BEL has conducted the Probationary Engineer Exam in 2008. BEL PE CSE Previous Papers 2008 contains 150 questions. 150 questions were asked from technical as well as Aptitude and Reasoning Chapters. Here we have provide some Technical questions which was asked in 2008 Examination with their answers. Computer Science Students should prepare these questions for the upcoming BEL PE CSE Exam.

**BEL PE CSE Previous Papers 2008**

1. Given probability for A to fail 0.5 and for B to fail 0.3 then what is the probability of either A or B fail?

2. Rita told mani that,”I saw a girl yesterday who is the youngest daughter of brother in law of my friend’s mother” what is the relation between her friend and the girl she saw ?

**Answer : Cousin (chk)**

3. 750 hrs of quality test was conducted on 10 components, at the end of 350 hr, a component failed. What is the probability of failure per hour?

4. Given the P(A) and P(B) and probability of occurrence of both… try to know the logic to find probability of neither A nor B.

__Technical Questions :__

1. No. of cross points needed in a single stage switch having 40 inputs and 50 outputs

**Answer : ****2000**

2. No. of crosspoints needed for 10 lines in a cross-point switch which is full duplex in nature and there is no self- connections is

**Answer : ****100**

3. when |z-5i| / |z+5i| = 1,where z=x+iy a) lies on x-axis b) straight line c) circle passing through origin d) none

4. Gateway is applicable upto which layer ans

**Answer : **Application layer

5. Questions to find the avg access time of CPU when hit ratio is 0.8 and time to

access primary memory is 10ns and that of secondary memory 50ns? (hints: h=0.8, c=10, M=50, avg acess time = hc +(1-h)M)

6. How many 256 * 1 RAM chips were needed for 1 K bytes of memory?

7. Disk scheduling problems (dont remember it exactly)

8. Two represenations of zero in a) prefered ans:sign magnitude b) 1’s complement c) 2’s complement d) none as both sign magnitude and 1’s complement hve 2 zero representations (chk)

9. Few questions from Theory of computation.

10. Problems from linear and quadratic hashing..

11. Know all number conversions-hexa-dec, oct-dec,.

12. Many problems like A needs 5 resources and B needs 6 resources of same type, then minimum resources needed so that deadlock will not occur?

13. Know to calculate waiting and turn around time

14. Size of the RAM required to find square of 4-bit no?

15. If x0=1 using Newton Raphson method,find x1 for x2 -1 =0?

16. Know the difference between first/second order and linear/non-linear differential equations?

17. Which one is a star LAN? a

**Answer : **10BaseT

18. In which 8B/6T encoding used?

**Answer : **100BaseT4

19. MS-DOS a) completely multiprogramming b)partially multiprogramming c) not a multiprogramming

20. A task is divided and computed in different processor is

**Answer : ** Distributed processing

21. Token Ring is

**Answer : ** 802.5

22. When token reached the intended recipient,then what it does?

**Answer : ** >It recognizes its address, >copies the message, >checks for error, >changes 4 bits in the last byte of frame to indicate address recognized and frame copied.

23. Which one has the common database?

**Answer : ** link state

24. Hamming code related problems like minimum bits required for error detection

25. What addressing used in network layer?

**Answer : **logical addressing

26. A question was from TDM bus relating RAM (have a look on it)

27. Know what a microprogram and microcomputer ?

28. If the quantum size of RR increases then turn around time

**Answer : ** increases(chk)

29. Questions like no of page frames replace using FIFO.

30. Questions from set associative mapping (numericals)

31. Know the range for sign –magnitude, 1’s complement, 2’s complement for n-bit no.?

32. no. of address lines in ROM is determined by

**Answer : ** no. of input lines

33. Have a look on advantages and disadvantages of GO-BACK N ARQ and Selective Reject

34. Memory protection is of no use in a) Single user system b) multiprogramming………

35. Auto variables when uninitialized will have

**Answer : **Unpredictable (garbage) value

36. Chart used for Scheduling

**Answer : **gantt chart