#technothlon

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Meet The Heads

In late 2003, a small group of students decided to design and conduct an exam unlike any other. An exam that is as fun and interesting as it is logical. An exam that requires no special preparation and has no syllabus. An exam that motivated students to think out of the box.  And thus, Technothlon was born. The first edition was conducted successfully in 2004, with 200 students participating from Guwahati. Every year since, a small group of students, the heads, have been selected and given the task of not only conducting Technothlon the next year but also making it bigger and better in the process. Over the course of 12 years, with the hard work of several generations of Technothlon heads, Technothlon has grown to be Asia’s largest student organised exam. In fact, Technothlon 2016 saw the largest participation in prelims and the winner getting a trip to NASA’s AMES Research Centre, California, cementing its place as the Biggest Technothlon yet. However, as has been the tradition, in late September 2016, 6 sophomore students of IIT Guwahati were selected and given the task of making Technothlon bigger, and better than ever before.

So, how does it feel, being responsible for conducting Asia’s largest student organised exams? Let us find out from the heads of Technothlon ’17!

Q:Do you think Technothlon ’17 will be the biggest edition of Technothlon yet?

Pratyay Nigam: With a team of such dedicated and motivated juniors, I am sure Technothlon 2017 will be the biggest ever

Jitika Rajpoot: Yes, I know that this edition of Technothlon is going to be its biggest edition yet. We already have very high standards set by Technothlon '16, and we are all set to break all records once again

Vishak Regu: Definitely. This year as well, we have managed to get a guided trip to NASA as our Grand Prize. This will give us a huge boost in terms of registration. Also, we have a very motivated and hardworking team of city representatives. So, there is no doubt that this will be the biggest edition of Technothlon yet

Q: What according to you are the benchmarks you wish to accomplish with Technothlon 2017?

Likhita Konjeti:  Conduct more LEDs, conducting the biggest prelims yet and conducting mains at a very good level 

Udayraj Deshmukh: We are focusing on improving the quality more than the quantity. Thus our benchmark is to meet the quality needs in smoother conduction of Technothlon, certificate distribution and faster declaration of results, and not only the conducting the biggest techno yet.

Pratyay:  As a core team member of Technothlon 2016, we broke the record for maximum participation in any exam conducted by a student body. This year I hope to work more on improving the quality of Technothlon such that Prelims is much more fun and interesting than it ever was. By the way, questions won't get easier though

Q: Technothlon's FB page has crossed 50k likes, Congratulations on the same. What do you feel is the reason for the enormous popularity?

Vishak:  The credit goes to our very motivated team of freshers for making it happen. I think one of the biggest factors for Technothlon’s popularity is that the exam is so much fun. Aside from this, our team works very hard to keep the page filled with interesting content, such as blogs, Techno Coup D’oeil and Factechs

Yash Gandhe:  Technothlon is known primarily for the complexity of the questions. Every year, each head tries to better the elegance of the same and this has probably led to us reaching a new milestone, the milestone being us reaching 50k likes on Facebook

Jitika:  The exam being completely logical, including no school syllabus is one of the very big reasons for its popularity. It is also unique; students participate in teams of two to give the exam. The other reasons I believe are that this exam is conducted by students who have just passed out from school, so they know the interests of school students better and so paper of prelims and the events of mains are designed by them in a way that makes it even more attractive for school students

Udayraj:  Reasons for popularity? Everything that we release contributes to it i.e. Factechs, Techno coup d'oeil, LED, etc. Our branding team also works very hard for it. The website and the app also add to Technothlon's popularity

Q: Which was a better experience - being a part of Team Techno as a fresher and a city rep or as a team head?

Yash: Each of the positions is better in different aspects and the experience necessary to become an exceptional head

Likhita: I can’t compare the experiences because both of them are worth it in their own way. Being a city-rep I learnt how to talk to principals, how to convince them etc. I really miss those moments when we were frustrated with the number of registrations we were getting. As a team head, the scenario is entirely different. You have the power to implement things, have freshers under you, the feeling I get during meetings is different.

Jitika:  All these experiences are better than the others in their own ways. However, Techno as a whole is a once-in-a-lifetime experience. And I feel really lucky to have been a part of it and will always work for the betterment of Techno.

