Tata Elxsi Placement Papers

TATA ELXSI PAPERS HELD AT DRIEMS ,CUTTACK ON 24th APRIL 2004 

         There were two rounds 1)TECH(30 ques,30 mins)2)APTITUDE(30 ques,30 mins)

         TECH QUESTIONS (Electronics & TC)

1.                  CMRR is given=
Differential gain is given=  
Inputs:
+ve end=2v,-ve end=1v of the OP-AMP                                                            
Find the output voltage?

2.                  CRO is in X-Y mode.Sinusoidal inputs have 90degrees phase difference between them. What will appear on the display? a)circle b)line c)ellipse d)triangular wave

3.                  Which has least propagation delay?
   a)ECL b)TTL c)RTL d)CMOS

4.                  In a ripple counter how many change in states happen when count changes from7 to 8?
a)1 b)2 c)3 d)4

5.                  Max. no. of variables that can be represented in K-MAP?
    a)3 b)5 c)7 d)none of these 

6.                  How many comparators are required in a n-bit flash ADC?
   a)2^(n-1) b)(2^n)-1 c)2^n d) n

7.                  What is an EEPROM?
   a)Programmable transistor
   b)Transistor
   c)SRAM
   d)

8. Time period of input voltage=8ns. / Find the duty cycle of Vout.                                          
     
   Voltage across one capacitor is V volts. Another cacitor is added at its one end(now the two are in series). What is the voltage across their ends?
    a)V b)V/2 c)2v d)none of these

9.                   In an SCR why silicon is used?
     a)  available easily
     b)  has much less reverse saturation current than Germanium
     c)  has greater reverse sat.current than Ge
     d)

10. Output=?
       
    
         a)A’+B’+C
         b)A+B+C’
        c)A(B’+C’)
        d)B’+C’+A’
11. There was a question using transmission gates.Three inputs were A,B,C.Answer was  (A+BxorC)
12. How to get the characteristic figure changed from 1 to 3?(characteristic diagram)
      

            a)By increasing gate width of NMOS
            b)---------do----------------- of CMOS
            c)By increasing gate voltage

14.  Find propagation delay?
                                        
        a)200Hz b)150Hz c)5Hz d)2Hz

15.              A diagram was given to identify?
   a)Synchronous counter
   b)Ripple counter
   c)Shift register
   d)None of the above
     answer was sync. Counter

16. Find Va?and Ia, Ib?
       
17. Find ammeter current Ia?
                                         
           a)10V  b)9.09V c)11.01V  d)0.9V    these options may be wrong.
18.            
       This acts as a:
       a)OR
       b)XOR
       c)AND
       d)NOR
19. At t=0 if position is changed from 1 to 2 ,find the voltage across 1KΩ?
        
       a)4V b)2V c)1.5V d)none of these
20. Find thevenin voltage and resistance across A and B
      
21. how will be the output voltage across R ?
     
           
    
                    
        Ans C
22. What is this ?
       
    
    a)Integrator b)Differentiator c)Antilog differentiator d)Log differentiator
23.  
    
      Flip-flop state diagram question.What does the above represent?                                     
24. What is this?
      
    
       a)Squaring device b)Divider c)Square root ckt d)
25. How will be the output vs. input graph if Vin=10V,sat voltage of OP-amp is 14V?
     
    
    

26.              Basic memory cell of dynamic RAM a. Capacitance
b. Flip flop
c. Transistor
d. Transistor with Capacitor

27.               Ideal Power Supply has
a. Zero internal resistance
b. High O/P resistance
c. High I/P resistance                                                               
d. Low O/P resistance

28.              Which type of transmission line will have max. value of characteristic impedence a. Open Wire line b. Coaxial Cable
c. Twin lead line    d. None

29.  For same peak value of current, which waveform will have least RMS value a. Sine b. Square
    c. Triangular
    d. Full wave rectified wave

30.              -V analogy displacement is analogous to
a. Voltage b. Condutance
c. Magnetic Flux Linkage
d. Capacitance
Similarly..............In F-I analogy displacement is analogous to
a. Charge
b. Resistance
c. Inductance
d. Current

31. In the following circuit Vo/Vin = (there were 4 options)
        
32. In the following circuit the charging and discharging time is  (i don’t remember the options)
       
       Don't remember the other value of other res and cap .But some values are given                
33. The output at X acts as….
      
               a.OR gate
              b.AND gate
              c.XOR gate
            d.XNOR gate

