Unit 3 - Practice Quiz

ECE249

1 Which of the following represents the decimal number $25$ in binary?

A.
B.
C.
D.

2 Convert the hexadecimal number to its decimal equivalent.

A. $29$
B. $30$
C. $31$
D. $28$

3 What is the decimal value of the binary number ?

A. $5.50$
B. $5.25$
C. $5.75$
D. $5.35$

4 Which of the following is an unweighted code?

A. BCD Code
B. 8421 Code
C. Excess-3 Code
D. 2421 Code

5 Convert the binary number to Gray code.

A. $1011$
B. $1010$
C. $1110$
D. $1100$

6 The Gray code $1011$ represents which binary number?

A.
B.
C.
D.

7 What is the BCD (8421) representation of decimal number $12$?

A. $00010010$
B. $1100$
C. $00001100$
D. $00100001$

8 What is the Excess-3 code for the decimal number $6$?

A. $1000$
B. $0110$
C. $1001$
D. $1100$

9 The 2's complement of the binary number $10110$ is:

A. $01001$
B. $01010$
C. $01011$
D. $10111$

10 In 8-bit 2's complement representation, what is the range of integers that can be represented?

A. -127 to +128
B. -128 to +127
C. -256 to +255
D. 0 to 255

11 Perform the subtraction using 2's complement method.

A.
B.
C.
D.

12 Which logic gate is known as the 'Universal Gate'?

A. AND
B. XOR
C. NAND
D. OR

13 The output of an XOR gate is HIGH only when:

A. Both inputs are LOW
B. Both inputs are HIGH
C. The inputs are different
D. The inputs are the same

14 Which boolean law states that ?

A. Absorption Law
B. Distributive Law
C. Redundancy Law
D. De Morgan's Law

15 According to De Morgan's first theorem, is equal to:

A.
B.
C.
D.

16 A 4-variable K-Map contains how many cells?

A. 8
B. 12
C. 16
D. 32

17 In a K-Map, grouping 4 adjacent $1$s (a quad) eliminates how many variables from the term?

A. 1
B. 2
C. 3
D.

18 The canonical sum of products (SOP) form consists of terms called:

A. Maxterms
B. Minterms
C. Midterms
D. Sumterms

19 Convert the octal number to binary.

A.
B.
C.
D.

20 What is the 9's complement of the decimal number $27$?

A. $72$
B. $73$
C. $82$
D. $28$

21 The boolean expression simplifies to:

A. $0$
B. $1$
C.
D.

22 Which of the following codes is known as a self-complementing code?

A. 8421 BCD
B. Excess-3
C. Gray Code
D. Octal

23 The simplified boolean expression for the K-Map grouping involving corners of a 4-variable map ($0000, 0010, 1000, 1010$) is:

A.
B.
C.
D.

24 The symbol represents which form?

A. Canonical POS
B. Canonical SOP
C. Simplified SOP
D. Standard POS

25 In boolean algebra,

A.
B.
C.
D. $1$

26 Which gate is equivalent to an AND gate followed by a NOT gate?

A. NOR
B. NAND
C. XOR
D. XNOR

27 What is the result of adding binary numbers ?

A. $11000$
B. $10100$
C. $11100$
D. $10010$

28 A digital circuit that produces a logic $1$ output when the input number of $1$s is odd is:

A. XNOR gate
B. XOR gate
C. AND gate
D. OR gate

29 If and , what is the value of ?

A. $0$
B. $1$
C. Indeterminate
D. High Impedance

30 The dual of the boolean expression is:

A.
B.
C.
D.

31 In a 3-variable K-map, the cells and are considered:

A. Diagonal
B. Adjacent
C. Opposite
D. Isolated

32 Which of the following is equivalent to the Boolean function ?

A.
B.
C.
D.

33 Convert the binary fraction to decimal.

A. $0.625$
B. $0.500$
C. $0.725$
D. $0.375$

34 What is the radix of the octal number system?

A. 2
B. 8
C. 10
D. 16

35 The boolean expression is equivalent to:

A.
B.
C.
D.

36 To perform binary subtraction using 1's complement:

A. Add to 1's complement of . If carry generated, add 1 to sum.
B. Add to 1's complement of . If carry generated, ignore it.
C. Add to .
D. Subtract directly.

37 What is the minimum number of NAND gates required to implement an OR gate?

A. 2
B. 3
C. 4
D. 1

38 In K-Map simplification, 'Don't Care' conditions are represented by:

A. 1
B.
C. X
D. Z

39 The Gray code is often used in:

A. Arithmetic operations
B. Shaft position encoders
C. Error correction
D. Floating point operations

40 Which of the following corresponds to the Logic equation ?

A. NAND
B. NOR
C. XOR
D. XNOR

41 What is the 1's complement of $100100$?

A. $011011$
B. $011100$
C. $100101$
D. $011010$

42 Convert decimal $13$ to Excess-3 code.

A. $10000$
B. $01000110$
C. $0100$
D. $1101$

43 The distributive law applies to:

A. Only boolean algebra
B. Only ordinary algebra
C. Both boolean and ordinary algebra
D. Neither

44 If a 3-input NAND gate has inputs , the output is:

A.
B. 1
C. High Impedance
D. Undefined

45 The standard POS form of the expression corresponds to:

A. Sum of Minterms
B. Product of Maxterms
C. Product of Minterms
D. Sum of Maxterms

46 The binary code for Hexadecimal is:

A. $1010$
B. $1011$
C. $1100$
D. $1101$

47 Which theorem allows moving a bubble from the output of an AND gate to the inputs, changing the gate to OR?

A. Consensus Theorem
B. De Morgan's Theorem
C. Duality Theorem
D. Superposition Theorem

48 Overflow in 2's complement addition occurs when:

A. Adding a positive and a negative number
B. Carry out occurs from MSB
C. Adding two numbers of same sign yields a result of opposite sign
D. Always when carry out is 1

49 In a 4-variable K-Map, how are the rows and columns labeled?

A. Binary Sequence ($00, 01, 10, 11$)
B. Gray Code ($00, 01, 11, 10$)
C. Randomly
D. Decimal Order

50 The value of in boolean algebra is:

A. $1$
B.
C.
D.