 I am Gayathandey with Bandarkar and we will be discussing with you thermodynamics in mechanical engineering for the next week or so. And again we will continue to meet electronically till May-June when we will conduct a two week or a ten working day session. What you see here is a, I had said a tentative structure, a tentative timetable because I and we do not really know what we are involved during these five days. Our main aim is to make that two week program or that ten day program a proper success. We have taught thermodynamics a large number of times. I have been a faculty member here for over 30 years and may be more than 15 times I have taught the undergraduate course in thermodynamics. The course itself has gone through a number of modifications but the basic structure has more or less remained the same. I first taught it in 1982 and latest implementation was last semester and most of you have taught thermodynamics at least a few times. I notice someone has 22 or 25 years experience. I would not be surprised that he or she has taught thermodynamics about a dozen times. So generally we know what thermodynamics is about. So one thing we are not going to do is this is not a formal lecture course in thermodynamics. He said that this is, remember this TTT, what is meant by that, time, temperature, transformation curve. But as teachers I think I should go back, when I was an undergraduate there was no QIP program. The QIP program I think started in 1971 or so but there were a few college teachers from other colleges, they were here and they were known as TTTs. The TTT program was a predecessor or precursor of the QIP program. That TTT program was known as, it stood for technical teacher training program and I think at that time a few institutes were set up, maybe they are still there, they are known as TTTIs, technical teacher training institute I suppose. I do not know whether they still exist or not, one was somewhere in Bhopal, one was in Madras, one in Chandigarh but being in Mumbai I found that Bhopal and Madras were being talked about at that time. But also we have a TTT program, you can call train the teacher and there is also a formal talk to the teacher program. So we are going to do discussion on thermodynamics which is another T, so maybe train teachers in thermodynamics or teach teachers how to manage thermodynamics, you can take it like that. What you see here is the topic list of thermodynamics. I would like to spend up to 11 and then after 11 up to the lunch time on a preliminary discussion about what we are going to do. In your handout you will find a list of topics, a sort of a structure of the way we have been teaching or a reasonably neat course in undergraduate mechanical engineering thermodynamics is taught. When Professor Fatak requested me to start off or kick off the first non-CS course under this Eklavya scheme or whatever scheme that is there is an ISTE workshop then there is a national mission on education of teachers through in ICTs. Let us call this simply by the word Eklavya and that is why I have used the symbol Eklavya on your exercise sheets and others. He said there is a course called introduction to mechanical engineering in many, many colleges or basic mechanical engineering in many, many colleges why do not you teach that and he said why me? He said no a reasonable part of that is thermodynamics, you have been a good teacher of thermodynamics so why do not you do it. And we undertook a survey and we found that there is a difference in the way thermodynamics is treated as a basic undergraduate course in mechanical engineering. IIT is treated in a different ways, many colleges treat in a way similar to IIT but at many, many places it is split into portions and different portions are parceled off to different subjects and different papers. A very common theme seems to be a course in the first year called basic mechanical engineering or introduction to mechanical engineering which is part of a set of courses called introduction to x engineering where x can be replaced by mechanical, electrical, electronic, civil what have you and a typical student goes through about 6 such courses, 5 or 6 such courses in the first year so whether is a student of mechanical, electrical, civil introduction to mechanical engineering he will go through. And when we looked at the course content or the syllabus of curriculum we found that the Indian scheme of things seems to be syllabus is split into 6 units, typically 6 units I think that is true in most of the cases, okay let us not go into why those 6 units but that is the scheme of things so I said let me look at write down the typical units in some 40 or 50 colleges typically the list from where you have come across but not exactly and what I found is there are certain commonalities but if I take an intersection of all those 40 different syllabi I find that hardly 2 units are common and when I take a union I find there are I end up with something like 24 distinct units similar and slightly different units I have considered dissimilar so even I found that in the introduction to mechanical engineering there is no convergence so it would be very difficult to do that. Then I said that look rather than do a hodgepodge of things because introduction to mechanical engineering would contain not only thermodynamics some fluid mechanics, something of mechanism, something of power transmission, something about manufacturing everything under system. As it is mechanical engineering is a very vast field it is very difficult to say what mechanical engineering is not if you look at most of us are mechanical engineers so I can say it very loudly if you look at the engineering syllabus of various branches I think mechanical engineering syllabus is the most wide and even from the societal point of view the abilities expected of a mechanical engineer are among the widest of the abilities expected of any other engineer. So a mechanical engineer will shy away from saying that is not my job or I cannot do it I will get it