tips for iit jee

The JEE Guide...

Well for those who do not happen to know me, I am Nitish Wagle, a 2nd year student of Mechanical engg. at IIT Bombay. I cleared IIT-JEE 2007 with an AIR of 411.

I write this text in an attempt to clear a few misconceptions about competitive exams. It has always been believed that JEE is meant for two kinds of student

• Students with a flawless academic record throughout their life

OR

• Students who take dedicated coaching in places like Kota for 2 or more years.

Well, I was neither. My academic record was far from perfect. I scored 81% in SSC and 71% in HSSC. My PCM in 12th std. read: - Physics-80, Chemistry-54(27/70 in theory) and Maths-67.
I did my HSSC from Goa with coaching from Aaryaan Study Circle (only in 12th std.). But still I managed to get through with a respectable rank and get admitted into the branch of my choice.

I am not telling you all this to boast off myself but just to make you understand that you need not really have extraordinary memory and academic excellence to clear the JEE. A good attitude can hide many of your flaws. At the same time I am very much sure that I didn’t even stand a chance at cracking the JEE if I were to answer it in subjective format.

Over the last couple of years many people, students and parents alike have been asking me what was the ‘Secret’ of my success. I have always felt that the key to my success lied in my attitude towards the competitive exams. That is why am writing this article,to try and help you to improve your attitude towards competitive exams.I have mentioned herein, some tricks that helped me in exams like JEE and AIEEE. All these tricks may not work with you because everyone has a different style of working. But I strongly feel that going through this short piece of text would be worth the effort (if I didn’t think so, I would never have bothered to write it). Do give it a try and use whatever you feel helps your style of studying and answering exams.

In no way do I wish to implicate my superiority over any of you through this text. I do not consider myself a teacher. This is just an effort to share some knowledge that helped me. I write this because I strongly feel that no books give enough significance to the right attitude toward competitive exams. I have learnt through my experience and that of my friends here at IIT that the attitude and answering techniques are just as important as all the theory you learn.

I would however, not advice you to take this text as authoritative. All the things here may or may not help you. But in case you do have time left before your exams, do give the techniques a try and see for yourself if they do any good. Best of luck and Happy studying...

The Right Attitude...

I have always failed to understand the negative attitude people have toward competitive exams, especially those following an Objective questions format. How do they fail to see that no matter what format an exam follows, every student answering it on the same platform. It is no tougher to get admission into the college of your preference through a CET as it is through board exams.


The problem is that people are too used to scoring very high percentages in board exams through extensive mugging up according to the predictable type of questions. They are afraid to explore into the unpredictable world of competitive exams. But what they fail to see is that the exam is equally unpredictable for every student answering it. And that this unpredictability can be turned into your favour if you have a better attitude towards the exam compared to the others. This attitude is what makes the difference between a good student and an achiever. This is what made the difference between me and many of my batch mates who were equally good and easily surpassed me in board exams but could not perform to their potential in the competitive tests.


It is very easy to develop a positive attitude towards competitive exams which have Multiple Choice Questions if you get the standard mentality out of your mind and consider the benefits of such an exam. The main benefit of a MCQ paper is that you cannot really blank out in the examination hall. In a subjective paper, if you do not know the answer to a certain question, there is not much you can really do about it. But in a MCQ paper, the answer is always in front of you. All you have to do is eliminate the wrong options and choose the right one. This may sound a bit absurd but once you change your outlook, you’ll see that it’s not all that difficult after all. There are quite a few ways to eliminate wrong options. We will talk about them later.


Another major misconception is regarding the negative marking. Many students are scared to answer a question with negative marking unless they are completely sure about it. What they do not understand is that by the laws of probability, they need not be exactly sure of the correct answer in order to answer the question. The normal marking scheme for questions with 4 options is +3 for a right answer and -1 for a wrong one. In this case, even if you do not have any clue about the correct answer and randomly choose any option, probability says that you will get 1 out of every 4 questions correct giving you 1x(+3) + 3x(-1) = 0 marks. So according to probability you wouldn’t lose any marks. But then, in almost every question, it is possible to eliminate at least 1 wrong option. This shifts the odds in your favour even if you take a wild guess amongst the 3 options remaining.


I answered all the questions in my JEE and AIEEE papers. I am not telling you to do the same. But if you are good enough at the technique of eliminating wrong options, there is no reason why you should not answer all the questions.