Pratyay: Every position has its perks. As a team member, I was responsible in designing the question paper as well as worked on Mains' Events. Being a head is one hell of a responsibility, the six of us are responsible for conducting the biggest student organized examination of the country, it gives us a feel that cannot be expressed in words and at the same time that is what keeps us going. For me, I would say being a City representative has been the best experience till now. Conducting Technothlon in my city for the first time, representing my institution in the city, talking to thousands of students, tens of presentations, getting 600 teams registered and then "The Day: 17th July'16" when all the students are attempting the prelims paper, scratching their heads as well as having fun and then getting reviews on the questions, it made all the effort put in by me and my team the entire year worth it

Q: What is the biggest problem you faced as the head of team techno? How did you overcome it?

Udayraj: Honestly, the biggest problem for me initially was about how to bond with others. As a fresher I was not so open. But then I learned it from our ex-heads and the other five heads, it took a little while but now I think I have a pretty good bonding with others in the team

Vishak: Initially, the biggest problem I faced was getting registrations from the south zone, as a few schools had a problem with giving registrations. However, since then, these problems have been sorted out. Other than this, as a team, we are yet to face a major crisis. And even if we do, with these five people by my side, I believe we’ll be more than capable of facing it

Q: What would you say has been your best moment as a part of Technothlon?

Udayraj:  For me, one of the best moments was when we conducted LED in a small school near IITG. Seeing the faces of happy children was one of the best memories

Likhita:  As a city rep, on the day of prelims when you look at around 1200 students who came for Technothlon, and see them having fun trying to solve questions, you feel satisfied that yes, this was worth all the effort I’ve put in. For me, that was the best moment

Yash:  After the conduction of the exam, parents coming up to you and congratulating you on the successful management of the exam and knowing that you played a part, no matter how small in it

Jitika: As a city representative, the day 17th July 2016 was the best day of my life. The feeling of satisfaction that came just after the completion of the exam was the best. Every faculty member, invigilator, and parents around in the school who came for the exam were all appreciating the efforts. Students praising the paper of techno and everything else on that day was awesome. Techno has given me many, many amazing moments but this one was really the best moment of my life till now

Heads, Technothlon ‘17!

Stay tuned for more interesting blogs!

[technothlon]

The Science Behind Reverse Swing

Image Courtesy: http://www.freeimages.co.uk/

In one of our previous blogs, we had discussed the science (more particularly aerodynamics) behind conventional swing bowling. Why conventional? Because there is another much more intriguing facet of swing bowling: The Reverse Swing. In this edition of the Technothlon’s SportScience blog series, we are going to delve into the science behind the art of reverse swing.

History

Though it is not clear who invented it but Pakistani pacer Sarfraz Nawaz is generally credited as one of the very first practitioners of reverse swing in international cricket. His ball swinging skills were later passed on to Imran Khan and even later to the deadly duo of Wasim Akram and Waqar Younis. It is said that during its inception techniques to reverse swing were a well-kept secret within the Pakistani team but now almost every other fast bowler can swing an old ball unconventionally.

What is reverse swing?

Conventionally swinging balls swing in the direction in which the seam is pointed. And it is worthwhile to keep in mind that the movement occurs during its flight. But a ball is said to reverse swing when it swings but not in the direction in which the seam is pointing. So if a conventional in-swinger reverses it will move away from the batsman (out-swing). 

Now, before proceeding any further, we need to get a few scientific terms clear.

Boundary layer: When a body is kept in a region of fluid flow a very thin layer of fluid molecules literally sticks to its surface and are stationary but as we move away from the surface the fluid layers gradually pick up speed to match the free stream velocity, the layers of fluid over which this happens is known as Boundary layer.

Turbulent and Laminar flow:

Laminar flow is a fluid flow in which the fluid layers move parallel to each other and do not cross each other. Any flow that is not laminar is termed turbulent.

How does it work?

Flow asymmetry past a ball is the key to producing any sideward movement. For a normally swinging ball, the asymmetry is created by the uneven and slightly protruding seam. The ball is released with the seam inclined at an angle of around 20 degrees to the initial line of flight, now if the velocity of the ball is great enough (but not too much, you’ll see why very soon) the boundary layer on the seam side turns turbulent but that on the opposite (non-seam) side remains laminar. Now the turbulent boundary layer (on the seam side) is rather good at sticking to the surface of the ball than its laminar brother (on the non-seam side). In other words, the laminar boundary layer separates earlier (or more upstream) than the turbulent one. This causes the flow behind the ball to be deflected towards the same side as the non-seam zone is facing. And this, by Newton’s Third Law, generates a sideways deflection force on the ball in the direction of the seam.