done I will do part of it other parts I can get it done from my friends. So I said that look management people talk of core competence so what is my core competence thermal engineering within that thermodynamics. So let me do justice to thermodynamics itself and then I found that the way I have district the scheme of thermodynamics is more or less taught in almost all engineering colleges but may not be in one single course. So my first proposal to you is to go through that and assure yourself and tell me if a student in mechanical engineering does not learn these things these 13 major topics and of course more because we do not know where thermal engineering ends and hence where formally thermodynamics ends and something else becomes. But in many places part of this will be in basic mechanical engineering or introduction to mechanical engineering part of it will be in course called thermodynamics or applied thermodynamics or energy conversion or something like that. That is one thing I want a brief discussion on. The second thing I want to conclude by the time we come to lunch is the structure of this particular 5 day interaction. As I said that we are not going to this is not going to be a just a lecture course in thermodynamics it is going to be a discussion course. So I would like you to present your ideas to me after the tea break about what is your thinking of the teaching of thermodynamics to undergraduates in mechanical engineering. What is it that you find difficult to make them understand? What are the topics you would like to be discussed right there? Essentially from a teaching of thermodynamics point of view if there are certain ideas which are not clear we will discuss everything from the basic. So if necessary I would not hesitate in you know formally teaching a certain part but that would be in sort of a lecture demonstration mode. Although it is a lecture it will be a demonstration of this is the way we teach it. I am sure there are alternatives I do not claim to have a you know a unique right to teach thermodynamics in a particular way. In fact all this structure has been based on my teachers the others I have seen teaching thermodynamics, good thermodynamics books and recently good videos on thermodynamics teaching which is available on the net. Now just to have the whole thing in line I distribute a quiz this is a two page paper but there are no marks but I have roughly said that spend two minutes one minute or something like that on each and every question there are some ten of them. The last one is matching pairs for which nine minutes are given I think the total comes to 26 or 27 minutes so we should complete this in about 30 minutes and there is no roll number but I do not want you to be fully anonymous in the sense I do not want to know who has written which paper so above the top line make some mark some signature some scribble so that these papers I am going to keep a copy but I would like to return these to you maybe tomorrow or a day after. One of the differences between education implementation in an IIT and other places is that IIT is a large postgraduate program and my postgraduate students are used by me for assisting me as a teacher they are known as TAs and two of my TAs have been assigned the job of helping me out one is Gautam Sahab and another one is Chetan Jain. So let us distribute this and just to tell you that I have come here without any formal material ready with me all I have is this thing on which whatever I write we can see and we have a absolutely blank electronic paper here on which I will write as things go. So first we have a quiz I hope you have enjoyed the quiz I am not going to evaluate this this is the sort of proof of what I expected and but I will generally go through there are some funny things which I have already noticed and we will discuss that I am just going to make a copy of this for my own record and I will return either the original or the copy to you I think I will return the copy to you the originals are supposed to be kept with me. So first thing any comments on this on the questions in the test that was the purpose in fact this test I tried on I have tried a few times and then by the way professor Bhandarkar learnt thermodynamics from me 22 years younger than me right 22 or 23 years younger than me and the way he has learnt thermodynamics from me I think I should start off by saying that I have learnt thermodynamics directly indirectly from a number of people not only from mechanical engineering but also from physics at a very basic level physics textbook level perhaps the first exposure to thermodynamics was by one professor Sundar Rajan then professor Viladkar the late professor Viladkar both from the physics department of IIT Bombay then from mechanical engineering professor Achyuthan later on professor Jagan Mohan Jagdish Sukhathne directly indirectly and then professor Didi Deshpande of chemistry who was my co-supervisor for the PVP program I picked up a lot from him on statistical thermodynamics, kinetic theory and that is the reason why the title says thermodynamics in mechanical engineering and one of the situations we find ourselves is that thermodynamics is although being a basic part of physics and chemistry is a part of a number of engineering branches too. For example a student in mechanical engineering will not be considered fully becked make engineer unless he goes through a study of thermodynamics but so is true of students in chemical engineering, students in aerospace engineering, students in metallurgy material science and if you have some odd branches like automobile engineering thermodynamics is a part of that part too and in any course particularly if you are teaching thermodynamics to youngsters that is first or second year of, second year students in mechanical engineering. The question comes up is what is thermodynamics and what is thermodynamics what is not thermodynamics why are we learning it and what are the predecessors and what are the followers of this. So after having