The main motive of iit jee exam is to select not to reject so problems are always a mix of simple and difficult once. With the time it become simpler because more students are appearing in iit jee than before and seats are also increased with time.
Most student think that iit jee is very tough exam having difficult problems which is a wrong concept. If all problems are tough then score will be very small and how it will differentiate between good and poor students. And if all problem are simple then scores will be very high same
situation will be there.
The level of problems asked in iit jee is changing with time year by year. In 1990s 100 mark iit jee paper contained 10 problems 10 marks each,
and a problem may be of full 10 marks or 2-3 part of a problem adding upto 10 marks.
It were numerical based and derivative type all mixed and objective problems was limited to iit jee screening exam only. Only screening exam qualifiers can appear in iit jee final exam.
Problem in final exam which was written type was very good and lengthy and one can say it were very tough. While with the time problems become little smaller hence less time consuming and less tough going but beauty of concepts was very well maintained.
In 2000s iit jee problems become more objective and other type and fully OMR based problems and answers sheets were started. It were simpler but still great.
Although problem from 1990s to 2010s become much simple and it is easy to score more and students now can solve more problems in iit jee paper.
Selection percentage in 1990s was 25% and now a days it is 35% or more. So level of problem is mixed and one should prepare accordingly.
In past papers variation in level of problems had noticed. Although It is not an alarming sitution but still a matter of consideration.
We have to analyse it properly, as in jee advanced 2015 chemistry paper was very tough, Only a few could solve more than 15 problems out of 20. Solving more and more problems is not an correct approach, but to solve as much problems as accuratly is best way. Most students reads 100% understands 90% syllabus. Feels comfortable in 80% does good in actually 70% in exam hall. Gets 20% error or silly mistakes and negative marking effectively reduce it to 40-50%. In a tough paper it is 30-40% only. And final result may be even lower. To avoid such situation students must follow rule of accuracy, rather than maximum problem solving approach. If one student solves 60% problem of physics, maths and chemistry correctly then will be at best rank in iit jee 2017.
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