Figure 1: Schematic flow over a cricket ball for conventional swing. (Courtesy: An overview of cricket ball swing, Rabindra D. Mehta)

For the ball to swing effectively it is very important that the non-seam side remains as smooth and the seam as prominent as possible. That is why players are often seen to be polishing the ball on one side by rubbing it against their clothes. It has been experimentally observed that maximum side force is obtained at a velocity of 29-30 m/s (104.4 to 108 kmph), seam angle 20 degrees with the ball spinning backward at 11.4 rev/s. As you might have guessed the spin helps stabilize the seam (a wobbly seam hampers the effect of any kind of swing force). But if the velocity is increased further the sideward force decreases. The reason being that at higher velocities the boundary layer on the non-seam side transitions into being turbulent and hence the flow asymmetry decreases. At a certain velocity, even zero force is obtained! At even higher velocities we enter the regime of reverse swing.  

At these velocities the boundary layers on both the seam and non-seam sides are turbulent but on one side it still has to encounter the seam. This time the seam plays a seemingly curious role, it thickens and weakens the already turbulent layer making it more susceptible to separation than the thinner turbulent layer on the non-seam side. Loosely speaking, the extent of the turbulent boundary layer depends on the height of surface roughness and its quite an intuitive that a thicker layer would separate more easily. Flow asymmetry is created once again with the boundary layer on the seam side separating earlier (or more upstream), deflecting the flow towards the seam side and producing a sliding force away from the direction in which the seam is pointing. Fascinating still is the fact that a ball can reverse swing with the exact same grip and bowling action as a conventional swinger. This makes it even more difficult for a batsman to predict the trajectory of a ball.

Figure 2: Schematic flow over a cricket ball for reverse swing. (Courtesy: An overview of cricket ball swing, Rabindra D. Mehta) 

So is there any way to reverse swing a ball other than just increasing the bowling speed? Yes! Absolutely, all that we have to do is make the boundary layer on the non-seam side turbulent, and it turns out that surface roughness on the non-seam side plays a very important role in deciding the approximate lower limit of velocity for which the ball will turn.

It has been experimentally observed that a new ball will show significant reverse swing for velocities in excess of 130 Kmph but this figure decreases dramatically to around 108 Kmph for old, beaten up balls. Why? Because old balls are rough on their surfaces.

Ball Tampering and Swing

Bowlers have always paid a lot of attention to the physical (including surface) qualities of a ball and their effects on its behavior. But, unfortunately, there have been a number of recorded incidents in the history of the game where players have gone beyond the rules to modify and/or damage the ball so as to make it behave in the desired way.

For a ball swinging normally a prominent seam and a smooth non-seam surface facilitates the movement. The center of ball tampering controversy in the 1970s was players using Vaseline and sunscreen lotion to polish the surface of the ball when the only substances legally accepted for polishing are sweat and saliva. Other than that players are often spotted trying to raise the seam to make it more prominent and aid in the production of the quantum of movement. The reverse swing, on the other hand, has been notoriously associated with ball tampering allegations right from its inception. It was even thought of as an outcome attainable only through illegal ball tampering techniques. There are well-documented cases, dating back to the 1980s, of bowlers trying to make the ball rough by nicking or gouging its surface, rubbing it on the ground etc. They were essentially trying to make the ball rough to help produce swing at lower velocities.

But the thing to be really emphasized here is that reverse swing can be obtained without resorting to illegal handling of the ball. At the outset, the opening bowler should pick a less rough side of the new ball and continue to polish only that side during the course of play, when the other side has roughened enough reverse swing is obtained just by flipping the ball over so that the smooth surface now remains on the side of the seam.

It has been more than three decades since reverse swing was first observed in international cricket. And it has certainly come a long way from being a mysterious, clandestine and almost illegal affair to being called an example of aerodynamic beauty. Credits, once again, go to science.

Abhirikshma Nandi, Team Technothlon ‘17

[technothlon]

The Testudo Formation

 “Wars are not won by taking the enemy’s life..it is won by saving your own life”- Anonymous 

Mythology is full of wars whether it is Indian Mythology, Roman or Greek. The tales may differ but when it comes to war, the situation is the same. Save yourself until the end and the victory is yours. Armies used various formations during the wars to defend and attack the enemy using the available assets in the most efficient way. So here’s another blog in the mythological series which presents you the details of one of the best defensive war formations depicted in the Hindu and Roman Mythology: The Testudo/Tortoise formation.