34.              The CRO in X-Y mode gives the following figure. If signal applied to the Y-plate is 2sin(wt) then the signal  applied to the X  is    a. 2 sin (wt) b. 2 sin (wt + p/4) c. 2 sin (wt d.2Ö2 sin (wt + p/4)
   

1.                  How many triangles are formed in a octagon.   Ans: 56( check the answer)

2.                  A hexagon is fitted in to a circle of radius r. perimeter of the hexagon is ?    ans: 6r

3.      Max. difference between two birthdays of a man. a.  365days,     b. 366days       c. 4  years      d. 8years

4.                  Which is greatest no. between 2³⁰⁰ and  3²⁰⁰?  Ans: 3²⁰⁰                                                                   

5.                  Which is the greatest no divisible by 101¹⁰⁰  -1?

6.                  In a school no of boys is twice that of the no of girls. Half of the girls are in hostel. If the no of girls in hostel are 5 then what is the total no of students in the school.             Ans:30.

7.                  In how many ways 7 girls and 4 boys can be seated in a circle such that all boys sit together?        Ans: 4! 7!

8.                  Complete the series  3  7  11  _  19   23           ans: 15

9.                  A square is inserted in a circle and an another circle is inserted in that square. Then the area of the smaller circle will be ______________ ans: 50% of the bigger circle

10.              Boat problem: speed of the boat in still water is given. And speed of the steam is given. Asked for some time. Easy problem.

11.              In a match SA scored at a rate of 4.6 runs per over at the time they were all out. India chased it in less than 4 overs of total match. (ie. on46 overs). If the runrate was 15% greater than the original rate then match may be completed 6 overs before. Then what is the total runs scored in the matc .Ans: may be none of the above

12.    The sum of the ages of father and sun is 45. 5 years b4 the product of their ages is          4 times the age of the 

          father. Then what is the age of father?     Ans: 36                                                

13.     A problem on tank leackage                                                                                                 

14.     In a match total runs scored by sachin, sourav and dravid are 342. the ratio of runs scored by sachin and 

          sourav  is 3:2 and sourav to dravid is 3:2. then what is the no of runs scored by sachin? 

          Ans: 162.  Sourav—108       dravid – 72

15.     A man if goes to his office at a speed of ¾ th of his normal speed, then he reaches office 50 min late. Then 

          what is his normal time to reach office?

16.     The time in clock is 2 past 20 mins. Then what is the angle between min and hrs hand?    Ans: 50 degrees

17.    In an A.P. series 5 times of the 5^th term and 8 times of the 8^th term are equal then what is the 13^th term of 

         that  series?   Ans: 0

18.   A passenger train with speed 60kmph and a goods train with speed 20kmph are moving from a station X to

         Y. the passenger train reaches 50 mins before the goods train then what is the distance between X and Y?  

          ans: 25km

19.   One travels at a speed of 40kmph for some distance and 60 kmph for some distance total distance of 240km

         is traveled in 5 hrs. for how much time he traveled with 40 kmph.( not sure abt the question it is in the same 

        fashion)

20.  The time taken to move around a circle of radius 21 is 44 min. then what is the time required to move around

       the hexagon of radius 42?    Ans: 84                                                              

21.  x² + 4y² =  4xy. Then the ratio of x and y is ___________   ans: 2:1.

Two seperate tests:

1.   Technical (30 questions-30 minutes) - Separate questions for CS and EC. Technical was conducted first, 

      followed by Analytical.No Negative marking.No Separate Question Booklets.Everybody had the same one 

      -Technical test (for computer science) consisted MAINLY 'C' questions. And most of them were difficult ones. 

      There were 3 questions from Computer Graphics (Tata Elxsi is also into Multimedia Development, that may be 

      the reason)                                                                                                              

2.   Analytical (30 questions-20 minutes) Analytical test DID NOT HAVE ANY ENGLISH QUESTIONS.
      R.S Aggarwal's 'Quantitative Aptitude' would be very helpful here because there were questions asked from 

      numbers/Simplification/Problems on Ages/Profit and Loss/Ratio and Proportion/Time & Work/Pipes & 

      Cisterns/Time & Distance/Problems on Trains/Problems on Boats & Streams /Area/Volume & Surface 

      Area/Calendar/Clocks. So as you can see, they covered almost the entire book

                                   Technical Test Paper

1.    Graphics:Painters algorithm is used for...........

2.    Graphics:Why is 'Lighting' operations done on World Coordinates?

3     Graphics:One more question Ans: may be none of the above

5     How can you call a function written in FORTRAN from a C program ?

6.    Normal question on pointer addition

7.    Another question on pointer adition

8.    A question on 64 bit OS's and Virtual Memory it will be having                               

9.    Another question on 64 bit OS

10.    A structure was given and it contained normal data as well as some bit-wise data.You had to find the total size 

         taken up by the structure

11     A big code with lots of pointers. There was a struct which contained 2 arrays. Then an array of that structure 

         was declared. The code used these structures and you had to find the values of a variable 'j' at various points 

         inside the code.

