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JNTU ONLINE EXAMINATIONS [Mid 2 - NNFL]

The weight updation in extended delta rule is

Wi= (tj-yj)xi f. (y-in j)a.

Wij= (tj-yj) f (y-in j)b.

Wij= xi f.(y-in j)c.

Wij=(tj-yj)xid.

1.

The squared error for particular training pattern if extended delta rule is= m j=1 (tj-yj)

2a.

=m

j=1 (tj+yj)2

b.

=mj=1 (tj)

2c.

=m

j=1 (yj)2

d.

2.

The connection matrix W=

k=1..a Ak BkTa.

k=1..a Akb.

k=1..a Bk Tc.

k=1..aAkBkd.

3.

The Auto associative net training is often called asStoring the vectorsa.

Sorting the vectorsb.Recalling the vectorsc.Searching for the vectorsd.

4.

Two vectors a and b are orthogonal ifi ai=0a.

i bi=0b.

i ai bi =0c.

i ai bi =1d.

5.

The following rule allows for an arbitrary differentiable activation function to be applied to the outputunits

Deltaa.Extended Deltab.Hebbc.

Hopfieldd.

6.

The updation of the following is done to reduce the difference between the computed output and thetarget

Inputa.Outputb.Targetc.Weightd.

7.

Representation of data (-1,+1) is calledBipolara.Binaryb.Real valuedc.Bilineard.

8.

The performance of the auto associative memory net is among the following for bipolar vectors than

the binary vectorsWorsta.Betterb.Equalc.No way relatedd.

9.

Important criterion for an associative network is among the following it can storeTime to traina.Number of patternsb.Iterationsc.Zero elementsd.

10.

The following rule can be used for both binary as well as bipolar vectorsHebb rulea.LVQb.

11.

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LMSc.Winner Ruled.

The weight determination formula in associative memory is

W=p=1..pST (p) t(p)a.

W=p=1..pS(p) t(p)b.

W=p=1..pST (p)c.

W=p=1..p

t(p)d.

12.

The following rule changes the weight of the connection to minimize the difference between the net

input to the output units and the target valueDelta Rulea.Hebb Ruleb.LMS Rulec.Adalined.

13.

The following energy points of the Lyapunov surface have to be mapped to desired memory statesMaximuma.Minimumb.Zeroc.Only oned.

14.

The connection matrix W=k=1..a Ak Bk Ta.

k=1..a Akb.

k=1..a BkT

c.

k=1..a Ak Bkd.

15.

The following matrix provides a way to encode associations as memories into a neural networkHebb matrixa.Covariance matrixb.Bilinear matrixc.Inverse matrixd.

16.

The following results if the input vector pair is same as the output vector pairAuto associativea.Hetero associativeb.Bidirectional Memoriesc.Self organizing mapsd.

17.

The following results if the input vector pair is different as the output vector pair

Auto associativea. Hetero associativeb.Bidirectional Memoriesc.Self organizing mapsd.

18.

The following rule for pattern association is an iterative learning ruleDelta Rulea.Hebb Ruleb.LMS Rulec.Adalined.

19.

The Delta Rule for single output unit is given byWj=(t-yin)xia.

Wj=(t-yin)b.

Wj= (t-yin)xic.

Wj=(yin)xid.

20.

When an axon of cells excite(s) cell B and repeatedly or persistently takes part in firing it, somegrowth process or metabolic change takes place in one or both cells so that A s efficacy as one of thecells firing B is

Increaseda.Decreasedb.Equalc.No way relatedd.

21.

The following is process of forming association between related patternsPattern Associationa.Pattern Classificationb.

Pattern Recognitionc.Pattern Clusteringd.

22.


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The following nets are single layer nets in which the weights are determined to store an asset ofpattern association

Hopfielda.Associative Memoryb.Boltzmann's Machinec.Perceptrond.

23.

The simple and frequently used method for determining the weights for an associative memory neuralnet is

Hebb rulea.LVQb.

LMSc. Winner Ruled.

24.

The following rule assumes that the error signal is directly measurableDelta Rulea.Hebb Ruleb.LMS Rulec.Adalined.

25.

The Delta Rule for single output unit is given byWj=(t-yin)xia.

Wj=(t-yin)b.

Wj= (t-yin)xic.

Wj=(yin)xid.

26.

The Delta Rule for several output units is given by

W ij=(tj-yinj)xia.W ij=(tjxib.

W ij= (tj-yinj)xic.

W ij=xid.

27.

Whether the system is auto associative or hetero associative, the following that are to be associated isstore d in connections of the network

Inputa.Memoryb.Outputc.

Controld.

28.

Following memories can be used as one shot memoriesOLAMa.BAMb.

CAMc. ARTd.

29.

The following has the restrictions on the maximum number of associations it can accurately recallART1a.BAMb.ART2c.Hopfield networkd.

30.

The following BAM is implemented by interconnecting neurons within each layer by means ofadditional weights

Continuousa.Discreteb.Adaptivec.Competitived.

31.

The accretive associative memory is calledAuto associative memorya.Hetero associative memoryb.Hybrid associative memoryc.Hopfield networkd.

32.

The following is a system that provides a mapping from a domain of inputs to a range outputsFundamental memorya.Main memoryb.Additional memoryc.

Associative memoryd.

33.

In associative memory if xk is the input and yk is the output, and when xk yk the process is known as

Auto associativea.

No associativeb.

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Heteroassociativec.Biassociatived.

The following types of BAM are stableContinuousa.Discreteb.Adaptivec.Competitived.

35.

The following network accepts an input vector on one set of neurons and produces a related butdifferent output vector on another set

Hopfielda.BAMb.Boltzmann's machinec.

ART1d.

36.

All BAM's are unconditionally stable for any weight network was proposed byKoskoa.Rumelhartb.McCulloh Pittsc.Kohonend.

37.

In the following system, any neuron is free to change state at any timesynchronousa.asynchronousb.

linearc.nonlineard.

38.

The Bidirectional Associative Memory (BAM) has a neural network of two layers connected with thefollowing system

Unidirectionala.Parallelb.Feedbackc.Feed forwardd.

39.

The BAM is a the following networkauto associativea.Non-associativeb.Heteroassociativec.ARTd.

40.

When E/t 0 the following is obtainedMinimaa.

Maximab. Focus pointc.Trajectoryd.

41.

Energy function of continuous Hopfield net when is a time constant is given as

E = -0.5 i=1..m j=1..m Wij Vi Vj - i.Vi + (1/ ) j=1..m fi-1 (v)dva.

