Implement Logical Expression MCQ Quiz in தமிழ் - Objective Question with Answer for Implement Logical Expression - இலவச PDF ஐப் பதிவிறக்கவும்
Last updated on Apr 4, 2025
Latest Implement Logical Expression MCQ Objective Questions
Top Implement Logical Expression MCQ Objective Questions
Implement Logical Expression Question 1:
Match the terms in List - I with the options given in List - II :
|
|
List - I |
|
List – II |
|
(a) |
Decoder |
(i) |
1 line to 2n lines |
|
(b) |
Multiplexer |
(ii) |
n lines to 2n lines |
|
(c) |
De multiplexer |
(iii) |
2n lines to 1 line |
|
|
|
(iv) |
2n lines to 2n−1 lines |
Answer (Detailed Solution Below)
Implement Logical Expression Question 1 Detailed Solution
Decoder is a combinational circuit that has ‘n’ input lines and maximum of 2n output lines. Therefore, Decoder - n lines to 2n lines
The multiplexer is a combinational logic circuit designed to switch 1 of several (2n) input lines to a single common output line. Therefore, Multiplexer - 2n lines to 1 line
A de-multiplexer is a device that takes 1 input line and routes it to one of several (2n) digital output lines. Therefore, De multiplexer - 1 line to 2n lines
Implement Logical Expression Question 2:
Following Multiplexer circuit is equivalent to
Answer (Detailed Solution Below)
Implement Logical Expression Question 2 Detailed Solution
Output of MUX:
Y = A′B′C + A′BC′ + AB′C′ + ABC
Y = (A ⊕ B ⊕ C)
Y = ∑(1,2,4,7), difference equation of full subtractor.
Truth table:
|
A |
B |
C |
Sdifference |
Cborrow |
Ssum |
Ccarry |
|
0 |
0 |
0 |
0 |
0 |
0 |
0 |
|
0 |
0 |
1 |
1 |
1 |
1 |
0 |
|
0 |
1 |
0 |
1 |
1 |
1 |
0 |
|
0 |
1 |
1 |
0 |
1 |
0 |
1 |
|
1 |
0 |
0 |
1 |
0 |
1 |
0 |
|
1 |
0 |
1 |
0 |
0 |
0 |
1 |
|
1 |
1 |
0 |
0 |
0 |
0 |
1 |
|
1 |
1 |
1 |
1 |
1 |
1 |
1 |
The output equation of MUX = Y = Sdifference = Ssum
Therefore, multiplexer circuit is equivalent to sum equation of full adder as well as difference equation of a full subtractor
NOTE:
Since it is official ISRO CS 2020 question marks has been given for option 1 and option 4.
.Original 4 is this. "Difference equation of a full subtractor" which is changed to get correct answer
Implement Logical Expression Question 3:
The Boolean function f implemented in the figure using two input multiplexes is:
Answer (Detailed Solution Below)
Implement Logical Expression Question 3 Detailed Solution
Output of MUX 1 is select line of MUX 2
Output of MUX 1: B̅.C + B.C̅
Output of MUX 2 is f
Implement Logical Expression Question 4:
Which of the following sets of components is/are enough to implement any arbitrary Boolean functions?
I. 2 to 1 multiplexers
II. NAND gates
III. OR gate, NOT gate
IV. XOR gate, NOT gate
Answer (Detailed Solution Below)
Implement Logical Expression Question 4 Detailed Solution
- Functionally complete operations set is a set of logic function from which any arbitrary Boolean logic function can be realized.
- Examples of functionally complete operation set are:
- OR gate, NOT gate
- AND gate, NOT gate
- NOR gate
- NAND gate
- 2:1 MUX
- Any super set of the above examples will also form functionally complete operations set.
Implement Logical Expression Question 5:
Consider the two cascaded 2-to-1 multiplexers as shown in the figure:
The minimal sum of products form of the output X is
Answer (Detailed Solution Below)
Implement Logical Expression Question 5 Detailed Solution
Output of MUX 1 =
Output of MUX 2 =
Note:
According to option answer should be: Q’R + P’Q + PQR
But we can further minimized it to:
Q’R + P’Q + PQR
=Q’R + Q (P’+ PR)
=Q’R + Q (P’+ R)
=Q’R + P’Q + QR
Implement Logical Expression Question 6:
In a cascaded MUX, we set select line S to high. Then F (A, B) =
Answer (Detailed Solution Below)
Implement Logical Expression Question 6 Detailed Solution
On selecting S=1
Output of 1st MUX:
S̅.A + S.B = 0.A + 1.B = B
B is select line of 2nd MUX
output of 2nd MUX:
F(A,B)= B̅.A + B.S
F(A,B)= B̅.A + B.1
F(A,B)= (B+B̅). (A + B) \\by distribution
∴ F( A,B) = A+B
Implement Logical Expression Question 7:
The minimum Boolean expression for the following circuit is
Answer (Detailed Solution Below)
AB + AC + BC
Implement Logical Expression Question 7 Detailed Solution
A(B + C) + AB + (A + B)C
= AB + AC + AB + AC + BC
= AB + AC + BC
Implement Logical Expression Question 8:
Find the minimum number of MUX needed to implement 64 x 1 MUX using 4 x 1 MUX?
Answer (Detailed Solution Below)
Implement Logical Expression Question 8 Detailed Solution
Data:
M = 64, N = 4
Fomula:
L ≥ logNM
L = The number of levels of connection required.
Calculation:
∴ L ≥ 3
Lmin = 3
∴ the minumum level required for 4 x 1 MUX = 3
Total number of MUX 4 × 1 is
|
Given MUX |
To be implemented |
Required |
|
2 : 1 |
16 : 1 |
8 + 4 + 2 + 1 = 15 |
|
4 : 1 |
16 : 1 |
4 + 1 = 5 |
|
4 : 1 |
64 : 1 |
18 + 4 + 1 = 21 |
|
8 : 1 |
64 : 1 |
8 + 1 = 9 |
|
8 : 1 |
256 : 1 |
32 + 4 + 1 = 37 |
Implement Logical Expression Question 9:
The output f of the 4-to-1 MUX is shown in the figure. The function, f, is given as
Answer (Detailed Solution Below)
Implement Logical Expression Question 9 Detailed Solution
f = S̅1 S̅0 I0 + S̅1 S0 I1 + S1 S̅0 I2 + S1 S0 I3
= x̅ y̅ (1) + x̅ y (0) + x y̅ (0) + xy (1)
= x̅ y̅ + xy
Implement Logical Expression Question 10:
The Boolean function f implemented in the figure using two input multiplexes is:
Answer (Detailed Solution Below)
Implement Logical Expression Question 10 Detailed Solution
Output of MUX 1 is select line of MUX 2
Output of MUX 1: B̅.C + B.C̅
Output of MUX 2 is f