said that just I did some content analysis and I found what I found generally to be true of our first year students in the postgraduate course this is typically administered to newly entrants, new entrants to our MTech program and although it tells me directly about what they know or what they do not know or the way they have understood thermodynamics it also indirectly tells me about the way they have been taught that was an indirect assessment of the way thermodynamics was taught to them this is because you are teachers of thermodynamics this is more or less a direct assessment and what I found is not only for those students who come with a BE or BTEC from outside the IIT system but also for our own students at the undergraduate level and which must be true for your students is that when you start teaching them thermodynamics they already have some idea of some vague idea of thermodynamics from a portion called heat in their high school and some patchwork to study of thermodynamics during that 12 standard that is HSS sometimes in physics sometimes in chemistry sometimes in both and I find that I have to make them realize that although they know how to solve some simple problems in thermodynamics their understanding of the principles of thermodynamics is very very weak in fact the way the our education scheme has been implementing the 11-12 teaching it is essentially you know as professor Fatak said pass the exam get good marks that means solve the problems or answer the questions understanding the basic subject whatever it be is a secondary even today's times of India there are articles about this I think that is because I think from today in many states the second higher secondary exams begin today or this week and I find that many of us also have the same confusion about thermodynamics so before I start telling you something I would like the few of you to say something about what is expected of this interaction and what is the problem if at all you face in teaching thermodynamics or which is not the same thing as teaching thermodynamics making your students learn thermodynamics it is open I would like some hot discussion because as I said that this is not going to be a one-way street of good two three hands there are already sir I would like to say that there are few topics which are very difficult to understand rather it may be from my side or from the student side so I would like to have some discussions on that topic for example entropy available energy and of course the PVT surfaces that is of steam that I would like to discuss that you find is a general difficulty I will give you enough time there is no time restriction and more the discussion better discussion on the thermodynamic relations like a Maxwell equations actually what the when I am teaching the Maxwell equation just I mug up and deliver it actually I would not understand what I have to you know comparing to other units I cannot strong in that particular way okay but I can understand how it is derived and how it is to be you can derive it you know difficulty but understanding understanding is the same thing is for Clausius inequality also okay so things related to second law seem to be one gray area one difficult area okay availability okay we are not able to correlate with the practical example let me let me just note down here we started off by saying generally second law entropy availability how to relate it with the practical example availability then okay Clausius inequality then property relations particularly Maxwell situations not really the derivation but the understanding of the physics behind it PVT surfaces you want to say something actually I would like to learn the basic concepts and their applications how to give the number of application about this thermodynamic topics not related because even though we first law or a Carnot cycle we are explaining it to there is a adiabatic system and everything but students asking the more of questions same thing sir adiabatic process reverse we say reversible isentropic process but how actually the question has been asked in the quiz is that isobaric process is the reversible isentropic or not adiabatic so actually what question on that that adiabatic is a isobaric and it can process be both so what actually happening inside the turbine or the actually adiabatic process not possible in actual case so we are why we are considering theoretical when we are theoretically examining so on that I want to sir evolving Helmholtz and Gibbs function okay that comes to property relations actually I thought thermodynamics only once when I newly joined in this profession so later I thought your background is mech or chemical mechanical mechanical engineering because you know the way they look at thermodynamics is different yes yes I understand later part of my teaching I was only I was given most of the applied part of it like thermal engineering heat transfer refrigeration air conditioning and things like that so when I went to some courses in IIT Chennai and places like that for initial workshops I found that I have totally my way of understanding the things and the way of teaching the things have totally I learned in a different way I have understood the conceptual way a logical way of teaching the things so I came here basically to know to see how a subject which I feel a very fundamental subject for mechanical engineering is taught so that I can dissimulate the same knowledge for the faculty in and around the colleges I came here for that sir I would like to add the same thing that any of topic of your interest let us say just for 10 to 15 minutes you can give us the example how exactly to teach that it may be the simple one or the complicated that will happen that will happen because the way the whole thing is the way it is going I can't do justice to it unless I sort of like them all over the whole of it will be the best example for us also thank you now if I say that except in a passing way I am not going to talk about any molecular disorder and we