E = -0.25 i=1..m j=1..m Wij Vi Vj - i.Vi + (1/ ) j=1m fi-1 (v)dvb.

E = 0.5 i=1..m j=1..m Wij Vi Vj - i.Vi + (1/ ) j=1..m fi-1 (v)dvc.

E = 0.5 i=1..m j=1..m Wij Vi Vj - iVi + j=1..mfi-1 (v)dvd.

42.

In continuous Hopfield the energy function isE = 0.5 i=1..m j=1..m Wij Vi Vj + i=1..m i.Via.

E = 0.5 i=1..m j=1..m Wij Vi Vjb.

E = 0.5 i=1..m j=1..m Vi Vj + i=1..m i.Vic.

E = 0.5 i=1..m j=1..m Wij j + i=1..m i.Vid.

43.

When the activity of each neuron is formed to change with time, the net is found to convergeaccording to the following differential equation

dUi /dt = -Ui/ + j=1..m Wij Vj - ja.

dUi /dt = -Ui + j=1..m Wij Vjb.

dUi /dt = -Ui/ + Wij Vjc.

dUi/dt = j=1..m Wij Vj- jd.

44.

The following matrix has the property Wij= Wji for i j and Wij=0 for all i

Unit matrixa.Symmetric matrixb.Sparse matrixc.Inverse matrixd.

45.

Continuous valued output functions are used in46.


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Discrete Hopfielda.Continuous Hopfieldb.McCulloh Pittsc.ART-1d.

The connections between the units are bidirectional inBAMa.Discrete Hopfieldb.McCulloh Pittsc.ART-2d.

47.

The Hopfield net can be viewed as anAuto associative BAMa.Hetero associative BAMb.

Boltzmann's machinec.McCulloh Pitts modeld.

48.

Diagonal elements of symmetrical weight matrix of BAM are1a.0b.Non-zeroc.Negative value onlyd.

49.

Lack of the following connections ensure that the networks are conditionally stableInputa.

Feed forwardb.Feed backwardc.

Feed followd.

50.

In the following network an individual unit doesn t connect to itselfHopfielda.BAMb.Boltzmann's matrixc.ART1d.

51.

a.b.c.d.

52.

R ( i,j) = 0 in the relation matrix if (x, y) Ra.Doesn't belongs to Rb.

1c. Equald.

53.

Max Min composition T for relation matrix is defined asT ( x,z) = y Y Max ( Min (R (x,y), S(y,z)))a.T ( x,z) = y Y Min ( Min (R (x,y), S(y,z)))b.T ( x,z) = y Y Max ( Max (R (x,y), S(y,z)))c.T ( x,z) = y Y Min ( Max (R (x,y), S(y,z)))d.

54.

If A1={a,b} A2={1,2} A3={} then =

a.b.c.d.

55.

R ( i,j) = 1 in the relation matrix if (x, y)

Ra. Doesn't belongs to Rb.1c.Equald.

56.

If n= 5 the relation R (X1, X2) is termed as

Binarya.Ternaryb.

Finitec.Quinaryd.

57.

If the universe of discourse or sets are finite, the n-ary relation can be expressed as anResource Matrixa.Relation Matrixb.Region Matrixc.

58.


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Sparse Matrixd.

If R = {(x,y)/y=x+1, (x,y) X then R={(1,3),(2,3),(3,5)}a.{(1,2),(2,3),(3,4)}b.{(1,1),(1,3),(0,4)}c.{(1,0),(2,0),(3,1)}d.

59.

{(a,b)/a A bB isA x Ba.A Bb.

A Bc.

A Bcd.

60.

If A B and A and B are non empty thenA x B = B x Aa.A x B B x Ab.A x B = c.Ax B = Xd.

61.

Composition of relation R and S are denoted byR o Sa.S + Rb.

R Sc.

R - Sd.

62.

If A contains B then

A is superset of Ba.A is subset of Bb.A is leader of Bc.A is complement of Bd.

63.

The following set of set A is the set of all possible subsets that are derivable from A including Null setPower seta.Subsetb.Supersetc.Null setd.

64.

If a set has no members then it is calledNull seta.Non empty setb.Complement setc.Ideal setd.

65.

A set with single element is calledHamiltona.Planarb.Eulerc.Singletond.

66.

If A is fully contained in B thenA is superset of Ba.A is subset of Bb.A is leader of Bc.A is complement of Bd.

67.

The following set is the which, with reference to a particular context contains all possible elementshaving the same characteristics and from which sets can be formed

Universe of discoursea.

Complementb.Singleton setc.Null setd.

68.

The following is well defined collection of objectsUML diagramsa.Setsb.Venn diagramc.

Figured.

69.

The following diagram is pictorial representations to denote a setGannt charta.DAGb.Venn diagramc.RAGd.

70.


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An element is said to be if a belongs to set ACardinala.Memberb.Siblingc.Childd.

71.

The number of elements in a set is calledChromatic numbera.Cardinalityb.In degreec.Out degreed.

72.

The equation of defuzzified value x in MOM defuzzification method is

x = ( xi M xi)/a.

x

= ( xi M-3 xi)/b.

x = ( xi M+1 xi)/c.

x= ( xi M xi )d.

73.

For a discrete membership function, centre of area is

x=i=1..n xi (xi) /( i=1..n (xi) )a.

x = (xi) /( i=1..n (xi) )b.

x=i=1..n xi /( i=1..n (xi) )c.

x=i=1..n xi (xi) /( i=1..n (xi) )d.

74.

For a discrete membership function, centre of area isx=i=1..n xi (xi) /( i=1..n (xi) )a.

x = (xi) /( i=1..n (xi) )b.

x=

i=1..n xi /( i=1..n (xi) )c.

x=i=1..n xi (xi) /( i=1..n (xi) )d.

75.

In case with more than one element having maximum value firing defuzzification, the following shouldbe taken

Mean value of maximaa.Mean value of minimab.Centroidc.Mode valued.

76.

The following is the largest membership grade obtained by any element in that setIndexa.

Heightb.Degreec.Memberd.

77.

In MOM defuzzification method in continuous case M could be defined as the following where |(x) isequal to height of fuzzy set

M = { x [-C,C]a.M = { x&isin [0,1]b.M = { x&isin [0,0]c.M = { x&isin [1,1]d.

78.