There are three ways of solving any MCQ:-

1. To actually solve the question by using formulae(if it is a numerical) or your memory(if it is memory based). And
2. To increase the probability of getting the right answer by eliminating as many options as possible.
3. To somehow get to the answer by using logic and approximations without actually following the conventional method.

Although the first method is preferred in most of the question, the 2nd method is just as important. Any student, no matter how brilliant, would never be able to remember all formulae and theory required to solve the questions.

There will always be quiet a few questions wherein you wont know what to do. This is where the 2nd method comes in. The 2nd method may not give you the answer for sure, but if you can eliminate even one of the options, you should just take a wild guess between the remaining options because the probability is always in your favour. In most of the questions, it is fairly simple to eliminate even 2 options, in which case you would have to choose between the remaining 2 putting the odds 3:1 in your favour. Once you get used to eliminating options efficiently, you may even be able to eliminate all 3 wrong options and hence solve the question for sure.


The 3rd method can help you to save a lot of time even when you do know the formulae and theory but know that it would take a long time to solve the question by conventional method (however you should not take this risk unless you are sure of your techniques or are very much short of time). With enough practice, you would be easily able to judge which of the 3 methods are supposed to be used to solve a particular question. Remember that I am not teaching you a ‘shortcut’ to get things done but am just teaching you techniques to make better usage of your knowledge and time.



To illustrate how effective these methods can be, let me share a few personal experiences:-


I did not have any knowledge of integration other than the fact that it is the opposite of differentiation. I could not have integrated any function which is not a direct differential of a simple function (like sin x, log x, etc.) without the options. Yet I was able to solve all the integration related questions in JEE and AIEEE. I am not encouraging you to neglect integration (I neglected it because I could not remember the different techniques due to my poor memory), I am just telling you how strong alternative methods can be.

I also did not know any trigonometric relations.
For eg. I could not even expand sin(x/2) But yet trigonometry was always my strong area due to the various techniques that can be used to solve those questions.


Although I was pretty good with physics, I often found that using a bit of logic made it possible to solve even the toughest questions in physics. This will however, need you to be very strong with your concepts. You should never look at questions in physics as numericals. They should always be viewed as concept based questions with numerical values thrown in. Just mugging up formulae will not help you to do well in physics in competitive exams. It is more important for you to know how and where the formulae are to be used and the correct sign convention. For this, your concepts should be very clear. You should know for sure which quantities can have a +ve value and which will have a –ve value. Many students make the mistake of blindly following a sign convention without knowing what it really means. This can really hurt you in confusing questions.


Although numerical techniques cannot normally be used in chemistry, you can often eliminate options by using a bit of logic. There are also quite a few memorizing techniques that would be of great help in organic and non-organic chemistry. It also helps a lot to focus properly on the syllabus of the exam and study accordingly. This helped me outperform other students who had much more knowledge of chemistry than me.




Let us now focus on some common techniques topic wise:-

MATHEMATICS

Algebra and Probability

The main technique to be used in probability is logic. In most of the questions you get from this topic it is possible to eliminate at least 1 wrong answer just because it is illogical. For eg. Sometimes you have an option that implies that the probability of a certain event is greater than 1 or less than zero, some options imply that the probability of a secondary event is more than that of the primary event these options are certainly incorrect (eg. The probability of a random student in a mixed class being a tall girl can never be greater than the probability of the student being a girl). In order to be able to find such contradictory options, you need to be clear with all the concepts of probability.

Another method is numerical substitution. This is very important in questions related to series, progressions, permutations, combinations, etc. You will often find question in algebra which do not involve any numerical value. For eg. Find the sum of the series Y(n) = n * (n+2) * (n+3) from n=1 to n=N in terms of N (**all questions given as examples are imaginary and may not have a proper answer). In this type of questions, you can easily find the value of Y(1), Y(2), Y(3). Now check which of the options give the same value for N=1, 2, 3. Whichever option does not give the same values is obviously wrong. You will almost certainly get the right answer by this technique. Note that you may sometimes have to evaluate till Y(4) or Y(5) or may also get the answer as early as Y(1) or Y(2). All you have to do is evaluate for N=1 and check, if all 3 wrong options are not eliminated, evaluate Y(2) and so on. This may sound a bit cumbersome but once you start using it, you will find it very easy and fast. Whenever you see any question which involves a general equation with 1 or 2 variables, try and see if you can eliminate wrong options by using simple numerical values. You have to be a bit cautious though not to make silly mistakes. But with proper practice, you will easily perfect this technique. This method can also be used in exponential equations of higher orders if you are good enough with numbers.


