Computer Science and Information Technology - Digital Logic Design
Exam Duration: 45 Mins Total Questions : 30
The 2's complement representation of -17 is
- (a)
101110
- (b)
111110
- (c)
101111
- (d)
110001
The binary representation of number (12.0625)10 is
- (a)
(1111.000)2
- (b)
(1010.001)2
- (c)
(1100.101)2
- (d)
None of these
The binary representation of number (10)4 is
- (a)
(1101010010000)2
- (b)
(1111000011010)2
- (c)
(101010011000)2
- (d)
(10111111111)2
Binary representatives of number (673.25)10 is
- (a)
(1010100001.1100)2
- (b)
(1010100001.0011)2
- (c)
(11001001001.0101)2
- (d)
(1010100001.1100)2
The binary number (10.10001)2 is equivalent to
- (a)
(2.53125)10
- (b)
(1.7869)10
- (c)
(1.75)10
- (d)
(40.31)8
The binary number (1101101.711)2 is equivalent to
- (a)
(101.875)10
- (b)
(109.89)10
- (c)
(109.835)10
- (d)
(101.111)10
1's and 2 's complement of 1010101 is
- (a)
0101010, 0101010
- (b)
0101010, 0101011
- (c)
0100100, 0101011
- (d)
None of these
Gray code for (45)10 is
- (a)
110011
- (b)
101101
- (c)
111011
- (d)
111100
BCD code for (13)10 is
- (a)
1101 0011
- (b)
1001 0011
- (c)
0001 0011
- (d)
1010 0101
What will be the complement of function x'yz' + x'y'z in product of sum form?
- (a)
(\(x+y+z\left( \bar { x } +y+z \right) \)
- (b)
\(\left( x+y+\bar { z } \right) \left( \bar { x } +y+\bar { z } \right) \)
- (c)
\(\left( x+\bar { y } +z \right) \left( x+y+\bar { z } \right) \)
- (d)
\(\left( x+\bar { y } +z \right) \left( \bar { x } +\bar { y } +\bar { z } \right) \)
What will be the reduced value of function ((AB)' A(AB)' B)?
- (a)
AB + BC
- (b)
BA + AB
- (c)
\(\bar { B } A+\bar { A } \bar { B } \)
- (d)
\(\bar { B } A+\bar { A } B\)
What are the maximum number of Boolean function involving n Boolean variable?
- (a)
n2
- (b)
2n
- (c)
22n
- (d)
\({ 2 }^{ { n }^{ 2 } }\)
All digital circuits can be realized using only
- (a)
Ex-OR gate
- (b)
multiplexer
- (c)
half adder
- (d)
OR gate
The number of half adder and full adder required to add m-bit data is
- (a)
\(\frac { m }{ 2 } \)half adder,\(\frac { m }{ 2 } \) full adder.
- (b)
1 half adder, m-1 full adder
- (c)
16 half adder, 0 full adder
- (d)
4 half adder, 12 full adder
In a J-K flip flop we have J=Q' and K=1. Assuming that flip-flop was initially cleared and then clocked for 6 pulses, the sequence at the output Q will be
- (a)
010000
- (b)
011001
- (c)
010010
- (d)
010101
When two n-bit binary numbers are added the sum will contain at the most
- (a)
n bits
- (b)
(n+1) bit
- (c)
(n+2) bit
- (d)
(n+3) bit
The fraction 0.6810 is equal to
- (a)
(0.010101)2
- (b)
(0.101012)
- (c)
(0.1012)
- (d)
(0.101112)
BCD addition of A(0101) and B(0110) gives
- (a)
1001
- (b)
1011
- (c)
1000
- (d)
None of these
(11011011011)2 = (?)10
- (a)
109.7865
- (b)
109.6875
- (c)
109.688
- (d)
119.08
Which of the following logic expressions is incorrect?
- (a)
\(1\bigoplus 0=1\)
- (b)
\(1\bigoplus 1\bigoplus 0=1\)
- (c)
\(1\bigoplus 1\bigoplus 1=1\)
- (d)
\(1\bigoplus 1=0\)
The maxterm designator of the term \(\bar { A } +B+\bar { C } +D\) is
- (a)
10
- (b)
13
- (c)
05
- (d)
None of these
Decimal digits can be converted to binary format using
- (a)
Decoder
- (b)
Encoder
- (c)
MUX
- (d)
DE MUX
Match the following:
Logic | Function | ||
(a) | \(\bar { X } +\bar { Y } \) | (p) | Sum |
(b) | XY | (q) | NAND |
(c) | \(\bar { X } \bar { Y } \) | (r) | Carry |
(s) | NOR |
- (a)
a-q, b-r, c-s
- (b)
a-q, b-s, c-r
- (c)
a-p, b-q, c-r
- (d)
a-q, b-s, c-r
10th element of base-3 number system is
- (a)
22
- (b)
12
- (c)
100
- (d)
None of these
Which of the following binary numbers is not divisible by (4)?
- (a)
10101010101010
- (b)
111000111000
- (c)
1111000011
- (d)
All of these
Given that \(\bar { A } B+AC+BC+=AB+\bar { A } C\quad then\quad \left( \bar { A } +C \right) \left( B+C \right) \left( A+B \right) \) is equivalent to
- (a)
\(\left( \bar { A } +B \right) \left( A+C \right) \)
- (b)
\(\left( A+\bar { B } \right) \left( \bar { A } +C \right) \)
- (c)
\(\left( A+B \right) \left( \bar { A } +C \right) \)
- (d)
\(\left( A+\bar { B } \right) \left( \bar { A } +C \right) \)
The Boolean expression \(\bar { X } Y\bar { Z } +\overline { XY } Z+XY\bar { Z } +X\bar { Y } Z+XYZ\) can be simplified to
- (a)
\(X\bar { Z } +\bar { X } Z+YZ\)
- (b)
\(\bar { Z } Y+\bar { Y } Z+XZ\)
- (c)
\(XY+\bar { Y } Z+YZ\)
- (d)
\(\bar { X } \bar { Y } +Y\bar { Z } +X\bar { Z } \)
Match the following:
(a) Encoder | 1. One of many |
(b) Demux | 2. Some of many |
(c) Decoder | 3. Many to some |
- (a)
a-1, b-2, c-3
- (b)
a-3, b-1, c-2
- (c)
a-1, b-2, c-3
- (d)
None of these
The 10's complement of a number is (47480)10
The octal equivalent of the answer of above question is
- (a)
(146450)8
- (b)
(63620)8
- (c)
(52520)8
- (d)
None of these
The total number of MUX required to realize mx1 MUX with 2x1 MUX (m>2) is
- (a)
\(\sum _{ i=1 }^{ { \log _{ 2 }{ m } } }{ \frac { m }{ { 2 }^{ i } } } \)
- (b)
\(\log _{ 2 }{ m } \)
- (c)
m-1
- (d)
None of these