In centre of sums method the defuzzified value x is

x =i=1..N xi k=1..N . k xi/ (i=1..N i k=1..N . k xi)a.

x =i=1..N xi k=1..N . k xi/ ( k xi)b.

x

=

i=1..N xi k=1..N .

k xi/ (i=1..N i k=1..N .

k )c.x*

=i=1..N xi k=1..N . xi /(i=1..N i k=1..N . k xi)d.

79.

A collection of rules referring to a particular system is known asFuzzy databasea.Fuzzy rule baseb.Fuzzy setc.Fuzzy relationd.

80.

Conversion of fuzzy set to single crisp value is calledFuzzificationa.Defuzzificationb.Crispificationc.Decryptographyd.

81.


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Conversion of single crisp value to fuzzy set is calledFuzzificationa.Defuzzificationb.Crispificationc.Decryptographyd.

82.

Most commonly used defuzzification methodCentre of areaa.Centre of sumsb.Centre of gravityc.Mean of maximad.

83.

Number of times overlapping area is counted in centroid method isOnly onea.Twiceb.Thricec.Doesn't count at alld.

84.

Number of times overlapping area is counted in centre of sums method isOnly onea.Twiceb.Thricec.Doesn't count at alld.

85.

The energy function of discrete Hopfield network isE= -0.5 ijj yiyj wij xi yi + Oi yja.

E= ij j yiyj wij xi yi + Oi yjb.

E= -0.25 ij j yiyjwij xi yi + Oi yjc.E= -0.5 ij j yiyj wij xi yjd.

86.

E =-[j (yj wij + xi - iyi]a.

-[j (yj wij)yi]b.

-[j (xi - i )yi ]c.

-[j (yj wij + yi ]d.

87.

The essence of a CAM is to map the following onto a fixed (stable) pointOutputa.Fundamental memoryb.Main memoryc.Additional memoryd.

88.

The energy cannot increase for both positive and negative change in yi , the value of E isless than zeroa.Greater than zerob.Equal to zeroc.Infinityd.

89.

In the following mode of training, all neurons in Hopfield networks fire at random.Stable statea.Outputb.Synchronousc.Asynchronousd.

90.

The change in energy is due to a change in theTime of traininga.State of neuronb.Number of neurons presentc.

Weightd.

91.

If the energy doesn t change with further iteration then the net reachesState equilibriuma.State inequilibriumb.State annealingc.State instabilityd.

92.

The formulation of the following nets shows the usefulness of net as a content addressable memoryDiscrete Hopa.Continuous Hopb.Discrete BAMc.Continuous BAMd.

93.

The function is used to prove the stability of recurrent networkTimea.

94.


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Energyb.Sigmoidc.Pressured.

Four neurons have the following number of probable states.8a.16b.32c.64d.

95.

The fuzziness of the data can be decreased byDecreasing the weighting factor Wa.Increasing the weighting factor Wb.Doesn't change with weighting factorc.

Keeping the weighting factor constantd.

96.

The most famous fuzzy clustering procedure in the literature isk-means algorithma.DB-scan algorithmb.Fuzzy-c-means algorithmc.Gaussian algorithmd.

97.

The sum of memberships of all elements in a cluster is always0a.-1b.1c.Variabled.

98.

The fuzziness of the data can be increased byDecreasing the weighting factor Wa.Increasing the weighting factor Wb.Doesn't change with weighting factorc.Keeping the weighting factor constantd.

99.

Fuzzy clustering can also be termed asOverlapping clusteringa.Exclusive clusteringb.Hierarchical clusteringc.Probabilistic clusteringd.

100.

Fuzzy Classification can be appliedOnly to Fuzzy Dataa.Only to Crisp Datab.

Can be applied to any type of Datac. Only to Graphical Datad.

101.

The main advantage of Fuzzy Classification isFeatures in linguistic forms can be converted to Mathematical valuesa.Features can be modeled with probabilistic functionsb.Features can be modeled directly with block diagramc.Features can be modeled graphicallyd.

102.

Fuzzy classification is implemented usingOnly Crisp logica.Only Fuzzy logicb.Both Crisp and Fuzzy logicc.Only Predicate Logicd.

103.

The weighting factor W Accounts for theFuzziness of dataa.Exactness of datab.Probability of datac.Distinct nature of datad.

104.

Biggest application of fuzzy classification isData mininga.Image Processingb.Geographical information systemc.Medical analysisd.

105.

Limitation of fuzzy classification isLow dimensional dataa.High dimensional datab.Trained datac.Uncertain datad.

106.


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Half tea spoon sugar placed in tea impliesSweetness is 0.5a.Probability of sweetness is 0.5b.Sweetness feature can be modeled with a membership 0.5c.Sweetness feature can be modeled with a membership 0.5 Sweetness is 0.5d.

107.

The classes in fuzzy classification areExacta.Distinctb.Distinct but overlappingc.Only overlappingd.

108.

Fuzzy classification is aDecision based applicationa.

Rule based applicationb.Branching applicationc.Both decision based and rule basedd.

109.

Fuzzy membership functions can beOnly distincta.Only continuousb.Only graphicalc.Can be distinct and continuousd.

110.

The output of the fuzzy classifier is determined by the rule which hasLowest degree of membershipa.Highest degree of membershipb.

0 degree membershipc. Exactly 0.5 membershipd.

111.

The partitioning of data in fuzzy classification is usually carried byClusteringa.Probabilityb.Statistical analysisc.Regressiond.

112.

The goal of fuzzy classification isTo cluster the dataa.To find highest membershipsb.To implement fuzzy logicc.To create category membershipsd.

113.

The use of fuzzy classification to ordinary classification is to get

Fixed range of valuesa. Overlapping range of valuesb.Exact valuesc.Optimal valuesd.

114.

Biggest application of fuzzy classification isData mininga.Image Processingb.Geographical information systemc.Medical analysisd.

115.

If 0 (x) then T (P)

(x)a.

Pb.0c.

1d.

116.

B'=

' O X(x,y)a.

' U X(x,y)b.

' || X (x,y)c.

'd.

117.

Bc (y)=a.b.c.

d.

118.

Absolute fuzzy quantifiers are defined over119.


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Ra.0b.1c.d.

Fuzzy inference also referred to asApproximate reasoninga.Abductive reasoningb.Inductive reasoningc.Default logicd.

120.

The following is a statement which acquires a fuzzy truth valueFuzzy prepositiona.Fuzzy predicateb.

Binary valuec.Real valued.

121.

GMP stands forGeneralized Modus Ponensa.Generalized Modus Potentb.Generalized Modus Pointc.Generalized Modus Potentiald.