Trigonometry

This is the topic where I used numerical techniques to the highest extent. Almost all questions relating to generalized equations can be solved by putting actual values for the angles involved.

For this you only need to remember the basic ratios for standard angles like 0,30,45,60,90,etc. in decimal system and should be able to approximate the ratios for angles like 15,75,etc. this is very simple and I am sure that each and every one can do this. Now you can just replace the x or y in the given question with a suitable angle value, evaluate the value of the question and then try to match it with the values of different options. lets take a simple question:-

Q: Which of the following is equal to cos (A/2) :

a) cos (90- A) b) root of( tan A) c) root of ((1+cos A )/2) d) root of ((1-cos A)/2)

Now taking value of A=60 , we know that cos(60/2) = (root of 3)/2. Now put the value of A in all 4 options and you will find that only options a & c satisfy the equation. Hence b & d are discarded. Now put A=90. Now a does not satisfy the equation and is discarded. Hence c is the right answer.

Now you may say that this was a simple question and you already knew the answer from half angle formulae. But believe me, no matter how difficult the question is, it is very likely that you will get the answer by putting numerical values.



Differential calculus-

Well there is not much that can be done here. At least I did not use too many shortcuts because I found it simple enough to solve using conventional methods. You can however, sometimes eliminate a few options mostly based on the sign. By taking a few actual values, it can be found out whether a function is decreasing or increasing in a certain range. You can therefore judge the sign of the differential and hence discard the wrong options. I would however, not advice this method if you can actually differentiate the function and find the answer. In questions related to application of differential calculus, u can often discard question by use of simple logic.


Integral calculus-

As I stated before, I never studied integral calculus and hence had to completely depend upon special techniques to solve all the questions. If you are proficient with integral calculus, I would advice you to do it the conventional way. But if you do find some difficulty there are quite a few techniques that can be used. The most basic technique is to differentiate the options. This however, may not work in tough exams because the paper setters are normally cautious enough to set questions with options that cannot easily be differentiated to directly get the expression in the question. You will however, find a couple of questions that can be solved by doing this.

Another useful technique involves using definite integrals to find indefinite integrals. Herein you draw a rough graph for the equation in the question, approximate the area under that curve in a certain region (along with the sign) and then compare it to the value given by the various options in that region. Let me illustrate with an easy example:-

Q:Integral of sin^2 (x) {sine squared (x)} is :-

a) cos^2 (x) b) cos^3 (x) c) x/4 -1/2 sin(2x) d)x/2 – 1/4 sin(2x)

Now drawing an approximate graph of sin^2(x), u will notice that is can be approximated as a straight line between 0 and pi/2(note that value at pi/4 is ½ and at pi/2 is 1). Hence taking the area of the triangle A=1/2*(3.14/2)*1=1.79. now checking with the options you will see that only option d gives a similar value(in fact in this case it is the exact same value because of the property of sine function, this need not be the case always as we are approximating the triangle). We were lucky to find a near triangle, this need not always happen. But with adequate practice you will learn to approximate areas of different shapes. This process is much easier than it sound, especially once you get used to it. if you are having difficulty approximating the curve, there are other methods to eliminate a few options. in the given question, note that the equation in the question is always non-negative. Hence the definite integral should always be +ve as well. This way you can eliminate option a & b as they can have –ve values. Do always make sure you take angles in radians or degrees wherever appropriate in trigonometry based questions.


Analytical geometry-

The techniques used in this topic are a bit complicated to explain and I have also forgotten most of them. I would suggest you to develop your own techniques. One basic technique is to approximate the curves by taking some points. This method is difficult to really explain as it takes a lot of graphical imagination.

PHYSICS

Optics-

Many students find optics very confusing. The main reason for this is the confusion with sign convention. If you are perfect with the sign convention that you use, stick to it. But if you do find it confusing, there is one thing that can really help you- Using a bit of logic. First of all, get your concepts really clear. You should be able to tell (qualitatively) for every type of mirror or lens where the image would be formed for any position of the object and whether the image is real or virtual. Once you understand the physics behind formation of image by reflection/refraction of light, you will be able to solve any kind of question. Besides there are not too many different types of questions in optics so practicing different questions really helps as it is quite likely that you will get a similar question in the examination.


