DIGITAL FUNDAMENTALS
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1. The number of levels in a digital signal is --------------- (two)
2. In any flip-flop, when the Q output is 1,the state of the Q’ terminal is -------( 0 )
3. Decimal 15 in binary system can be written as ---------- (1111)
4. If 4 in the binary system is 100 then 8 will be------ (1000)
5. Binary 1010 in decimal system is equivalent to ---------(10)
6. Binary 1111 when subtracted from binary 11111,the result is-----(10000).
7. Binary 1111 when added to binary 11111 is-------- (101110)
8. Binary 1000 multiplied by binary 1000 gives--------(1000000)
9. The decimal form of binary 0.0111 is ---------(0.4375)
10The decimal equivalent of the binary number 10110.0101011101 is ------ (22.3408203125)
11.Binary 101010 is equivalent to decimal number ------------(42)
12.Decimal number 5436 when converted into 9’s complement will become---(4563)
13.Decimal number 1932 when converted into 10’s complement will become----(8086)
14.Decimal 45.15 when converted into 9’s complement will become--------(54.84)
15. Decimal 18.293 when converted into 10’s complement will become--------(81.707)
16.Binary numbers that can be stored in a register consisting of 6 switches are ----(64)
17. BCD numbers that can be stored in a register consisting of 12 switches using an 8,4,2,1 code is ----------(1000)
18.The hexadecimal number B6C7 is equivalent to decimal number--------(46791)
19.The hexadecimal number 64AC is equivalent to decimal number--------(42130)
20. The hexadecimal number A492 is equivalent to decimal number--------(42130)
21.The binary number 101101 is equal to octal number--------(55)
22.Binary number 1011 when converted to its 1’s complement will become----(0100)
23. Binary number 1011. 01 when converted to its 2’s complement will become----(0100.10)
24. The binary number 0111011011 is equivalent to decimal number-------(474)
25. The decimal number 4429.625 is equal to octal number----------(10515.5)
26. 10 in BCD code is represented as-------(0001 0000)
27. Octal 16 is equal to decimal -----(14)
28. (1001-10) is equal to-------(7)
29. The binary number 101100.110 in octal number will be-------(154.6)
30. The binary sum of 111010 and 11011 is ------------(1010101)
31 In decimal system the base or radix is------------(10)
32. The decimal equivalent of the hexadecimal number E5 is--------(229)
33. In 8421 Binary coded Decimal system the decimal number 237 is represented by------ (001000110111)
34. In the 8421 BCD code,the decimal number 125 is written as----------(1111101)
35. In a decimal digital computer,the number 127 is stored as---------(1111111).
36.The logic gate---------- is similar to the function of two series switches.(AND)
37. The logic gate---------- is similar to the function of two parallell switches.(OR)
38. In a NAND gate the output low only when both inputs are--------(high)
39. According to Boolean algebra 1+X is---------( 1 )
40. According to Boolean algebra X+X’ is ----------(1)
41. According to Boolean algebra X+XZ is ---------(X)
42. According to Boolean algebra 1+A+B+C ------------(1)
43. (A+B’+A’B) is same as -----------(1)
44. A(A+B) is same as -------------(A+AB)
45.Three Boolean operators are AND,OR and ----------(NOT)
46 If A=0,B=0,then A’B’ is ---------- (0)
47.The Boolean function for the AND gate is--------(A.B=Y)
48. The Boolean function for the OR gate is--------(A+B=Y)
49. The Boolean function for the NOT gate is--------(A’=Y)
50. The Boolean function for the NAND gate is--------((A.B)’=Y)
True or False
1. Logic gate AND is similar to the function of two series switches.(T)
2. The logic gate NOR is similar to the function of two parallell switches.(F)
3. A(A+B) is same as (A+AB) (T)
4. Three Boolean operators are AND,OR and NOT (T)
5. According to Boolean algebra X+XZ is X. (T)
6. The pulse interval is 1 microsecond.(T)
7. RAM is a temporary memory.(T)
8. four flipflop circuits are needed to divide by 16.(T)
9. six flipflops are needed for a 4 bit counter.(F)
10. A/D converter has a binary input. (F)
11. A toggle operation is used with a flipflop.(T)
12. The complement of AB+B’C+CD’ is A’C’+BC’+A’BD.(T)
13. The variables in booleean algebra can takeany number of values.(F)
14. Boolean expression for NAND gate is A+B+C=Y
15. A logic circuit corresponding to ‘+’ sign is AND gate.(F)
16. The total number of Boolean function which can be realized with 4 variables is 256 (F)
17. The digit 0 with carry of 1 is the sum of binary addition 0+1 (F)
18. The radix of a hexadecimal system is 3.(F)
19. Octal 16 is equal to decimal 16.(D)
20. In decimal system the base or radix is10.(T)
21. The high voltage level of a digital signal in positive logic is i.(T)
22. Flipflop has two stable states.(T)
23. To obtain 1’s complement each bit is subtracted by 1.(T)
24. The addition of 2’s complement of a number is equivalent to subtraction.(T)
25. A 1 in the sign bit is used to represent a negative number.(T)
26. A 0 in the sign bit is used to represent a negative number.(F)
27. In computer representation sign bit has also been included.(T)
28. In BCD code a decimal number is represented by four binary bits.(T)
29. A hexadecimal digit is represented by four binary bits.(T)
30. In binary system there are only 2 digits 0 & 1.(T)
31. The manipulation of binary information is done by logic circuits known as logic gates.(T)
32. The logical operation of AND gate is called AND operation.(T)
33. AND,OR & NOT gates are called logic gates.(T)
34. An OR gate is also known as INCLUSIVE OR gate.(T)
35. NOT gate is called INVERTOR.(T)
36. The NAND is sometimes called universal operation.(T)
37. The output of AND gate is A+B.(F)
38. The abbreviation of NOR is NOT OR.(T)
39. The abbreviation of NAND is NOT AND.(T)
40. The XNOR operation is the complement of XOR operation.(T)
41. An RS Flipflop can be realized by connectin two NOR gate.(T)
42. The flipflop in the simplest form is called latches.(T)
43. An SR flipflop has two input,S and R.(T)
44. The number of output states of a counter is called modulus of a counter.
45. In a ripple counter a decoding gate is used.(T)
46. A presettable counter starts counting from a number greater than 0.(T)
47. The counter which count downward towards lower numbers are down counter.(T)
48. The variables which have only 2 values are called Boolean variables.
49. The Kmap method is a graphical method.(T)
50. D flipflop has 2 inputs.(F)