Structure:

The Testudo Formation was a revolutionary battlefield formation in which the soldiers used their shields in an interlocking fashion, effectively creating a structure like the shell of a tortoise. In the formation, the soldiers aligned themselves into squares or rectangles aligning their shields to form a packed formation covered with shields on the front, the top, and the sides. The first row of the men in the front and the two sides would hold their shields from about the height of their shins to their eyes, so as to cover the formation’s front. The shields would be held in such a way that the formation is protected from all sides. The men in the back would place their shields over the heads to protect the formation from the above. Each soldier in the front row covers the left half of his own body with his shield and the right half of the soldier on his left. The soldier behind him uses his shield as a lid to cover himself and the soldier in front. Each warrior uses the space between his own shield and the one next to him to hold out his long spear. This formation provided solid defense, much like the shell protects a tortoise, but could also be used as a devastatingly offensive battering ram with long spears bearing in on the enemy.

Tactical Analysis:

“It is so marvelously strong that men can walk upon it, and whenever they come to a narrow ravine, even horses and vehicles can be driven over it” - Cassius Dio, Author of “The Book of Roman History” on the Testudo formation

The Testudo formation was used to protect soldiers from all types of projectile attacks. This formation was very strong and could withstand a large amount of force. Hence it was used to defend the army while fighting a large enemy and hurting them without having significant casualties on your own side. This formation was also used to break the gates or give support to the soldiers for climbing the walls of a fort. The formation relied upon the training of the unit as individuals and as a whole. The testudo formation was cutting edge for its time as there didn’t exist any other organized army element with this much cohesion and level of training.

         A variation of the tortoise formation used primarily by the Spartans

The only disadvantage of this formation lied in its mobility. Seeing that all soldiers were required to move in unison for maximum protection, the formation was about as fast as walking speeds.

Though it might seem to be invincible, it was not without its own shortcomings. This chink in the armor is at its rear. If attacked from behind, there is little that the soldiers can do. They are weighed down with heavy spears which pointed ahead. It is difficult to turn around quickly. Furthermore, there is no shield protection at the back of the formation.

 Also, if a soldier tries to turn backward, he will end up hitting his fellow soldier and weaken the front part of the formation thus opening the breach for the enemies from both sides. So, if an enemy were to get behind, he could attack the soldiers and rout them completely.

Ashutosh Kumar, Team Technothon ‘17

[technothlon]

The Fosbury Flop

Physics has greatly influenced the progress of most sports. There have been continual improvements in equipment for safety or performance as well as improvements in technique. The Fosbury Flop is a good example of physics helping improve the performances of the sport significantly. The Fosbury Flop is a technique used by athletes in High Jump and is named after Dick Fosbury who won gold in the 1968 Olympics held in Mexico. This is the most used technique in High Jump nowadays. The secret to the effectiveness of the Fosbury Flop lies in the center of mass of the athlete being located below the bar during the jump.

The Center of Mass(CoM) of a body is the average position of all its mass by taking into account how the mass is spread around the object. For instance, the center of mass of a rectangular piece of metal lies at the intersection of the diagonals. Similarly, the CoM of a disc lies at its center.

The CoM of a person standing normally is somewhere around the belly. But this shifts upwards if the person raises his arms. So the CoM of a person varies continuously throughout the day as he performs various tasks. But it is important to note that the CoM need not lie within the boundary of the body itself. The CoM of a boomerang lies outside the body as well as the doughnuts.(see Figure below)

The Fosbury Flop takes advantage of this. So during the jump, at the peak, the athlete’s body is shaped like an arc similar to that of a boomerang. 

At this position, the center of mass of the athlete is located below the bar. You might be wondering how the center of mass falling below the bar helps improve the jump.

The answer is simple. Since the CoM is now at a lesser distance from the ground, lesser force is required by the athlete to lift his body. He thus expends lesser energy in a Fosbury Flop compared to a jump of same height using another technique. 

To perform this jump, use a ‘J’ shaped run-up approaching the bar perpendicularly in the first three to five strides. The Flop style of high jump is characterized by (at least) the final four or five steps being run in a curve, allowing the athlete to lean into his or her turn, away from the bar. Unlike the traditional style of jumping, where the athlete jumps with his face/body facing the bar, he jumps the other way around with his back facing the bar. Additionally, on take-off the sudden move from inward lean to outwards produces a rotation of the jumper's body along the axis of the bar, aiding clearance.