derive entropy in a very properly engineering way I think you should be happy right now let me ask you any more comments let me make a comment but comments from you on my or even otherwise are welcome because we have another about how much 25 minutes for the tea break as a as I said that just take out the sequence of topics do you generally agree that the sequence of topics is in order more or less so that's one thing now I tell you something in IIT Bombay also for some reason I think historically IIT Bombay have had in mechanical engineering in chemical engineering and in physics also in chemistry very good professors interested in thermodynamics they may not be involved in basic research in thermodynamics because the thermodynamics research ends up being of the applied kind except for development of theories of thermodynamics which all the great minds have more or less done there is nothing much left to do in basic thermodynamics but I think there is a great thing left to do in deciding how to teach basic thermodynamics and I think that's what we are here for and because of that the course in mechanical engineering thermodynamics has evolved over the years as a really good course I have seen the development the way it was taught to me as an undergraduate and the way it changed when I was doing my PhD here in the way it developed as I and my colleagues started teaching I think it has now I shouldn't say fully big but it has become reasonably well big but even then let me tell you something out of the 13 topics listed here 13 major topics listed here the first 11 topics have always been part of our thermodynamics course over the years some have become more the emphasize that changed slightly it also changes the way the teacher is the teacher changes some topics will be deemphasized some more topics will be emphasized it also depends on the speed of the teacher here we have a course syllabus which is in about 100 and 150 words and after that it's like one of those Indian classical music schemes you have a Raga which has a few themes which define the Raga then the singer is left to himself and even the same singer a good singer when he recites that Raga for you know in 10 different performances you will have 10 different implementation but you agree that it's the same Miyake Mallar or whatever it is so that way it changes so I can say that more or less topics 1 to 12 are the proper contents of any undergraduate first course in mechanical in thermodynamics depending on our design of the subsequent courses in the speed of the teacher sometimes introduction to cycles is included sometimes introduction to psychrometry is included sometimes introduction to compressible fluid flow is included because here we have a sequence of courses in mechanical engineering they typically go as thermodynamics fluid mechanics heat transfer and applied thermodynamics or introduction to energy conversion and if a teacher finds that the student crowd is good he can go a bit fast even includes some topic from fluid mechanics like compressible fluid flow which is more or less an extension of our open system formulation that inviscid compressible flow of an ideal gas or even using steam can be taught very properly in a course in thermodynamics that is why that much encroachment is done in fluid mechanics sometimes introduction to combustion also included in the first course in thermodynamics so apart from such divergence I think this 13 topics as we agree is good enough now I want to know there are some 35 teachers here how many colleges or how many syllabi have this in one single course for reasonable number good oh quite a good number and how many places are there where this happens to be partitioned into say two courses like introduction to make engineering some part and some other part not as many as earlier I am happy that thermodynamics it slowly gaining its proper thing now where there is a full course in thermodynamics isn't there a introduction to mechanical engineering course there is no quite a few places there is no introduction to mechanical engineering the few places there will be intro to mechanical engineering but that may not have much of thermodynamics okay that that's good for us because I think and I get a feeling that if there is a majority if you know six years ago so many hands would not have one up because this full course in thermodynamics at that time I know did not exist in many places it was always split into intro to make engineering and something called thermodynamics or applied now what about textbooks which are the common textbooks which are used Nug, Stengel bowls okay, Van Weiland, Sontag, Van Weiland, Borgnath the authors keep on changing in combination okay CPR or IS Balani old one and how much 40th edition that's a huge one but one thing you will agree that which I also find that there is no book which caters exactly to this it's always more than this but I find that in spite of going through those books because those books are written they are excellent books no doubt all of you have said I have not seen Balani I have seen PL there I have seen Sontag I have seen Sontag Van Weiland all those I have seen Nug all editions I have seen Stengel bowls and a few others most of them in one way or the other are very good books for students but they are not really good books for teachers second thing is I think over the years those books have become big verbose and the style has changed in such a way that I think they expect the student to read through the book and understand everything on his or her own I think that is the way perhaps the style has been changing if you look at the books of 1960s and 70s when I was a student it was very clear that the book is written to be used along with some professors teaching in class at that time quite clearly it was written the derivation of this is left as an exercise to the students nowadays you hardly find that in many books in fact I have not seen a book in thermodynamics but I have seen a book in heat transfer big thick one in