12     A code which had some declarations of some data items. There were a couple of normal data items(char,int..) 

         and some pointers as well and a malloc call. You have to find the total memory taken up in the 

         stack(Hint:Pointers 

         and all are allocated in heap, not in stack, so dont count them).Also in most of these questions, they were 

         specifying that  the OS was 32 bit.

13.    A question on nesting of pointers. There was this pointer to a function which returned an array of char 

         pointers.....You had to give the exact definition of the function

14.    Value of 2 particular variables in C(MAXINT and some other constant)

15.    What do you need to do to open more than 10 files simultaneously in Microsoft Operating System?

         -change stdio.h/change CONFIG.SYS/compiler dependent

16.    A question on Macro( consisted of something like CTRL&037)

17.    Another question on Macro expansion

18.    Yet another question on Macro expansion

19.    UNIX question on 'who' output and then doing some other operation and then asking you whats the output.

20.    UNIX question on 'awd' operation

                  Analytical Test Paper

1     101^100 -1 is divisible by.....

2      Question on boat ( stream velocity given...)

3      Train Question( Goods and Passenger train.. their speeds given..)

4.     Pipe question (with leak at the bottom..)                                                            

5.     Salary & Proportion problem

6.     Another problem on Salary & Proportion

7.     Age question-father and son                                                                          

8.     Another age question

9.     Questiononratios(Sachin:Saurav=Saurav:Rahul=3:2....together they scored some runs,you had to find the runs 

         scored by Sachin)

10.      Angle between hands when time is 2:20

11.      x^2 + 4 y^2 =4xy.Find x:y

12       A question on Arithmetic Progression(something like 5 times the 5th term is 8 times the 8th term..find 12th 

           term...)

13       A and B's work units given.They were together gievn Rs.720.When C joined,they together completed the       

           work in 5 days.Find C's wages

14.      There was a circle.A square of max size was cut from it.From this square,a circle of max size was cut.What 

           was the ratio of this final size w.r.t initial size?

15.      A runs 3/4th faster than B.One of them was placed some metres ahead.How far should the finishing post be 

           placed so that both of them finish at the same time?

16.      Longest time one has to wait for next birthday?(366/365/4 years/8years)

17.      Next no: in the seq: 7,11,__,19,23                                                                    

18.      Some question on steps...it was 10 ft high...an ant travelled upwards..and total time taken

19       Cricket-some data on runrate of the opposition being 15%....

20      Time & Distance..somebody was travelling along the circumference

Tata Elxsi Questions 

1. Problem on lissojous pattern: in x-y mode if vlg applied to x-axis is 2 sinwt then what is the vtg to be applied to y-axis so that we observe the following pattern on the cro : [angle b/n x-axis and the diagonal line is 45degrees] ans is 2root 2 sin (wt +45)
      