122.

GMT stands forGeneralized Modus Taga.Generalized Modus Tollensb.Generalized Modus Thricec.

Generalized Modus Threatd.

123.

(x,y) =x (x,y)a.x (x)b.x (y)c. (x,y)d.

124.

* (x,y)=

Min( (x), (y))a.

Max( (x), (y))b.

Min( (x), (x))c.

Min( (y), (y))d.

125.

(x,y) =

Max ( (x,y), (x,y))a.Min ( (x,y), (x,y))b.1- (x,y)c.1- (x,y)d.

126.

(x,y) =Max ( X (x,y), (x,y))a.Min ( X (x,y), (x,y))b.1- (x,y)c.1- (x,y)d.

127.

c (x,y)=Max ( (x,y), (x,y))a.Min ( (x,y), (x,y))b.1- (x,y)c.1- (x,y)d.

128.

The following is fuzzy set defined on Cartesian product of crisps set X1, X2,Xn where the n-tuple (X1,X2,Xn) may have varying degree of membership with in the relation

Fuzzy Relationa.Crisp Relationb.Cartesianc.Functiond.

129.

o (x,z) =yY Max(Min ( (x,y), (y,z)))a.yY Min(Min ( (x,y), (y,z)))b.

yY Max(Max ( (x,y), (y,z)))c.yYMin(Max ( (x,y), (y,z)))d.

130.

a(x) =131.


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a+ (x)a.a* (x)b.(x)c.(x)-ad.

A(x) =((x))a.(x)b.c. *(x)d.

132.

c = Xa.= Xb.{}c.

Ac

d.

133.

If A={(x1,0.5), (x2, 0.7), (x3, 0)} and {(x1,0.8), (x2, 0.2), (x3, 1)} then is

{(x1,0), (x2, 1), (x3, 0)}a.

{(x1,0.8), (x2, 0.7), (x3, 1)}b.

{(x1,0.1), (x2, 0.1), (x3, 1)}c.

{(x1,1.3), (x2, 0.9), (x3,)}d.

134.

If A={(x1,0.5), (x2, 0.7), (x3, 0)} and {(x1,0.8), (x2, 0.2), (x3, 1)} then is

{(x1,0), (x2, 1), (x3, 0)}a.{(x1,0.5), (x2, 0.2), (x3, 0)}b.

{(x1,0.1), (x2, 0.1), (x3, 1)}c.{(x1,1.3), (x2, 0.9), (x3,)}d.

135.

If A={(x1,0.5), (x2, 0.7), (x3, 0)} and {(x1,0.8), (x2, 0.2), (x3, 1)} then (x2)=

0.1a.0.5b.0.2c.0d.

136.

The product of two fuzzy set and whose membership function defined as . (x)

(x) . (x)a.

(x) + (x)b.

(x) - (x)c.

(x) / (x)d.

137.

If={(x1,0.2), (x2, 0.8), (x3, 0.4)} = {(x1,0.4), (x2, 0), (x3, 0.1)} then .{(x1,0.6), (x2, 0.8), (x3, 0.5)}a.

{(x1,0.08), (x2, 0), (x3, 0.04)}b.

{(x1,0.01), (x2, 1), (x3, 0.03)}c.

{(x1,0.02), (x2, 2), (x3, 0.01)}d.

138.


0.8a.0.5b.

1.3c.1d.

139.


0.2a.0.7b.

0.1c.1d.

140.


0.1a.0.5b.0.2c.0d.

141.

The union of two fuzzy sets and is U is defined with membership function A U N (x) as

min ( A(x),N(x))a.max (A(x),N(x))b.abs ( A(x),N(x))c.log ( A(x),N(x))d.

142.


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If A={(x1,0.5), (x2, 0.7), (x3, 0)} and {(x1,0.8), (x2, 0.2), (x3, 1)} then U (x3)=

0a.0.1b.1c.3d.

143.

The intersection of two fuzzy sets and is is defined with membership function A N (x) as

min ( A(x), N(x))a.max ( A(x), N(x))b.abs ( A(x), N(x))c.log ( A(x), N(x))d.

144.

If A={(x1,0.5), (x2, 0.7), (x3, 0)} and {(x1,0.8), (x2, 0.2), (x3, 1)} then U (x3)=

0.1a.0.5b.

0.2c.0d.

145.

The complement of fuzzy set is a new fuzzy set with the following membership function

(x) = 1- (x)a.

(x) = 1+ (x)b.

(x) = 1* (x)c.

(x) = 1/ (x)d.

146.

If={(x1,0.5), (x2, 0.7), (x3, 0)} then c=

{(x1,0.5), (x2, 0.7), (x3, 0)}a.

{(x1,0.5), (x2, 0.3), (x3, 1)}b.{(x1,0.3), (x2, 0.7), (x3, 0)}c.

{(x1,0.5), (x2, 0.7), (x3, 3)}d.

147.

c(x1) =

0.5a.0.3b.

1c.1.8d.

148.

c (x2) =

0.5a.0.3b.1c.1.8d.

149.

c (x3) =

0.5a.0.3b.1c.1.8d.

150.

If (x) =(x) then the two fuzzy sets and are said to be

Equala.Productb.Unionc.Intersectiond.

151.

()c =

a.

ccb.

cc.

c

d.

152.

()c =

a.

ccb.

cc.

c

d.

153.

c =

Xa.

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= Xb.{}c.

Acd.

If={(x1,0.4), (x2, 0.2), (x3, 0.7)} and =2 then ()2=

{(x1,0.16), (x2, 0.04), (x3, 0.49)}a.

{(x1,0.4), (x2, 0.2), (x3, 0.7)}b.

{(x1,0.2), (x2, 0.1), (x3, 0.1)}c.

{(x1,0.1), (x2, 0.3), (x3, 0.7)}d.

155.

If={(x1,0.4), (x2, 0.2), (x3, 0.7)} and =2 then 2(x3)=

0.16a.0.04b.0.49c.0.01d.

156.

The disjunctive some of two fuzzy set and as is

(c) (c)a.

(cc) (

c)b.

(c) (c

c)c.

(c) (

c)d.

157.

a.(x) =

a+ (x)a.

a* (x)b.

(x)c.

(x)-ad.

158.

A(x) =((x))a.

(x)b.

c.

* (x)d.

159.

Raising the fuzzy set to its second power is calledConcentrationa.Dilutionb.Dilationc.Convolutiond.

160.

