Question Bank No: 1

1. A statement among the following is,

 a)Every rectangle is a parallelogram
 b)Who is the father of geometry?
 c)Is 1a a prime number?
 d)Sit down.

2. Of the following, the one which is not a statement is,

 a)2+3=4
 b)Moon revolves around the sun
 c) 6 has four different prime factors
 d)Read the question carefully.

3. A statement with truth value F is ,

 a)Between two distinct rational numbers, there are infinitely many irrational numbers.
 b)Every nonempty finite set of integers contains a smallest number
 c)Every non-empty set of real numbers contains a smallest number.
 d)every non-empty finite set of integers contains a smallest number.

4. The statement with truth value T is,

 a)A prime number greater than 100 is odd
 b)The intersection of two nonempty sets is none mpty
 c)Between two distinct natural numbers, there is a natural number.
 d)4 is aprime number

5. If p and q are two statements, then a statement with truth value T is,

 a)p q
 b)pq
 c)p q
 d)qq

6. If p and q have truth value T and r has truth value F, then,

 a)(pr) q has truth value F
 b)(qr) p has truth value F
 c)(pq) r has truth value T
 d)None of these

7. If the truth value of p and q are T and F respectively then,

 a)(pq) has truth value T
 b)(pq) has truth value F
 c)(pq) (pq) has truth value T
 d)None of these

8. Each of the statements pq. qr and ~ r is true, then

 a)p is true
 b)p is flase
 c)q is true
 d)none of these.

9. If p,q are two statements , then

 a)~(pq) = ~p ~q
 b)~(pq) = ~p~q
 c)~(pq) = pq
 d)~(pq) =p~q

10. If p,q,r, are statements such that p ~q and r ~s, then (p r) (qs) =

 a)t
 b)c
 c)ps
 d)pr

11. The truth value of the following two statements
1. "Complex numbers are real numbers if and only if all squares are rectangles"
2. " Hydrogen is a gas if and only if iron is not a metal" are respectively"

 a)F,F
 b)F,T
 c)T,T
 d)T,F

12. Which of the following is not true ? The conditionla statements pq means

 a)if p then q
 b)q if p
 c)p only if q
 d)q is necessary for p

13. The negation of pq is

 a)(~pq) (~qp)
 b)(~pq) (~qp)
 c)(~pq) (~qp)
 d)(~pq) (~qp)

14. The dual of the statement p~ p = c is

 a)p ~p = c
 b)p~p = t
 c)p~p = t
 d)p~p = c

15. Each of the statments pq,~rq and p is true. Then

 a)r is false
 b)r is true
 c)q is true
 d)pq is true

16. pq) (~pq) is,

 a)a tautology
 b)a contradiction
 c)both tautology and contradiction
 d)neither a tautology nor a contradiction

17. If p is the statement '0' is a natural number' and q is the statement '5 is factor of 10' , then

 a)pq and ~pq have truth values T
 b)pq has truth value T and ~pq has truth value F
 c)~p ~q has truth value F
 d)pq has truth value T

18. If p(~pq) is false, the truth values of p and q are respectively,

 a)F,T
 b)F,F
 c)T,T
 d)T,F

19D6 ={1,2,3,6} is a Boolean Algebra w.r.t the operations a+b = lcm of a and b, a.b = gcd of a and b and a' = 6a a, b D6 The multiplicative identity elements is

 a)1
 b)2
 c)4
 d)6

20. The additive element of the Boolean Algebra of logical statements is

 a)t
 b)f
 c)0
 d)none of these

21. Let X be a nonempty setP(X) = {A: AX} is Boolean Algebra w.r.t. the operations A+B = AB, A.B = AB A' = X - A A, B P (X)The additive identity element is

 a)X
 b)φ
 c){φ}
 d){X}

22. In a Boolean algeobra a'.b' =

 a)(a+b)'
 b)(a.b)'
 c)(a'.b')'
 d)a+b

23. In a Boolean algebra, a is not equal to

 a)a.a
 b)a+a
 c)a+a.b
 d)(a'.b')'

24. If B is a Boolean algebra and a,b,cB then a + (b,c) =

 a)(a+b).c
 b)a.c +b.c
 c)(a+b).(a+c)
 d)a

25. If a,b,c B then a+b+a'.b' =

 a)0
 b)1
 c)a'+b'
 d)a+b

26. If a,b,c, B then a.b +c.(a'+b') =

 a)a+b.c
 b)a.b+c
 c)(a.c+b)
 d)(a+b).c

27. In a Boolean algebra B, a.b+a.b'+a' =

 a)a
 b)b
 c)0
 d)1

28. In a Boolean algebra a'+b = 1 then

 a)a=b
 b)a=0
 c)a+b = 0
 d)a.b' = 1

29. In a Boolean algebra (a+b)' + (a'+b')' =

 a)a
 b)b
 c)a'
 d)b'