Combined with the rotation around the jumper's vertical axis produced by the drive leg (think of an ice skater spinning round on the spot) the resulting body position on bar clearance is laid out supine(lying face upwards) with the body at ninety degrees to the bar with the head and shoulders crossing the bar before the trunk and legs. This gives the Flop its characteristic "backwards over the bar" appearance, with the athlete landing on the mat on his shoulders and back.

But it is important to note that the Fosbury flop was not a feasible technique back when the landing pits were filled with sand softened with wood shavings. Earlier, the straddle technique was a better option for the athletes taking into factor the high probability of being injured by utilizing the Fosbury Flop. Later on, when the landing pits were cushioned with nice thick foam, the flop became feasible. Another factor contributing to the popularity of the Flop among the athletes is the ease in learning the flop compared to the other techniques. 

To sum up, the high jump competition, along with many other sports, is being exploited by physics!

Varun Seshadri, Team Technothlon ‘17

[technothlon]

Mythological Weapons

Hindu mythology is made out of numerous traditional narratives such as  Vedas, Upanishads, Puranas and epics like Mahabharata and Ramayana. All these books contain descriptions of gods, demons, sages, kingdoms, wars, religious practices, rituals, and spells. In this blog, we try and explain scientifically the working of some of these mythological weapons. For magic is but science we don’t fully understand yet.

The Narayanastra:

The Myth: It is said that the Narayanastra fires a powerful outburst of millions of deadly missiles simultaneously. The intensity of the shower increases with the increase in resistance. The only way to defend yourself is to show total submission before the missiles hit. This, in turn, will cause this weapon to stop and spare the target.

Ashwathama used this weapon against the Pandavas in the battle of Kurukshetra. To escape from this weapon Lord Krishna advised Pandavas and their army to drop their weapons and lie down on the ground, in such a way that they all surrender completely to the power of the weapon. Pandavas did so and survived the Narayanastra

Is it possible? Yes, building a weapon of this nature is possible. For fully understanding how it is possible however, one must leave the conventional image of an Astra being maces or arrows behind.

The Narayanastra could be a whole network of missiles. Not one, not two, but literally hundreds, maybe even thousands of missiles connected to each other. Sounds a little impossible? It’s absolutely practical. Almost all developed countries have similar underwater/underground missile systems.

Then how does the increase in resistance increase the intensity of the showers? We know that automation of things is not a dream anymore.Today we have Artificially Intelligent robots which can detect our mood or state of mind by our posture, heart rate, body temperature and facial expressions. The Narayanastra could have been an Artificially Intelligent defense system whose primary objective was the defend the empire, not attack.  The weapon would judge the state of the enemy (whether he is in a state of war or peace) by observing aspects like:

1. Posture

2. What they are holding?

3. Their facial expressions

4.Their heart rate.

If the system found the enemy in the state of peace it would retract. Whereas if the missiles found them to be in a state of war, the system would deploy even more missiles than before.

The Vajra:

The myth: The Vajra is Lord Indra’s weapon. It is said to be as strong as a diamond and is said to have had the power of a million thunderbolts. The weapon is said to have been made from the bones of the sage Dadhichi. The Hindu mythology goes on to state that the weapon was designed specially to destroy an asura named Vritara, who had received a boon that no weapon made of wood, nor metal could harm him.  It is one of the most powerful and feared weapons in the Hindu mythology.

Is it possible? Yes, it is. The Vajra could have been a huge, and extremely powerful electro-laser. To understand this fully, one must first understand exactly what an electro-laser is, and how it works.

The electro-laser is a directed energy weapon, which means that the weapon released highly focused energy which gets transferred to the target and damages it. In this case, the energy is in the form of electricity. As we already know, air is a very bad conductor of electricity. How then can one transfer electrical energy through the air? While air does not conduct electricity, Plasma, i.e, a new state of matter created by heating gas to extremely high temperatures around 5000℃, does conduct electricity. So initially, a high-powered laser is used to create a plasma channel from the weapon to the target, followed immediately by a high voltage electrical shock that is sent through the channel. The plasma channel lights up during the attack owing to the high electricity that’s passing through it, hence giving the appearance of thunder.