which one dimensional steady state conduction occupies something like 60 pages in the whole derivation plane parallel slab both temperatures specified plane parallel slab left side temperature specified right side heat transfer coefficient and right side temperature specified left side heat transfer coefficient all these cases are derived so even a Dumbo will get bold if I can say so have you looked at now the books which you mentioned are essentially written for engineers by engineers mainly mechanical have you ever looked at for used books which were written for physicist or biophysicist yes but the Resnick Halliday is at a very very basic level in fact my first exposure to thermodynamics by professor Sundar Rajan where those four or five chapters of thermodynamics in Resnick Halliday yeah why we see now that is but the the tone is entirely different because it is mainly for chemical engineers to some extent it is good perhaps for chemists also and the book by professor Dhar of IIT Delhi see any good textbook not only of thermodynamics but for any other subject should not necessarily or should not restrict itself to what the student is expected to learn through that course the boundaries of the book should be wider than the boundaries of the course material which is expected of the subject is very vast and if you start covering everything of the subject then the library may not be sufficient but there are many books which fall into a trap of the following a good author writes a good book first edition but it's a quick and dirty work the people realize that's good so good feedback comes and the second and third edition perhaps is a very very mature nice thing but then the comments come in my university this topic is included but that's not there in the book then some other person says something else should also be included now this is important that should also be included and then you end up with adding those topics and the book becomes bulkier and bulkier and that you will find not only of engineering books but that you will find of even physics books for example a few of you may know there are very good authors of physics which are friends of engineers for example Zimanski's book on heat and thermodynamics it's a classic and now I don't know whether Professor Zimanski is there or not but it is Zimanski and someone else and the third to fifth editions of Zimanski's heat and thermodynamics are perhaps the excellent ones but from sixth edition so much material started getting included that a good student and even a good professor seems lost in it along with Zimanski there was a co-author Sears, Sears and Zimanski wrote college physics books together so Sears himself has written a book on thermodynamics kinetic theory and statistical mechanics that was my textbook for the physics thermodynamics and I like that book because you know without being partial to microscopic or microscopic theory we gave a more or less balanced thing and not more than maybe 250 pages but of course it was a book for a serious student there were lots of things not loose ends but open canals left for the student to discover I think Sears has retired is no more now Sears and Salinger have come up with new editions of that book and that still remains a good book mainly from the physics point of what I have found is if you go through the second hangout that is exercises the exercises have some 19 pages of exercises in 8 groupings I think the total number is 111 followed by some charts and you have also been given this team table first thing is on the first page behind the title you will find text and differences there are a list of five books and I have specifically not included Nag and it was that St. Gel and Bolt because everybody knows about them instead of just making it longer I have put books which I think you should refer to I think Sontag has already been mentioned but Zimansky I am restricting myself to the fourth edition notice 1957 similarly Sears and Salinger I think I do not think after 75 there is an edition there are only new prints maybe that is why it has remained good but Chudan was one of my professors here I think it is appropriate for me to put him at the top but anyway that is not the reason it is an alphabetical list that is why Chudan happens to be number one Moran and Shapiro is another good book I think the fifth edition has come out after 2000 but I think slowly it is also going the way St. Gel and Bolt has gone initially it was compact and nice and now it has become bulkier and bulkier now it becomes so bulkier that a few years later it will be good exercise just to lift it up and put it down on the table out of which Sears, Salinger and Zimansky are essentially physics oriented so Sontag, Van Weiland, Moran, Shapiro and the Chudan they are essentially engineering with different type of styles and one of my recommendation is once you go back to your institutes colleges see to it that you have at least one copy of these in your library they are good for particularly for a teacher to refer to. Now the charts I have obtained from the internet there is nothing special about them and also there is nothing special about these steam tables I have given you a copy just to see to it that when we come to the discussion of steam tables we are on a common ground otherwise what happens the style perhaps the units the number of significant figures the way things are tabulated the spacing are all different in different tables although the principle remains the same it is good to have a common basis so listing this here does not mean that this is a strongly recommended steam table but it is a good steam table and we have been using it for how much 20 years or something like that the only a few weeks ago the 10th edition or no I do not know the edition number 2010 edition has come up and we have found that that is good enough for our purpose. So now after the almost tea time may be oh inadvertently I have started with 1.1 x books and other materials so is it okay to start our discussion