Taking the square root of fuzzy set is calledConcentrationa.Dilutionb.Dilationc.Convolutiond.

161.

The difference - =

a.

(c)b.

(c)c.

c

cd.

162.

If= {(x1,0.2), (x2, 0.5), (x3, 0.6)} = {(x1,0.1), (x2, 0.04), (x3, 0.5)} then =

{(x1,0.2), (x2, 0.5), (x3, 0.6)}a.

{(x1,0.1), (x2, 0.5), (x3, 0.6)}b.{(x1,0.2), (x2, 0.5), (x3, 0.5)}c.

{(x1,0.1), (x2, 0.3), (x3, 0.6)}d.

163.

c =

Xa.= Xb.

{}c.

Ac

d.

164.

In the discrete case fuzzy set is defined asA= xiX (xi) /xia.

A= xiX (xi ) /x ib.

A= xiX /xic.

165.


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A= xiX (xi ) * xid.

In the continuous case fuzzy set asA= x (x)/xa.A= x (x)/xb.A= x (x)+xc.A= x (x)*xd.

166.

The following is associated with fuzzy set A such that the function maps every elements of theuniverse of discourse X to the interval [0,1]

Threshold functiona.Membership functionb.Sigmoid functionc.Hyperbolicd.

167.

Mathematically membership function is

=1/(1+x)2a.

=(1+x)2

b.

= x2c.=1+xd.

168.

If ={(x1,0.2), (x2 0.8)} = {(x1,0.6), (x2, 0.8)}, = {(x1,0.2), (x2, 0.8)} then

= a.

` b.

= c.

= 3d.

169.

If ={(x1,0.2), (x2 0.8)} = {(x1,0.6), (x2, 0.8)}, = {(x1,0.2), (x2, 0.8)} then

= a.

b.

= c.

= 3d.

170.

The following sets support a flexible sends of membership of elements to a setFuzzy seta.Logic setb.

Certain setc.Crisp setd.

171.

In the following set theory an element either belong to or doesn t belong to a setFuzzy seta.

Logic setb.Certain setc.Crisp setd.

172.

In the following set theory many degrees of membership are allowedFuzzy seta.Logic setb.Certain setc.Crisp setd.

173.

The following function values need not always be described by discrete valuesMembershipa.Indexb.Positionc.Classd.

174.

If ={(x1,0.2), (x2, 0.8)} = {(x1,0.6), (x2, 0.8)}, = {(x1,0.2), (x2, 0.8)} then= a.

b.

= c.

= 3d.

175.

The following logic had its roots in the theory of crisp setsFuzzy logica.Boolean logicb.Prologc.ELIZAd.

176.

Uncertainty arises due to followingComplete informationa.

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Partial informationb.Clear informationc.Coherent informationd.

The statements of (0 /1) type of handling is termed as the following the domain of fuzzy set theoryCrispa.Lispb.Prologc.ELIZAd.

178.

Crisp logic is ofSingle valueda.Multivaluedb.Ambiguious valuedc.

Non defined valuedd.

179.

Fuzzy logic is ofSingle valueda.Multivaluedb.Ambiguious valuedc.Non defined valuedd.

180.

The following logic is of two valuesCrisp logica.Fuzzy logicb.Bayes logicc.Probability theoryd.

181.

In the following logic truth values are multi valuedCrisp logica.Fuzzy logicb.Predicate logicc.Prepositional logicd.

182.

The following theory is an excellent mathematical tool to handle the uncertainty arising due tovagueness

Fuzzy set theorya.Crisp logicb.Classical set theoryc.Prepositional logicd.

183.

The following may arise due to partial information about the problemClaritya.

Uncertaintyb. Perfectionc.Unambiguityd.

184.

Classical set theory also termed asCrispa.Lispb.Prologc.ELIZAd.

185.

Number of pictures that can be stored at a time isOnly onea.Twob.Any number of picturesc.It depends on trainingd.

186.

If bipolar patterns are usedP=n/(log2n)a.P=n/(log2n)b.P=2n/(2log2n)c.P=3n/(2log2n)d.

187.

The Hopfield network consists of a set of neurons forming a multiple loop of following system.Unidirectionala.Parallelb.Feedbackc.Feed forwardd.

188.

The magnetic mutual exchange between the alones led to the development ofSimulated annealinga.McCulloh pithsb.Hopfieldc.

189.


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Boltzmann's Machined.

The following network is able to recognize unclear pictures correctlySimulated annealinga.McCulloh Pittsb.Hopfieldc.Boltzmann's Machined.

190.

In Hopfield netOnly one unit updates its activation at a timea.Many unitsb.

Does not update at allc.Activation function is not presentd.

191.

In Hopfield net the number of binary patterns that can be stored and recalled in a net with reasonableaccuracy a given by

P 0.15na.P 0.25nb.P 0.35nc.P 0.5nd.

192.

The following sets have a tendency to stabilize to a local minima rather than global minimaHopfielda.BAMb.Boltzmann's machinec.

ART1d.

193.

In the following network an individual units doesn t connect to itselfHopfielda.BAMb.

Boltzmann's machinec.ART1d.

194.

Simulated annealing, Boltzmann s Machine, Hopfield nets belongs toFeed forwarda.Feedbackb.Feed followc.Adhocd.

195.

The asynchronous discrete time updating of the units allows a function known as [b]Time functiona.Energy functionb.Memory forc.

Signal functiond.

196.

Energy function is also called as the following function to be found for netBoltzmann s Machinea.Lyapnuov functionb.Sigmoid functionc.Threshold functiond.

197.

The following functions proves that the net will converge to a stable set of actuationsBoltzmann's Machinea.Lyapnuov functionb.Sigmoid functionc.Threshold functiond.

198.

Hop field network isFeed forwarda.Feed backb.Feed followc.Adhocd.

199.

In the following mode of training, all neurons in Hopfield networks fire at the same time.Stable statea.Outputb.Synchronousc.Asynchronousd.

200.

If |A| = n then |P (A)|=2na.2nb.

n2

c.n + nd.

201.


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The value of |A| in singleton set A is1a.0b.5c.Depends on the number of elements in Ad.

202.

X= {1,2,3,4,5,6,7} and A= {5, 4,3} then Ac={1,2,6,7}a.{1,2,3,4}b.{6,7}c.{5}d.

203.

If A={a,b,c,1,2} B={1,2,3,a,c} then A B={a,c,1,2}a.{a,b,c}b.{a,c}c.{}d.

204.