2. What is the resolution of an adc : vref/(2 pow n).
3. Some circuit is given with two f/f s ,what is that circuit? Ans may be shift reg
4. Spatial to temporal converter is ? (a) shift reg ( b) counter (c ) adc ans may be adc 
5. Darlington is used for _____ ans high current gain
6. Some circuit with nand gates is given ,what is that circuit ans is xor                                    
7. A wired circuit with some nand gates is given asked the function of that circuit
8. An opamp circuit is given asked to find the transfer function of it ( I think its an ideal integrator circuit)
9. A pole zero pattern of an impedance function is given . it has a conjugate pair of zeros and a conjugate pair of poles ,then what elements does the impedance consists of? Ans LC elements
10. Most computers wont use floating point arithmetic .why        a.costly b. slow c. cant
11. Bit-slice processor mean …… ans used for shift ,masking of bits 
12. ac motor used in servo applications is (a) single phase induction b.2 phase induction c. 3 phase induction
13. TV resolution depends on a. bandwidth 2. detector c. no. of frames /sec
14. Equalizing pulses are sent in tv during a. horizontal blanking b. vertical blanking ……….
15. cdma is not suitable for satellite communication . why ? ans may be complexity of operation 
16. Given some waveforms and asked that which of the waveforms will have odd harmonics of sine terms
17. Asked for two’s complement of a number
18. maximum signed no. represented by a 8 bit computer
19. A chip has a capacity of 256bits,to implement a 1KB capacity how many chips are required ans 32
20. ecl operates in ____ and ____ regions of the transistor 
21. Given a transient circuit ,asked for time constant while charging and discharging 
22. He had given 4 statements about a f/f and asked which of them are correct 
    1. it can store a bit 2. jk f/f have rat race when storing a 2 bit info 3. master slave is used to store a 2 bit info 
    4. d f/f used as a latch for multiplexing operations 
23.  Venn diagram is given and asked to write expression for the shared portion in it                          
24. cb and ce are ____ biased when transistor is in saturation 
25.  condition for nyquist rate
26. carry look ahed adder is 1.fast 2. requires more h/w 3. costly
27.  ideal power supply will have a. zero internal resistance b. more o/p resistance c. less o/p resistance 
28. A problem on cro and probe interface i.e design of an attenuator for the cro probe (formula for it is R1 * c1 = R2 * C2 )

The test consisted of 2 sections one technical section 30 questions. to be answered in 30 minutes it included questions mostly on C and some 5-6 questions. on OS The C portion was difficult and the average score was around 15-20 The questions were totally different...not from Test your C skills... there were quite a few mistakes in printing so assume them accordingly some people told that quite a few questions. matched with a book C under DOS test so if can get that book it's well and good else be confident with what u know

1.      nt a=9;
   switch(i)
   {
     printf("hello");
     case 9 : printf("abc");
                       break;
     default : printf("def");                                                                              
      }
     what would be the output ?
   ans : the program will compile correctly with no errors but will give undesirable results

2.       int z[3]={1,2,3};
    int *p=&z[1];
    int x=*p++;
    printf("%d",x);
   ans. note here that the value of *p will be assigned to x and then p is incremented therefore x=2

3.      #define paste(a,b) a##b
   main()
   {
     int a=3,b=6;
     paste(a,b);
     return o;
   }
   question. what code will be replaced at the call of the macro 
   options : (a,b) a,b (a,b)
   (ab) a,b (ab)
   (a,b) ab (a,b)
   ans. not able to work it out

4.      some structure declaration was given
 struct abc
  {
    int a : 4
    char c : 2
    int abc;
   }
ques. what will be memory allocated to it when we define an object of this structure

ans . the bits are added and rounded of 2 next higher byte                                             
eg. 5 bits - 1 byte
1 bit - 1 byte
9 bits - 2byte

5.      some ques. on memory allocation so clear ur funda of memory allocation properly

6.      To declare a boolean variale in C what method we follow ans. using bit feilds

7.      What does painter's algo. is for in graphics  ans. don't know 

8.      Some complex ques. on bitwise opeartors 

9.      Which is more efficient calling a function by its name or by using a pointer to the function

10.  External functions and external variables are all global 

11.  There are 5 jobs A B C D and E u have to schedule these jobs using the SPT , DD and STR ( i cant 
remember 
the fullforms) and job processing time was given constraints:
Spt = DD
STR = DD - SPT
ANS: using this table u can solve the eqs
spt E C A B D
DD E A C B D
STR E A/B D C
order of excution

12.  c = prt/ropd prt = production/rate ropd = rotations Nt = T/c E = T/Na * c Na = whole number  
according this formula there WERE 5 qs

13.  A B C D E are 5 boys and find the ages of them given 1) B-A = 5 
2) B>A 
3) D>F 
4) E-D<2
5) D-F > 2
6) All of the above are false

14.  About dress and ,Who will be wear which derss                                                    

15.  About the graphics similar to java function draearc drawrect, find the area, center by giving values to function    
drawarc.
1. about process ( os )
2. stacks (data struct..)
3. graphs ( binary trees)
4. time complexity of the c program they had given
5. c program ( recurrsion find the no. of print stat exec. in the recu. func. ans. 4) 

16.  About the soft. engineering i.e identify the phases
1) collecting the information - requirement analysis phase testing or design .. ( similarly identify the 5 statemnets
they had given) 

17.  Choose the correct expression                                                             
((())) correct 
()(()( incorrect.

18.  Graphics question (4 q's)
no q's on unix commands, macros