But why use bones instead of Iron or Wood? Simply put, the weapon concentrates electrical energy, and hence it could give rise to sparks and high temperatures. Wood would just burn, while Iron conducts electricity, which can harm the user as well. It is also interesting to note that Bones(3038 °F) have a higher melting point that Iron(2800.4°F).

Stay tuned for more interesting, and informative blogs!

Shubhansh Awasthi, Team Technothlon ‘17

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Register for Technothlon 2018 at MySchoolPage

Technothlon is a logic-based series of events held every year by IIT Guwahati, the leading educational institutes from India. MySchoolPage has officially joined hands with IIT Guwahati to bring this Technothlon international even to the Gulf countries this year.

MySchoolPage provides personalized, online home tuitions for students worldwide. They provide math online tuitions, science online tuitions, and personalized tuition classes for almost all the subjects in the students’ curriculum.

Being one of the leading educational startups in India, MySchoolPage also gives online Hindi tuitions, online English tuitions, bridge/fundamental courses, summer courses and more to school students. Their academic experts ensure that students get the best out of each online tuition sessions and solve their ncert mathematics problems, ncert solutions, igcse curriculum exams with ease.

MySchoolPage has opened its registration for Technothlon 2018, and its available for all students worldwide. Take part in the Technothlon Prelims - Hauts & Juniors, through MySchoolPage and stand a chance to win a free trip to NASA.

Register here for free to take part in the technothlon, 2018 prelims.

[technothlon]

The Science Behind Swing

India is a country of diverse cultures, languages, and beliefs. There are many schools of thought on each subject, a plethora of opinions on every matter. But one thing which has united us all for the better part of a century and still does is cricket. Cricket is not just a sport to the people of the country; it is something that transcends all religious and linguistic barriers. The sport has given immense joy to the people and the country takes pride in its prowess in the game. One of the key aspects of the game, which has been in existence for as long as the game itself, is the art of swing bowling.

The two essential aspects of cricket are batting and bowling. The sport has been graced with a multitude of great practitioners of the art of swing bowling. The great swing bowlers include the likes Wasim Akram, Imran Khan, Simon Jones, Zaheer khan and many more. It is an art which has taken years to develop and perfect and involves many intricacies in its execution. We will now see the science behind the art which was developed a hundred years back.

What is swing bowling?

Swing bowling is a technique used for bowling in the sport of cricket. Practitioners are known as swing bowlers. Swing bowling is generally classed as a subtype of fast bowling. The aim is to deviate the ball sideways as it moves through the air towards the batsman. The bowlers make changes to the ball in such a way that said deviation is produced. These physical changes produce a difference in the aerodynamics of the motion of the ball through air.

How does it work?

The principle is very simple - The ball when new has both sides shiny. Now the bowlers deliberately make one side a little rough and polish the other side. This makes the two sides contrasting. The asymmetry of the ball is encouraged by constantly polishing one side of the ball by members of the fielding team while allowing the opposite side to deteriorate through wear and tear. With time, this produces a marked difference in the aerodynamic properties of the two sides and results in a shiny side and a rough side. Fast bowlers prefer to swing the ball by making sure the seam is inclined at an angle of about 20 degrees to the direction that the ball is headed, in such a way that about 3/4 of the front of the ball is smooth. That way, the air flows smoothly around the smooth half but it becomes turbulent on the other side since it has to flow past the seam. Also, the rough side has more aerodynamic drag as compared to the smooth side, resulting in lower air velocity on the rough side. According to the Bernoulli’s principle, greater the velocity of air, lesser the pressure. Because of this, the shinier side has lesser air pressure hence more force will be exerted towards the shiny side.

Now when the ball is released, the rough side encounters high aerodynamic friction or also called as air drag and so the air pressure is high. On the other hand, the smooth side reduces the aerodynamic drag, hence less air pressure. Hence a pressure difference is created across the two surfaces of the ball.

Force is simply put, pressure times the area it is acting on. The pressure difference will create a net force which has a direction. This force created will make the ball move sideways. Since the rough side has higher pressure, a larger force acts on the rough side. This force acts on the surface of the rough side, and the net resultant force will be towards the shiny side. Hence the ball will move towards the shiny side creating the swinging motion of the ball. This type of swing is termed as contrast swing.