Given A={a,b,c,1,2} B={1,2,3,a,c} then A B=

{a,b.c,1,2,3}a.{a,b,c}b.{1,2,3}c.{}d.

205.

The complement of set A is denoted bya.

Ac

b.

and Acc.Ad.

206.

If A B= then the two sets areJointa.Disjointb.Subsetsc.Supersetsd.

207.

If A= {a,b,c,d,e} B={b,d} then A-B={a,c,e}a.{a,c}b.{a}c.{d}d.

208.

If |A| = 4 then |P (A)|=16a.4b.10c.

8d.

209.

A Ac = isCommutativea.Associativeb.Distributivec.Law of contradictiond.

210.

According to Demorgan's laws (AB)c =

Ac B

ca.

A Bc

b.

Ac Bc.

Ac Bcd.

211.

According to Demorgan's laws (AB)c=

Ac Bca.

A Bc

b.

Ac Bc.

Ac B

cd.

212.

Partition on A indicated as (A) is therefore for each pair (i,j)I for ijAi Aj = a.

iJ Ai =Ab.

213.


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iJ Ai =1c.

iJ Ai =0d.

The following on A is defined to a set of non empty subsets Ai , whose union yields the original set APartitiona.Coveringb.Openingc.Closingd.

214.

The following on A is defined to a set of non empty subsets Ai , each of which is pair wise disjoint andwhose union yields the original set A

Partitiona. Coveringb.Openingc.Closingd.

215.

|A| = |i=1..n Ai|=i=1..n|Ai| is

Rule of additiona.Rule of inclusionb.

Rule of exclusionc.Rule of applicationd.

216.

If the subsets are not pair wise disjoint then the following is not applicable on the covering of set ARule of additiona.Rule of inclusionb.Rule of exclusionc.Rule of applicationd.

217.

A B= B A is the following property of set

Commutativea.Associativeb.Distributivec.Idempotenced.

218.

A A = A is the following property of set

Commutativea.Associativeb.Distributivec.Idempotenced.

219.

A (B C) = (A B) (A C) is the following property of set

Commutativea.Associativeb.

Distributivec.Idempotenced.

220.

A E = A is the following property of setCommutativea.Associativeb.Distributivec.Identityd.

221.

A (A B) = A is the following property of set

Commutativea.Associativeb.Distributivec.Law of absorptiond.

222.

If A B, B C then A C isCommutativea.Associativeb.Distributivec.Transitived.

223.

(Ac)c=A is the following propertyCommutativea.Associativeb.Distributivec.Involutiond.

224.

A Ac = E is

Commutativea.Associativeb.

225.


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Distributivec.Law of excluded middled.

In discrete BAM for Binary input vectors, the weight matrix can be determined by the formulaWij= p (2Si(p)-1) (2tj(p)-1)a.

Wij= p (2Si(p)+1) (2tj(p)-1)b.

Wij= p (2Si(p)-1) (2tj(p)+1)c.

Wij= p (2Si(p)+1) (2tj(p)+1)d.

226.

In discrete BAM for Bipolar input vectors, the weight matrix can be determined by the formulaWij= p Si(p) 2tj(p)a.

Wij= p (2Si(p)+1) (2tj(p)-1)b.Wij= p (2Si(p)-1) (2tj(p)+1)c.

Wij= p (2Si(p)+1) (2tj(p)+1)d.

227.

In continuous BAM for binary input vectors the weights are determined by the formulaeWij= p (2Si(p)-1) (2tj(p)-1)a.

Wij= p (2Si(p)+1) (2tj(p)-1)b.

Wij= p (2Si(p)-1) (2tj(p)+1)c.

Wij= p (2Si(p)+1) (2tj(p)+1)d.

228.

Logistic sigmoid activation function in Y layer is given byf(yin j)=1/(1+exp(-yin j)a.

f(yin j)=1+(1+exp(-yin j)b.

f(yin j)=1-(1+exp(-yin j)c.

f(yin j)=1*(1+exp(-yin j)d.

229.

If the net input is equal to the threshold value, the activation function decide toLeaves the activation of that unit to higher valuea.Leaves the activation of that unit to previous valueb.Zeroc.Oned.

230.

The following memory has the capability to transfer the input smoothly and continuously intorespective output in the range between [0,1]

Continuous BAMa.Discrete BAMb.Hetero associative memoryc.

Auto associative memoryd.

231.

The continuous BAM uses the following function as the activation functionStep activation with Zero thresholda.

Step activation with non-zero thresholdb.Logistic sigmoid functionc.Hyperbolic tangent functiond.

232.

If bias is included in calculating the net input in Y layer then f(yin j )f(yin j) =bj+xiWija.

f(yin j) =bj-xiWijb.

f(yin j) = xiWijc.

f(yin j) =bj+Wijd.

233.

Bidirectional associative memory is developed byRumelharta.Wilsonb.Hechtc.Koskod.

234.

BAM isAuto Associative recurrent networka.Hetero Associative recurrent networkb.Hop field networkc.Perceptrond.

235.

Different forms of BAM areOnly binarya.Only Bipolarb.Only continuousc.Binary, Bipolar, continuousd.

236.

The activation function used in discrete BAM isStep activation with Zero thresholda.Step activation with non-zero thresholdb.

237.


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Logistic sigmoid functionc.Hyperbolic tangent function.d.

The continuous BAM was introduced byRumelharta.Neilsonb.McCullohc.Koskod.

238.

The difference between the number of bits in two binary or bipolar vectors x1 and x2 is called

Hamming distancea.Euclidean distanceb.Mean distancec.Varianced.

239.

The average hamming distance between the vectors is1/n [HD(x1,x2)]a.

1/2n [HD(x1,x2)]b.

1/3n [HD(x1,x2)]c.

1/2 [HD(x1,x2)]d.

240.


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JNTU ONLINE EXAMINATIONS [Mid 2 - PED]

Stator voltage Vs is proportional tostator flux/ frequencya.stator flux * frequencyb.stator flux + frequencyc.stator flux - frequencyd.

1.

In cranes and Lifts ______ type of motor is used

Cage motora.wound motorb.special motorc.generatord.

2.

Speed torque characteristics of a slip ring motor are

exponential raisea.exponential decayb.rectangular hyperbolac.

rectangular parabolad.

3.

Synchronous speed of an induction motor inversely proportional toRotor speeda.Number of polesb.Frequencyc.Stator speedd.

4.

Range of slip of an induction motor from stand still to synchronous speed0 to 1a.1 to 0b.

