along a single axis facing their like poles towards each other. This will act to levitate one magnet over the other.

Direct Diamagnetic Levitation:

A diamagnetic substance is one which repels a magnetic field. Earnshaw’s theorem is not applicable to diamagnets because their behaviour is completely opposite to that of normal magnets due to their low relative permeability. This method was predominantly used to levitate water and animals.

The condition for this is given by, B*dB/dZ = μ₀ρg/χ, where

χ - magnetic susceptibility

ρ - density of the material

g - local gravitational acceleration

μ₀ - permeability of free space

B - magnetic field

dB/dZ - rate of change of magnetic field along the vertical axis
Assuming ideal conditions along the z- direction of solenoid magnet:

Water levitates at: B*dB/dZ >> 1400 T^2/m

Graphite levitates at: B*dB/dZ >> 375 T^2/m

Superconductors and EDS:

Superconductors act as perfect diamagnets (μ_r = 0) due to Meissner Effect. For type-II Superconductors, the levitation is stabilized due to flux pinning. This method, also known as EDS(Electrodynamic Stabilization) is used in some magnetic levitation trains. In trains where the weight of the electromagnet is a major issue(a stronger field is required to levitate the huge mass of the train), superconductors are used for the electromagnet, since they can produce stronger fields for lesser weight.

Rotational Stabilization:

A magnet can be stabilized by spinning it in a radial field created by other magnets. Stability is guaranteed only as long as the rate of precession slows below a threshold value. This method was used in the Levitron toy.

Servo Stabilization EMS:

Dynamically stabilized levitation is achieved by measuring the position and path of the magnet being levitated and depending on the motion of the object adjusts the magnitude of the field. This is the principle which is responsible for the demonstrations of levitation where a electromagnet or a beam of light is used to record the position and velocity of the object and depending on the proximity of the object to the magnet the field is adjusted so as to maintain a constant distance. This is exactly what happens in the maglev trains where the locomotive wraps around the track and is pulled upward by magnets, which helps in maintaining a constant height above the track.

Rotating conductors beneath magnets:

This is based mainly on the concept of electromagnetism where a conductor when rotated in the field of another magnet has a current induced in it and this causes the magnet to be repelled, if the speed of rotation is sufficient enough it results in achieving levitation of the magnet.

(The main source for this paper was Wikipedia, I'd like to acknowledge it...)

Rest of the stuff in the next post....

Monsoon

"Hi Blogger! Yesterday we had the first rain showers throughout Mumbai. Initially when it began drizzling, I thought it was just another conventional rainfall in response to the overwhelming heat. But it wasn't so and it went on pouring for a few hours. As if offering a light and sound show, the rain god chose to hurl a few lightning bolts here as well, many of them being as bright as though it were the afternoon time! But despite all the fury the weather offers, there's some strange beauty in it; the scent of the rain drops falling on the hot earth, the wonderful sound of the thunder clap.."

"I really wanted a few of the bolts to have fallen on a few people I 'love so much'. I'm not sure if it really happened that way; it was highly improbable. Nonetheless, it was some entertainment mixed with terror. By the way, yesterday I got another confirmation of me being the greatest Silly-Mistake-Master of all time. Man! it feels like another feather in the cap!! There are many instances when I have been 'honoured' so far..Xth Boards, Xth boards, JEE 05 (this one was grand!), all the competitive exams to have followed it, all my engg exams so far....in short, all the better part of my academic career. I know I sound sarcastic, but I have no choice but to accept it. Solution? For silly mistakes? Now that's like asking a maestro when he's going to retire from the profession when he's at the very peak!!! Alright..to put it more seriously, yeah, there's a solution. I'll tell you more about it when I see it work. Till then, Bye!!"