5. The boolean function A + BC is a reduced form of
Correct : B. (a + b)(a + c)
6. A is a circuit with only one output but can have multiple inputs.
Correct : A. logic gate
7. There are 5 universal gates.
Correct : B. false
8. The Output is LOW if any one of the inputs is HIGH in case of a gate.
Correct : B. nand
9. The complement of the input given is obtained in case of:
Correct : C. not
10. How many AND gates are required to realize the following expression Y=AB+BC?
Correct : D. 2
11. Number of outputs in a half adder
Correct : B. 2
12. The gate is an OR gate followed by a NOT gate.
Correct : C. nor
13. The expression of a NAND gate is
Correct : C. (a.b)’
14. Which of the following correctly describes the distributive law.
Correct : B. (a+b).c=ac+bc
15. The logical sum of two or more logical product terms is called
Correct : A. sop
16. The expression Y=(A+B)(B+C)(C+A) shows the operation.
Correct : B. pos
17. The canonical sum of product form of the function y(A,B) = A + B is
Correct : B. ab + ab’ + a’b
18. A variable on its own or in its complemented form is known as a
Correct : B. literal
19. Maxterm is the sum of of the corresponding Minterm with its literal complemented.
Correct : A. terms
20. Canonical form is a unique way of representing
Correct : C. boolean expressions
21. There are Minterms for 3 variables (a, b, c).
Correct : C. 8
22. expressions can be implemented using either (1) 2-level AND- OR logic circuits or (2) 2-level NAND logic circuits.
