Semiconductor Electronics: Materials,Devices and Simple Circuits

Hita is preparing for this topic in her IIT-JEE Coaching center.

  1. This topic is in the mains syllabi only. Not there for JEE Advanced.
  2. So there is a tendency to go light on part of students and institutes.
  3. However myself having studied BTech (ECE) helps and Hita is forcing me to recollect all basics.
  4. since simple ckts are tested here we have followed NCERT, HC Verma, GC Agrawal.
  5. HC Verma has interesting problem no.28 on diode ckts. good combo of ckt theory and diode biasing.
  6. GC Agrawal has good collection of questions MCQs and Integer type.
  7. However this carries weightage in NSEP & Olympiads.
  8. I have collected simple problems from GATE material, Prev Question Papers which are highly relevant.
  9. Particularly Zener Diode operation as a voltage regulator is interesting and Hita had adequate practice I hope.
  10. Logic gates though simple has a chance committing silly mistakes.
  11. Two terminal diode operation is straight forward though understanding 3-terminal transistor requires a bit of effort.
  12. n-p-n Si transistor in CE configuration is only required in the syllabus.

Question Paper NSEP 2014-15

NSEP 2014-15 surprised many students including Gangineni Hita.

  1. IAPT removed the Part 2 subjective questions.
  2. Increased the no of objective questions to Seventy from around 35.
  3. Involves lot of calculations rather than generalized form.
  4. Touched many experimental aspects like IPhO Model.
  5. I surmise the popularity of NSEP is increasing and places lot of challenge on question paper setters.
  6. 7 questions on potentiometer surprised me as students from AP may not have emphasised these topics.

Best Wishes to all NSEP Test takers

I convey my best wishes to all Physics enthusiasts there taking the NSEP test today during 9.30-11.30 am.

  1. This is the first step to IPho.
  2. If nothing else this will greatly help them in consolidating their physics skills.
  3. From tomorrow I would start focussing on INPhO- 2015.
  4. Lot of resources useful for problem solving are found  here
  5. IPhO 2015 to be held in Mumbai, may be if the stars align I will be present there along with Dora.


Referred Books for NSEP 2014-15

Ì would like to list out the reference books Gangineni Hita followed for NSEP Prep.

  1. NCERT Vol 1& 2
  2. NSEP Prev.QP – IAPT Publications
  3. Physics Olympiad problems – MTG Publications
  4. 36 years prev.iit qp- DC Pandey
  5. Problems in Physics – Abhay Kumar Singh
  6. IE Irodov- Solutions – 4th edition by AK Singh- Wiley Maestro Publications
  7. Telugu Academy – Question Bank- Vol 1&2
  8. Concepts of Physics – HC Verma- Vol 1& 2
  9. Advanced JEE Physics – Different Volumes-  Rahul Sardana

1-Day to go for NSEP 2014-15

Only a day left for the much awaited NSEP for Hita.

  1. Today we have tried to review all the questions we had with Dora for 2 hrs.
  2. Hita is in 10+1 where as the syllabi covers total Inter. We have prepared our level best in 10+2 topics like Electricity & Magnetism, Optics, Modern Physics.
  3. Right now we are reviewing some topics like Units & Dimensions, Physical World, Errors, Semiconductors which are on the periphery.
  4. Enrollments in NSEP for this year may have crossed 50K , I suppose.
  5. Dora motivated Hita about quickness,accuracy and need for neatness in Diagrams etc. Hita is all ears.

progress in NSEP prep

Hita is continuing her quest for NSEP 2014. We have done question papers of NSEP 2000-2014, IITJEE 1997-2014.

  1. Hita identified some problems where she would like a clarification/opinion from DORA.
  2. We are also marking questions from 35 years prev qps  in Physics by DC Pandey. Probably we will go to Dora on Friday.
  3. Solving questions from prev.papers of NSEP,IITJEE would help Hita calibrate her skills and hone her conceptual understanding.
  4. I would like her ideally to start IRODOV and A K Singh after her NSEP exam.
  5. Maybe conceptual questions from HCVerma, Resnick & Halliday , NCERT books also need a thorough review by Hita.

Previous IIT JEE Question Papers

G.Hita started practicing prev.qp of iit-jee .I felt she has a reasonable idea of the fundamentals needed to practice questions. Anyhow due to paucity of time we started question papers .

  1. I could get hold of only upto 1996 exams only.
  2. The quality of question papers increases as u move from 2014-1996 as Hita observed.
  3. I needed qps upto 1988 as DORA would have appreciated these qps of subjective nature.
  4. May be i will review some topics like Error analysis, Units & Dimensions and Modern Physics.

Semi-Conductor Devices – Hita’s NSEP Prep

Today after her exam,we went to my classmate at SVUCE and an Electronics Engineer KVN Pratap Reddy’s house @ Tarnaka. We had a fruitful discussion for 3 hrs regarding Diodes, Transistors and some problems.

I hope Hita has gained some confidence in Semiconductor Devices topic for NSEP exam.They have tried some prev Gate questions on Electronic Devices also.

I think we need a topic expert model (TEM) where people from physics are not familiar with these topics including Communication systems.

Experimental Skills – Need for NSEP

Hita wants to get a handle on Physics experiments and familiarize with the instruments used in measurements. IIT JEE Mains 2015 gives us a glimpse of expts  the students need to be familiar.

Familiarity with the basic approach and observations of the experiments and activities:
1. Vernier callipers-its use to measure internal and external diameter and depth of a vessel.
2. Screw gauge-its use to determine thickness/diameter of thin sheet/wire.
3. Simple Pendulum-dissipation of energy by plotting a graph between square of amplitude and time.
4. Metre Scale – mass of a given object by principle of moments.
5. Young’s modulus of elasticity of the material of a metallic wire.
6. Surface tension of water by capillary rise and effect of detergents.
7. Co-efficient of Viscosity of a given viscous liquid by measuring terminal velocity of a given spherical
8. Plotting a cooling curve for the relationship between the temperature of a hot body and time.
9. Speed of sound in air at room temperature using a resonance tube.
10. Specific heat capacity of a given (i) solid and (ii) liquid by method of mixtures.
11. Resistivity of the material of a given wire using metre bridge.
12. Resistance of a given wire using Ohm’s law.
13. Potentiometer –
(i) Comparison of emf of two primary cells.
(ii) Determination of internal resistance of a cell.
14. Resistance and figure of merit of a galvanometer by half deflection method.
15. Focal length of:
(i) Convex mirror
(ii) Concave mirror, and
(iii) Convex lens using parallax method.
16. Plot of angle of deviation vs angle of incidence for a triangular prism.
17. Refractive index of a glass slab using a travelling microscope.
18. Characteristic curves of a p-n junction diode in forward and reverse bias.
19. Characteristic curves of a Zener diode and finding reverse break down voltage.
20. Characteristic curves of a transistor and finding current gain and voltage gain.
21. Identification of Diode, LED, Transistor, IC, Resistor, Capacitor from mixed collection of such items.
22. Using multimeter to:

(i) Identify base of a transistor
(ii) Distinguish between npn and pnp type transistor
(iii) See the unidirectional flow of current in case of a diode and an LED.
(iv) Check the correctness or otherwise of a given electronic component (diode, transistor or IC).

I would try to get some acquaintance for Hita in 2 days for expts.