30. In a Boolean algebra a.b+[(a+b').b]' =

 a)a
 b)b
 c)1
 d)0

31. If x,y B ( a Boolean algebra) then the dual of the statement x+[y'+x).y]'=1

 a)x'+(y+x').y' = 0
 b)x.[(y'.x) + y]' = 0
 c)x'.((y.x') + y') = 0
 d)None of these

32. In a Boolean algebra the dual of the statement x.y'+y = x+y is

 a)x'.y + y' = x'+y'
 b) x'+y.y' = x'.y'
 c)(x+y').y = x'.y'
 d)(x+y').y = x.y

33. In a Boolean algebra x.y.z + x.y'.z' is equal to

 a)x.(y.z')'
 b)x.(y'.z)'
 c)x.(y'+z)
 d)x.y.z

34. The value of the Boolean expression (x.y + x'.z). (x+y.z) in the Boolean algebra of switching circuits is =

 a)1 if x = 1, y = 1, z= 1
 b)if x = 1, y = 0 z= 0
 c)if x = 0, y = 0, z= 1
 d)if x = 1, y = 0, z= 1

35. The Boolean polynomial representing the circuitis
q11-35Can be simplified to

 a)(a+c.b').(b+c')
 b)a.(c+b')+b.c'
 c)a.(c+b').(b+c')
 d)(a+b+c').(c+b')

36. The Boolean polynomial representing the circuit
q11-36 is

 a)p.q + (q'+r') + p'.r
 b)(p+q).(q.r').(p'+r)
 c)p.q+q'.r'+p'.r
 d)p+q+q'+r'+p'+r

37. If a,b,B then a+a.b =

 a)a+b
 b)a.b
 c)a
 d)b

38. Boolean expression corresponding to the following combinatorial circuit is
q11-38equal to

 a)( x1. x2).(x1'.x2)
 b) (x1.x2) (x2'.x2)
 c)(x1x2) . (x'1+x2)
 d)all the above

39. The Boolean function of the combinatorial gate
q11-39is

 a)f(x,y,z) = ( x'+y').z
 b)f(x,y,z) = (x.y)' + z
 c)f(x,y,z) = (x.y) +z'
 d)f(x,y,z)=(x+y)'.z

40. The Boolean expression for the output of the logic circuit
q11-40

 a)(x+y)'+x
 b)(x.y)'+x
 c)(x.y)'.x
 d)d'.y'+x

41. If x,y, z are three elements of a Boolean algebra then (x+y).(y+z).(z+x) =

 a)2x.y.z
 b)x.y+y.z+z.x
 c)(x+y+z)2
 d)x+y+z

42. 42.The circuit(p.q')+(p.q.r)+ (p'.r) is equal to

 a)(p+r).r
 b)(p'+q).r
 c)(p'+q').r
 d)(p.q')+r

43. If x,y are any two element of a Boolean algebra, then (x+y).(x+y').(x'+y) is equal to

 a)x+y
 b)x.y
 c)x'+y
 d)x.y'

44. The Boolean expression corresponding to the combinatorial circuit
q11-44can be simplified to

 a)x2
 b)x1+ x'2
 c)x'1+ x2
 d)x1+ x2

45. The circuit A.(B+C).B. (b+C') is equivalent to

 a)A.B.C'
 b)A.C'
 c)A.B'
 d)AB

46. The switching circuit (A+C).(A'+B)+C.(B'+C') is equivalent to

 a)A.B+C
 b)A.C+B
 c)B.C+A
 d)A+B+C

47. The circuit (A+B).(B'+C)+(B+C).(A'+C') is equivalent to

 a)A.B+C
 b)A.C+B
 c)B.C+A
 d)A+B+C

48. In a Boolean algebra a.b.c' + a.b'.c+a.b'.c' =

 a)a.b.c'
 b)a.(b+c)
 c)a.(b'+c')
 d)a.(b+c')

49. There is no Boolean algebra containing exactly n elements where

 a)n = 2
 b)n = 3
 c)n= 4
 d)n= 8

50. The number of possible switching circuits with three switches is

 a)2
 b)3
 c)4
 d)5