Correct : C. sop
23. There are cells in a 4-variable K- map.
Correct : B. 16
24. The prime implicant which has at least one element that is not present in any other implicant is known as
Correct : A. essential prime implicant
25. Product-of-Sums expressions can be implemented using
Correct : D. both 2-level or-and and nor logic circuits
26. Each product term of a group, w’.x.y’ and w.y, represents the in that group.
Correct : C. sum-of-minterms
27. It should be kept in mind that don’t care terms should be used along with the terms that are present in
Correct : A. minterms
28. Using the transformation method you can realize any POS realization of OR-AND with only.
Correct : D. nor
29. In case of XOR/XNOR simplification we have to look for the following
Correct : D. both diagonal and offset adjencies
30. In which of the following gates the output is 1 if and only if at least one input is 1?
Correct : D. or
31. The time required for a gate or inverter to change its state is called
Correct : C. propagation time
32. Odd parity of word can be conveniently tested by
Correct : D. xor gate
33. The number of full and half adders are required to add 16-bit number is
Correct : B. 1 half adders, 15 full adders
34. An OR gate can be imagined as
Correct : B. switches connected in parallel
35. In parts of the processor, adders are used to calculate
Correct : D. all of the mentioned
36. How many full adders are required to construct an m-bit parallel adder?
Correct : C. m-1
37. In which operation carry is obtained?
Correct : B. addition
38. If A and B are the inputs of a half adder, the sum is given by
Correct : C. a xor b
39. If A and B are the inputs of a half adder, the carry is given by
Correct : A. a and b
40. Half-adders have a major limitation in that they cannot
Correct : C. accept a carry bit from a previous stage
41. The difference between half adder and full adder is
Correct : C. half adder has two inputs while full adder has three inputs
42. If A, B and C are the inputs of a full adder then the sum is given by
Correct : C. a xor b xor c
43. If A, B and C are the inputs of a full adder then the carry is given by
Correct : A. a and b or (a or b) and c
44. How many AND, OR and EXOR gates are required for the configuration of full
Correct : B. 2, 1, 2
45. Half subtractor is used to perform subtraction of
Correct : A. 2 bits
46. How many outputs are required for the implementation of a subtractor?
Correct : B. 2
47. Let the input of a subtractor is A and B then what the output will be if A = B?
Correct : A. 0
48. Let A and B is the input of a subtractor then the output will be
Correct : A. a xor b
49. Let A and B is the input of a subtractor then the borrow will be
Correct : B. a’ and b
50. What does minuend and subtrahend denotes in a subtractor?
Correct : C. its inputs
51. Full subtractor is used to perform subtraction of
Correct : B. 3 bits
52. The output of a full subtractor is same as
Correct : B. full adder
53. The full subtractor can be implemented using
Correct : B. two half subtractors and an or gate
54. Why XOR gate is called an inverter?
Correct : C. it behaves like a not gate
55. Controlled buffers can be useful
Correct : A. to control the circuit’s output into the bus
56. A logic circuit that provides a HIGH output for both inputs HIGH or both inputs LOW is
Correct : A. ex-nor gate
57. What is the first thing you will need if you are going to use a macro-function?
Correct : D. experience in hdl
58. What is the major difference between half- adders and full-adders?
Correct : C. full adders have a carry input capability
59. The binary subtraction of 0 – 0 = ?
Correct : A. difference = 0, borrow = 0
60. How many basic binary subtraction operations are possible?
Correct : B. 4
61. When performing subtraction by addition in the 2’s-complement system
Correct : C. the minuend is left in its original form and the subtrahend is changed to its 2’s- complement
62. What are the two types of basic adder circuits?
Correct : B. half-adder and full-adder
63. Which of the following is correct for full adders?
Correct : D. in a parallel full adder, the first stage may be a half adder
64. The selector inputs to an arithmetic/logic unit (ALU) determine the
Correct : B. arithmetic or logic function
65. The inverter can be produced with how many NAND gates?
Correct : B. 1
66. What are carry generate combinations?
Correct : B. if all of the output are independent of the inputs
67. How many shift registers are used in a 4 bit serial adder?
Correct : C. 2
68. A D flip-flop is used in a 4-bit serial adder, why?
Correct : C. it is used to store the carry output of the full adder
69. What is ripple carry adder?
Correct : A. the carry output of the lower order stage is connected to the carry input of the next higher order stage
70. If minuend = 0, subtrahend = 1 and borrow input = 1 in a full subtractor then the borrow output will be
Correct : B. 1
71. The decimal number system represents the decimal number in the form of
Correct : B. binary coded
72. 29 input circuit will have total of
Correct : D. 512 entries
73. BCD adder can be constructed with 3 IC packages each of
Correct : C. 4 bits
74. The output sum of two decimal digits can be represented in
Correct : C. bcd
75. The addition of two decimal digits in BCD can be done through
Correct : A. bcd adder
76. 3 bits full adder contains
Correct : D. 8 combinational inputs
77. The simplified expression of full adder carry is
Correct : A. c = xy+xz+yz
78. Complement of F’ gives back
Correct : B. f
79. Decimal digit in BCD can be represented by
Correct : D. 4 input lines
80. The number of logic gates and the way of their interconnections can be classified as
Correct : A. logical network
81. What is a multiplexer?
Correct : B. a multiplexer is a device which converts many signals into one
82. Which combinational circuit is renowned for selecting a single input from multiple inputs & directing the binary information to output line?
Correct : A. data selector
83. It is possible for an enable or strobe input to undergo an expansion of two or more MUX ICs to the digital multiplexer with the proficiency of large number of
Correct : A. inputs
84. Which is the major functioning responsibility of the multiplexing combinational circuit?
Correct : C. generation of selected path between multiple sources and a single destination
85. 6 MULTIPLEXER
Correct : C. to active the entire chip
86. One multiplexer can take the place of
Correct : D. several ssi logic gates or combinational logic circuits
87. A digital multiplexer is a combinational circuit that selects
Correct : A. one digital information from several sources and transmits the selected one
88. If the number of n selected input lines is equal to 2^m then it requires select lines.
Correct : B. m
89. How many select lines would be required for an 8-line-to-1-line multiplexer?
Correct : D. 3
90. A basic multiplexer principle can be demonstrated through the use of a
Correct : C. rotary switch
91. How many NOT gates are required for the construction of a 4-to-1 multiplexer?
Correct : C. 2
92. In the given 4-to-1 multiplexer, if c1 = 0 and c0 = 1 then the output M is
Correct : B. x1
93. The enable input is also known as
Correct : C. strobe
94. The word demultiplex means
Correct : D. one into many as well as distributor
95. Why is a demultiplexer called a data distributor?
Correct : A. the input will be distributed to one of the outputs
96. Most demultiplexers facilitate which type of conversion?
Correct : B. single input, multiple outputs
97. In 1-to-4 demultiplexer, how many select lines are required?
Correct : A. 2
98. In a multiplexer the output depends on its
Correct : B. select inputs
99. In 1-to-4 multiplexer, if C1 = 0 & C2 = 1, then the output will be
Correct : B. y1
100. In 1-to-4 multiplexer, if C1 = 1 & C2 = 1, then the output will be