1 to -1c.0 to -1d.

5.

For an induction motor s is slip, fs is the stator frequency then rotor frequency fr is equal to

fs/sa.

fs * sb.

fs + sc.

fs- sd.

6.

In equivalent circuit of an induction motor, if Rr is the rotor value, n is the stator to rotor turns ratio

then the stator referred value is equal to

Rr / na.Rr / n

2b.

Rr + nc.

Rr * n2

d.

7.

In an induction motor for a fan load, s is the slip and K is the torque constant then load torque TL isequal to

K (1/s2)a.

K (1-s2)b.

K (1-s)2c.

K +(1-s2)d.

8.

Find out the speed of induction motor, whose slip is 0.4 and synchronous speed is 1000rpm

500 rpma.

2000 rpmb.1000rpmc.

600 rpmd.

9.

In equivalent circuit of an induction motor, if Rs is the stator value, n is the stator to rotor turns ratio

then the rotor referred value is equal toRs / na.

Rs / n2

b.

Rs + nc.

Rs * n2

d.

10.

The slip is less than zero in

Motoring regiona.Generating regionb.

11.

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Braking regionc.Regenerating regiond.

The maximum torque is independent ofStating resistancea.Maximum resistanceb.Rotor resistancec.Voltaged.

12.

Maximum slip is directly proportional toStator resistancea.

Rotor resistanceb.Maximum resistancec.Voltaged.

13.

When the rotor in stationary, the torque corresponds to the starting torque whenSlip is equal to unitya.Slip is less than unityb.Slip is greater than unityc.Slip is equal to zerod.

14.

Which of the following motor preferred for high starting torque applicationSquirrel cage induction motora.Slip ring induction motorb.Synchronous motorc.

DC Shunt motord.

15.

Synchronous speed is directly proportional toRotor speeda.Number of polesb.

Frequencyc.Stator speedd.

16.

When torque is equal to zeroSlip is equal to zeroa.Slip is equal to unityb.Slip is less than unityc.Slip is greater than unityd.

17.

The torque has a maximum value, calledBreak over torque at slip minimuma.

Break down torque at slip minimumb.Break down torque at slip maximumc.

Break over torque at slip maximumd.

18.

The torque is positive but the speed is negative, so ___________ torque appears as breaking torqueCostinga.Brakingb.Motorc.Pluggingd.

19.

The slip is greater than unityMotoring regiona.Braking regionb.Regenerating regionc.Generating regiond.

20.

What is the disadvantage of an induction motor using stator voltage controllerThe control circuit is very simplea.The input power factor is very lowb.More compact and less weightc.Its response time is quickd.

21.

Slip speed is proportional toVoltagea.Currentb.Frequencyc.Slipd.

22.

Speed control of AC drives can not be achieved by varyingVoltagea.Currentb.

Frequencyc.Efficiencyd.

23.


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Different between synchronous speed and actual speed called asRotor speeda.Slipb.Frequencyc.Slip speedd.

24.

Torque is proportional toVoltagea.Square of its voltageb.Frequencyc.Currentd.

25.

Varying the stator voltage can control the induction motor speed asAbove the rated speeda.

Below the rated speedb.Above and below the rated speedc.Below the slip speedd.

26.

Stator voltage control for speed control of induction motors is suitable fordrive of a cranea.constant load driveb.running if as generatorc.fan and pump drivesd.

27.

By using AC voltage controller, ___________ can be fixed

supply voltagea.currentb.

supply frequencyc. Fluxd.

28.

By using AC voltage controller, ___________ can be fixedSupply voltagea.Currentb.Slipc.Efficiencyd.

29.

What is the advantage of an induction motor using stator voltage controllerPerformance is poora.Operating frequency is lowb.Maximum torque available from the motorc.There is a consideration saving in energyd.

30.

How to measure the speed of an induction motor in closed loop system

Brushesa. Wattmeterb.Tacho-generatorc.Multimeterd.

31.

What is meant by electric driveDrive employing enginesa.Driven by turbineb.Drive employing electric motorsc.Drive by steamd.

32.

In closed loop speed control of an induction motor using stator voltage,Varying phase controla.Varying frequencyb.Varying negative gate currentc.Varying negative gate voltaged.

33.

What is the disadvantages of squirrel cage induction motorStarting torquea.High efficiencyb.Cheaperc.Speedd.

34.

The rotor moves in the same direction as that of the rotating magnetic field to reduced the inducedcurrent according to

Motion lawa.Lenz s lawb.Faraday s lawc.Right hand ruled.

35.

Difference between reference speed and actual speed called asMaximum speeda.

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Rotor speedb.Error speedc.Stator speedd.

With poles = 6, speed is 1000 rpm then with poles = 8, speed is1250 rpma.1500 rpmb.3000 rpmc.750 rpmd.

37.

When the motor speed is equal to the reference speed

Motor torque is equal to the load torquea.Shaft torque is equal to the load torqueb.Maximum torque is equal to shaft torquec.

Stating torque is equal to shaft torqued.

38.

Which device is suitable for fan control applicationPower transistora.Power Diodeb.Triacc.Zener dioded.

39.

What is meant by stator voltage control of squirrel cage Induction motorRotor resistance controla.Slip power recovery controlb.

Stator voltage & supply frequency controlc.Direct torque controld.

40.

Current - limit control scheme is employed to limit the converter and motor currentAbove the safe limit during transient operationa.

Below the safe limit during transient operationb.Both Above the safe limit during transient operation and Below the safe limit during transient operationc.It can not allow the currentd.

41.

When the starting torque can be increased steplessly from its zero value. Such a start is known as__________

Hard starta.Soft startb.Medium startc.Both Hard start and Soft startd.

42.

If the rotor speed becomes greater than synchronous speed, relativeSpeed between the rotor conductor and air gap rotating field reversea.

Speed between the rotor conductor and air gap rotating field forwardb. Both Speed between the rotor conductor and air gap rotating field reverse and Speed between the rotorconductor and air gap rotating field forward

c.

Speed between the rotor conductor and air gap rotating field samed.

43.

During electric braking motor current tends toExceed the safe limita.Below the safe limitb.Both Exceed the safe limit and Below the safe limitc.No current to the motord.

44.

Acceleration and deceleration modes areSteady-state operationa.Transient operationb.Stand still operationc.Motoring operationd.

45.

Drive operates in ____________mode whenever an increase in its speed is requiredAccelerationa.Decelerationb.Brakingc.Powerd.

46.