more or less in this order I want continuous feedback as to please emphasize this please illustrate this in more detail or why not a divergent and things like that so we will because we have agreed to this we will generally go in this scheme and this is more or less the scheme of thing which is followed by us in our thermodynamics teaching so I have kept it but the context here will be different we have already discussed textbooks the next topic here is evaluation scheme usually this is the time when I tell the students that we are going to have so many quizzes of this type and what is the penalty if you misbehave during the quizzes etc. But see in IITs in particularly in IIT Bombay we have a I should not say reasonable we have very very flexible when it comes to evaluation scheme you can get away with the almost murder so long as you have something called an in semester exam with some weightage to it and which is you know held according to the centralized timetable what you do during the semester is essentially left to the instructor or the teacher I am sure a few only a few of you will have this flexibility what is the type of evaluation scheme that you have I think all of us now are in the semester system I think nobody is remaining in the annual system anymore and that means you have some in semester evaluation and some in semester evaluation how much is the weightage for the in semester evaluation 50, 60, 80 any place where it is 100 so out of 150 marks 100 marks are absolutely that one single exam so I can say about 67% roughly some people said 50% where is that but which this is PHG tech that is okay I am mainly interested in the end semester examination 50% 50% okay you also have online university 75 but no generally what I see is 50 to 80 seems to be the range okay one way or the other but there is no 100% weightage for is there any means some some weightage is there for what you do during the semester okay now and I think that is true for each and every subject that they learn throughout their this thing whether it is mechanical engineering whether it is economics whether it is unless something which is purely laboratory work which will be different so fluid mechanics will be treated in a similar way strength of materials will also be treated in a similar way I am not paper can be one million mark does not matter okay that that is a matter of local detail okay so in the university itself it is 50, 50 but affiliated colleges it is 20, 80 type okay that means within the university there is a difference direct colleges and affiliated colleges. So you have 50, 50 yeah so but the papers also will be different syllabus may also be slightly different okay now what I feel is that and I have done experiments over this and I have more or less come to a conclusion that at least for the type of students we get here the standard IIT scheme I modify the standard IIT scheme today for any course if you do not say anything this is what everybody will be doing typically 3 hour paper 50% that is after 14 weeks of teaching after 7 weeks of teaching we have currently it is going on this week that is why I have scheduled it this week from my convenience we have the mid-semester examination a 2 hour paper 30% right now that means 20% weightage remains that 20% weightage is distributed by the teacher any way he or she feels like any combination of quizzes assignments by was some minor weightage for attendance could also be there some small maybe 5% 10% no more than that usually by default many teachers tend to do after about 4 weeks of teaching a test of 1 hour 10% weightage then after 7 weeks of teaching mid-semester 30% another 3, 4 weeks of teaching a test of about 1 hour 10% and then finally 50% ends in my experience shows that in thermodynamics there are so many small, small items which one has to learn and unless that learning is complete or unless those concepts are absorbed or unless I force the student to absorb those they are learning and absorption of the following concept becomes difficult and hence left to me I would conduct a quiz and the quiz is essentially of the type which I gave you the format is not the content typically one sheet single sheet write your the space for roll number and name the question here and everything else is blank yes but now the difference I will tell you typically 15 or 20 minutes once every 2 weeks no mid-semester so I end up with about 6 or 7 quizzes in a semester and I give a weightage of 60% the end semester is a 3 hour examination 3 hours because they sit parallel with other students I do not mind having it even a 2 hour examination but then the others will get distracted here that the end of 2 hours all thermo students will be very happy that their exam is over and they will make lots of noise and students and teachers of other courses will be complaining so a 3 hour paper no more than 40% and I have found that not only is it good for the teacher because the students are alert they know that a few hours later there is going to be an examination the exercises what I have given you is a almost complete set may be some 10 or 12 exercises which are more or less repeat or essentially for the student warm up that I have not included but those 111 problems I suppose they are so is essentially the heart of our undergraduate thermodynamics due to real sheet they may be rearranged in different form the way the teacher. So you can say that about one tutorial sheet out there comes to more or less one quiz sometimes more sometimes less but roughly of that all and because of that a student is forced to learn something almost every week I understand that in a university system and in an affiliated system this is not possible but it is possible that a few of you will be in colleges which are autonomous or few of you will be in colleges which are thinking of becoming autonomous or you will end up in one such college and autonomy does not necessarily does not only mean that you are free of the day to day interference and day to day governing by the