Sunday 30 December 2012

STLD jntuh unit-1 bits



                                               STLD

                                                   FIRST MID JNTUH ONLINE BITS    
            
                                        UNIT-1(Number systems and codes)

Section-I :  choose the correct answer

 1. The fraction (0.68)10 is equal to [        ]
a) (0.010101)2 b) (0.101)2 c) (0.10101)2 d) (0.10111)2

2. The Hexadecimal number A0 has the decimal value [    ]
a)80 b) 256 c) 100 d) 160

3. Given two numbers A & B in sign magnitude representation in an eight bit format A=00011110 & B=10011100,   A XOR B gives [    ]
a)10000010 b) 00011111 c) 10011101 d) 11100001

4. The value of binary 1111 is [ ]
a) 23-1 b) 24-1 c) 24 d) none of these

 5. The minimum number of bits required to represent negative numbers in the range of -1 to -11 using 2’s complement arithmetic is [ ]
(a)2 (b) 3 (c) 4 (d) 5

6. The following code is not a BCD code. [ ]
a)Gray code (b) Xs-3 code (c) 8421 code (d) All of these

7. A 15-bit hamming code requires [ ]
(a)4 parity bits (b) 5 parity bits (c) 15 parity bits (d) 7 parity bits

 8.If=5,the base(radix) of the number system is [ ]
a)5 (b) 6 (c) 7 (d) 8

9. The hexadecimal number system is used in digital computers and digital systems to [ ]
(a) Perform arithmetic operations (b) Perform logic operations (c) Perform arithmetic and logic operations (d) Input binary data into the sys

10.  Determine the value of base x  if : (211)x = (152)8 [ ]
(a) 2 (b) 10 (c) 8 (d) 7

11.  Determine the value of base x, if (193)x = (623)8 [ ]
(a)16 (b)4 (c)2 (d)5

12.  Which of the following are called Universal gates [ ]
(a) NAND,NOR (b) AND,OR (c) XOR XNOR (d) OR,XOR

Section-II: Fill in the blanks

18. Cyclic codes are also called ________________codes

19. The basic two types of BCD codes are _______________and________ codes.

20. The distance between code words 10010 & 10101 is ________.

21. Convert the binary code (110110)2 to Gray code_____________.

22. Conversion of 0.1289062 decimal number to its hexa equivalent is ________.

23. In b’s complement method, the carry is ______ and in(b-1)’s complement method the carry is _______

24. The MSB of a binary number has a weight of 512,the number consists of _________ bits.

25. __________ are codes which represent letters of the alphabets and decimal numbers as a sequence of 0s and 1s.
 
                                                                                                                Prepared by
                                                                                                              Srilatha & Sowmya