Mechanics-

I cant really think of any shortcuts in mechanics. All you need to do is get your free body diagrams in place. No matter how complicated a question is, if you can figure out all the forces and moments acting on the body, you can easily solve it. You can often eliminate options based on sign in mechanics as well as optics. For eg. Sometimes you just know that a certain quantity has to be +ve and 1 or 2 of the options have a –ve sign(or vice versa). This greatly increases the probability of getting the answer right even if you cannot solve for the numerical value. Also be solid with your dimensions because often dimensional analysis gives you clues about which formulae to use.


Electricity and magnetism-

Not too many shortcuts here either. Your concepts need to be really very, very clear to stand a chance at solving JEE level questions. Do not depend on formulae because when you face a really good question, you will not know which formula to use and where to use it. make it a habit to solve the questions, specially in electrostatic, step by step. Remember that all you need to solve the toughest of the questions are the basic laws of physics. All that you need to do is apply them step by step and without any mistakes. I would suggest you to devote a few days at a stretch only to this topic so that you get all your concepts clear. Also solve as many questions as possible. It will help you greatly to clear doubts and build confidence.

One basic technique that I find highly underused is symmetry. I fail to understand why students can’t think beyond the formulae and use symmetry. It is a very important property in many topics none as important as circuits. The basic principle is that two symmetric points will always be at the same potential and there is no current flow between them. This can greatly simplify many daunting questions. Symmetry can also be used to great effect in analytical geometry.




Modern physics-

This is a relatively simple topic as there are not too many concepts to remember. All you need to do is get a ‘feel’ for the different kind of questions.

CHEMISTRY

Physical chemistry-

Physical chemistry is very much similar to physics in terms of the right approach. You should always know (qualitatively) what can possibly happen and what cannot happen. For eg. You should know whether different quantities would increase or decrease on addition of a certain substance to a solution. This can be done by extensive reading and problem solving. It is of no good to simply mug up formulae, especially in topics like solutions, kinetic, electrochemistry, etc. unless you know how exactly to use them. It is a very common mistake by students to use the wrong formulae in such questions. Once again u really need to get a ‘feel’ of the topic. You should be able to imagine what really happens at the molecular level and how exactly properties change.


Organic chemistry-

Not too many shortcuts here. One advice I would give you is to write down all the chemical reactions given in the syllabus (not all individual reactions, just the general reaction) along with the exceptions and special features (if any) on a small note book and make sure you know all of them. Also try to imagine what exactly happens in each reaction at the molecular level. You need not know the detailed mechanism of every reaction but should at least know what roughly happens. Do not study too much out-of-syllabus stuff unless you are sure you can cope. JEE and AIEEE strictly sticks to the syllabus mentioned in the prospectus.


Inorganic chemistry-

This is a completely memory based topic. I would suggest you to try and enjoy reading this topic and avoid making it boring. Another great way to learn a major part of this topic is to understand the qualitative analysis that you do in the lab. If you can learn the logic behind the experiments conducted it would greatly help you understand the theory. Try and memorise colours of different compounds because colours are easy to remember and are frequently used in exams. Also try and find trends and funny facts in the text. This helps memorise the text even if you have a weak memory like me …


These are all the techniques I could think of.


The most important thing is that these techniques may or may not help you. I developed these myself because they suited my brain and my way of studying. They were designed to make as little use of memory as possible and rely heavily on numerical and analytical power. You may need to modify them according to your memory and numerical ability. Do try these out and try to modify them according to your needs. You may also develop techniques of your own which suit your needs.


The main aim behind this text is to help change students’ attitude toward competitive exams. So even if you do not find any of these techniques useful, do try and remove the mental block many students have about competitive exams. Make sure competitive exams become your forte. Unless you do that, you will never get the education of your choice no matter how well you do in boards and all.


One more studying technique I will really like to advocate is studying in a group. Find friends who complement your style of studying and try to share questions and ideas whenever possible. I am not telling you to always study in a big group or anything. But it is very healthy to discuss study related stuff with your friends regularly. It helps u check you progress, get new ideas, understand your mistakes and solve your doubts. That too in a fun way. So make sure you have at least a couple of study buddies.