university you are free to take your own decisions and that not only means the top management of the college but also the heads of departments and also the faculty becoming autonomous more or less for their course and when that comes I do not want a discussion now start thinking for whatever course you are teaching what is the best way to evaluate students because remember our way is our job is to teach but the end product is that the student should learn and we should do everything which would make the student learn in a friendly and comfortable way and I find that a quiz every alternate week during the class over a tutorial hour 15 20 minutes and a short problem no extra paper this is the question this is the space that you that works best okay just and this is what I wanted to tell you about the evaluation scheme I agree that immediately it not be possible for you many of you but if at all it is possible think over I have told you what my scheme is but based on your experience you come up with your own scheme. Now the next one mechanical engineering thermal engineering and thermodynamics one of the problems that we all face is that students come to engineering and students in IIT are no exception many of them come to engineering and take up a particular branch of engineering because of what we call the mob mentality you are a good student you should take up science in 11 and 12 oh you have done well in science you must appear for your CET or JEE or whatever those dozen examinations are conducted oh you got a good rank in CET you must take computer science and oh you have you must go to this college oh you did not get computer science what is the next best that depends on you may be mechanical may be electronics may be what have you the liking of the student and the inherent goodness of the student in engineering in general and mechanical engineering in particular is not really looked at consequently a teacher has to make some effort in keeping the students interest live in engineering in general and mechanical engineering in particular and because a decision has been taken by many students almost by default that they will sign up for a BE or BTEC in mechanical engineering you ask them what mechanical engineering is about we do not know it is something to do with cars something to do with something I tell you a personal story when I signed up for engineering my old grandmother father's mother called me up and say hey I heard you are going to become an engineer said yes then she asked me what type of engineer this all happened in local vernacular Marathi Konkeny combination I tell you it in English then immediately my problem was how do I explain to her what mechanical engineering is but perhaps she noted my hesitation and she said I know three types of engineers tell me which one you are going to be here one engine one is the one engineer who builds houses and such stuff another is an engineer who you know lays out all these wires for lights fans and such things third is an engineer who looks after cars locomotives and such machines no I was surprised at that time that that old lady may not have learned more than a few standards I do not think she ever went anywhere near SSC but she had a perfect grasp of grasp of what the three basic then branches of engineering so I explain to her that well I am going to look after the engineering which takes care of cars steam engines trains and all that and I was in mechanical engineering what I did not realize that as I grew in mechanical engineering my interest in thermal engineering and in thermodynamics would grow but you know even you ask a student what mechanical engineering is about what is engineering about what do we do it for they are not sure what they are and hence it becomes very difficult for them to understand what is the place of thermodynamics in mechanical engineering and why should we learn thermodynamics and this this confusion exists because they have been exposed to something called heat or thermodynamics in school typically in physics courses they have done some simple calorimetric experiment they know that you know heat lost by the calorimeter is gained by water and you have water and then there is a blob of copper in it a hot blob or a hot water in which you put the cold copper and measure the change in temperature all of us have done this experiment in school then we have something called a water equivalent for the calorimeter so all these confusing terms are there then they come to 1112 standard I think in 1112 in many places physics doesn't have much of thermodynamics but chemistry has enough thermodynamics so they end up with a gas means PV must be RT they end up with an adiabatic process means PV raise to gamma is constant you ask a student what is heat oh heat is MC data T because that is the formula which is needed for you know getting those two marks or two and a half marks in CET and with such you know vague ideas may not be totally incorrect but incompletely assimilated ideas they come to us and then they suddenly are confronted by the fact that oh I mean mechanical engineering there is a big subject called thermodynamics hundred mark paper and what's so great about thermodynamics in it why am I learning it and then you find that is colleague in chemical engineering also doing thermodynamics but his textbook is different the way his teacher talks about is different the way his sketches diagrams is different he is using some triangular graph paper which we have never seen then there is a student in metallurgy material science whose thermodynamics is neither like mechanical engineering neither like chemical engineering some things are common but they are entirely different in metallurgy material science they never talk about something which is flowing they don't worry about open thermodynamic systems and in chemical engineering they always talk of either a closed reactor a continuously stirred flank reactor an open process they talk of batch process and continuous process so this leads to confusion