The above explanation works for an old ball with some wear and tear on it. But a new ball cannot be swung in this way. When the ball is new the seam is used to create a layer of turbulent air on one side of the ball, by angling it to one side and spinning the ball along the seam. Due to the seam being at an angle to the face of the ball, the air flow at the face is separated by the seam into a turbulent state above and a smooth flow below. This once again creates a pressure difference between the upper and lower faces which is responsible for a force which causes the ball to swing in the direction in which the seam is pointing (the turbulent side). This type of swing is termed as conventional swing.

These two methods are commonplace among swing bowlers today but it involves a much more complicated scientific background than one would have thought. This shows the extent to which science has affected sports and the role it plays in any game. This is only the tip of the iceberg when it comes to the scientific phenomenon involved in sports. Stay tuned to the Technothlon blog for more!

Jishnu Chander, Team Technothlon ‘17 

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CityReps Speak: Vamshi Krishna Reddy

Technothlon is driven by over 400  CityReps each year, each one has a different experience. Read on as Vamshi Krishna Reddy, City Representative of Karimnagar, Telangana shares his experiences with us. 

Q. I think we both agree that conducting an exam of this magnitude is quite amazing. And nothing great ever comes easy. What challenges did you face while conducting Technothlon in your city?

A. I would say my biggest problem was me, myself. I was well known for being silent and for my discipline in my school. I have faced a few scenarios which completely disturbed me and hurt me. For example, there were several instances where the teachers and administrators thought that I was doing this for profit. Comments like, “These guys have started early, very good field for profit” really hurt my self-respect because this was something I was doing to improve my skills, not make money. There were some schools which asked for 80:20 commission, some wanted an assurance that we will give them at least one rank in top 50. I had to explain to them clearly that Technothlon was a Non-Profit Organisation and that we don't make any money from this. And there were schools that I had to visit around 8-9 times just to convince the principal.

Q. Overcoming all these challenges, you must have definitely learned a lot. What do you take away from this experience?

A.Firstly, I have overcome stage fear and have learned to deal with people politely. My convincing skills have also improved a lot. There were some cases where the principals did not agree with what I said. I had to intelligently convince them using reverse/counter convincing skills. And I had to use totally different ways to present the same thing to the administration and to the students. In fact, I took 1h 45 mins for a presentation once, and not even one kid was sleepy after the presentation. They actually just asked me questions at the end. I also learned to be patient, because sometimes I had to talk with a person more than 8-9 times for an issue, and he would just say come and meet me later.

Q. How did it feel, overcoming all these challenges and successfully conducting an exam for over 1300 students?

A.  It was a great feeling. Actually, it gave me a lot of confidence, managing so many students at once.

Q.  Students are usually full of surprises, and conducting an exam of this magnitude and managing over 1300 students, you must have had some pretty interesting experiences. Any particular experience, either memorable or interesting, that you’d like to share?

A. Well, we had to deal with loads of cases where students filled the wrong mobile number or shaded the wrong bubbles in their OMRs. But most of my memorable experiences came during the planning and execution stages. With three of my friends, with whom I hadn’t even discussed my marks with before, so you can guess how little we knew each other, we completely made the seating arrangement for 1300 students in a five storeyed building within two hours, that too at 11 PM, the night before the exam.

And the best part was the invigilation in my city was done by two people in each room, a teacher and a friend. After the completion of the exam, the principal of the centre told me that even his staff can’t manage such a large crowd, how was Technothlon organized?

Q. How did your parents and relatives react when they got to know that you were conducting an exam of this scale?

A. At first, I thought they would scold me. But they were very supportive. They motivated me, branded Technothlon within the family, helped me get easy appointments with officials through their friend circle. Helping me in every possible way. And finally, they are very proud that their child is responsible for conducting an exam for over 1300 students.

Q. As you know, this year as well, Technothlon is going to be conducted by a whole new set of city reps. Is there anything you’d want to tell them?

A. The morning after the exam, i.e., the morning of 17th July 2017, you will realize for the first time exactly what Technothlon is, who you are, and what you have managed to pull off. So please be patient and do not judge Technothlon before that morning. 

Q. Any special mentions? Anyone you’d like to thank?

 A. I would like to thank Goli Sai Sharan, who didn’t even sleep for a single minute the night before the exam. Thanks to my parents, their colleagues for invigilation and dad for the media articles. I would also like to thank my Co-CityRep, Devansh, who was my motivation. Even when I said I am not interested in going to a particular school because of a comment the faculty passed on my last visit, he dragged me along.