Closed loop drives requireSlow responsea.Medium responseb.Fast responsec.No responsed.

47.

A special case of plugging occurs when an induction motor connected to positive sequence voltage isdriven by an active load in the reversing direction

Quadrant IVa.

48.


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Quadrant IIIb.Quadrant IIc.Quadrant Id.

Drive operates in ____________ depending on the direction of rotationQuadrant I or IIIa.Quadrant III or IVb.Quadrant III or IIc.Quadrant II or IVd.

49.

When load torque opposes motion, then it works as a motor operating in ___________ depending on

the direction of rotationQuadrant I or IIIa.Quadrant I or IVb.

Quadrant I or IIc.Quadrant II or IIId.

50.

At low frequency where ( V/f ) ratio is increased to keepMinimum torque constanta.Nominal Torqueb.Maximum torque constantc.Fixed torqued.

51.

Frequency control of an induction motor drives employAC voltage controllera.

Semi-converterb.Cycloconverterc.

Chopper converterd.

52.

Variable frequency control of an induction motor, terminal voltage can be considered proportional to

the product ofFrequency and fluxa.Frequency and voltageb.Flux and voltagec.Voltage and torqued.

53.

Variable frequency control of an induction motor, drop in speed from no load to full load isHigha.Mediumb.Smallc.Both High & Mediumd.

54.

Speed control of three phase induction motor, synchronous speed is directly proportional to the

No. of polesa. Supply frequencyb.Resistancec.Currentd.

55.

Any reduction in the supply frequency, without a change in the terminal voltage, causes anDecrease in the air gap fluxa.Decrease in the rotor frequencyb.Increase in the air gap fluxc.Increase in the rotor frequencyd.

56.

In motoring operation, ( V/f ) ratio is increased atHigh frequencya.High fluxb.Low frequencyc.Low fluxd.

57.

Variable frequency control of an induction motor, speed control and braking operation are availablefrom nearly zero speed to

Above the asynchronous speeda.Above the synchronous speedb.Below the asynchronous speedc.Below the synchronous speedd.

58.

The breakdown torque is a function of slip atLow frequencya.High frequencyb.Medium frequencyc.Constant frequencyd.

59.

In Three phase induction motor air gap flux of the machine is kept constant, like aDC series motora.

60.


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DC shunt motorb.DC compound motorc.Both DC series motor & DC shunt motord.

Generally MOSFET is used inLow voltage and low power invertera.High voltage and low power inverterb.High voltage and high power inverterc.Low voltage and high power inverterd.

61.

The voltage source inverter has

High internal impedancea.High internal Resistanceb.Low internal Reactancec.

Low internal impedanced.

62.

The voltage source inverter allows a variable frequency supply to be obtained from aAC supplya.DC supplyb.Both AC supply & DC supplyc.Impedance sourced.

63.

Speed control schemes are available for control of induction motor onStator sidea.Rotor sideb.

Both Stator side & Rotor sidec.Shaft sided.

64.

What is meant by VSISource contains negligible impedancea.

Source contain more impedanceb.It is a variable voltage sourcec.Both Source contain more impedance & It is a variable voltage sourced.

65.

In general, Frequency of rotor currents = Frequency of supply voltage whenSlip = 0a.Slip = 0.5b.Slip = 1c.Slip = -1d.

66.

By using voltage source inverters along with controlled rectifier, _______ is possible

Motoringa.Brakingb.

Either Motoring or Brakingc. Regeneratingd.

67.

The drawback of stepped wave inverter isHarmonics are eliminated at low frequencya.Large harmonics at low frequencyb.Harmonic content in the motor current decrease at low speedc.Both Harmonics are eliminated at low frequency & Harmonic content in the motor current decrease atlow speed

d.

68.

Presence of low frequency harmonics,More losses at all speeda.Less losses at all speedb.No losses at all speedc.Both More losses at all speed & Less losses at all speedd.

69.

The harmonics in the motor current produceTorque pulsationa.Torque harmonicb.No torquec.Both Torque pulsation & Torque harmonicd.

70.

_______________ is produced by air gap flux at one frequency interacting with rotor mmf at adifferent frequency

Harmonic heatinga.Air gap currentb.Harmonic ripplec.Torque pulsationd.

71.

In a current-fed inverter drive, the two control variable areDC link current and frequencya.Frequency and slipb.

72.


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DC link current and slipc.DC link current and voltaged.

Variable stator current control operation, the developed torque depends on the relative distribution ofRotor current and stator currenta.Stator current and magnetizing currentb.Rotor current and magnetizing currentc.Both Stator current and magnetizing current & Rotor current and magnetizing currentd.

73.

The developed torque of the drive can be controlled either byDC link current or Frequencya.

DC link current or Slipb.DC link current or voltagec.Frequency or slipd.

74.

The major advantage of CSI isMore in reliabilitya.Poor in reliabilityb.Slower dynamic responsec.Faster dynamic responsed.

75.

Change of phase sequence of CSI will provide motoring and braking operations in theForward directiona.Reverse directionb.Both Forward direction & Reverse directionc.

Standstilld.

76.

In minimal close loop control system of a CSI, the dc link current and slip areControlled independentlya.Controlled dependentlyb.

Both ( a & b )c.Proportionald.

77.

In acceleration mode, the slip isPositivea.Negativeb.Zeroc.Infinityd.

78.

In voltage / frequency control, maximum torque obtained is ________ with change in slipFixeda.

Variableb.Both Fixed & Variablec.

Zerod.

79.

When the frequency is reduced, the input voltage must be reduced proportionally is called asVoltage controla.Frequency controlb.Current controlc.V/f controld.

80.

The advantage of PWM control inverter-fed induction motor drives isLow switching lossesa.Simple control circuitb.Less harmonic contentc.Both Low switching losses & Simple control circuitd.

81.

The PWM techniques, gain is inversely proportional toPeak voltage of the fundamentala.Peak current of the fundamentalb.Peak value of the modulating wavec.Peak value of the carrier waved.

82.

The PWM techniques, gain is directly proportional toFundamental peak voltagea.Fundamental peak currentb.Fundamental harmonicsc.Both Fundamental peak voltage & Fundamental peak currentd.

83.

Using PWM techniques -----------can be controliedOnly voltagea.Only frequencyb.

Only Currentc.Voltage, frequency and currentd.

84.


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The ratio of peak value of the modulating wave and peak value of the carrier wave is defined asModulating frequencya.Modulating indexb.Modulating wavec.Modulating carrierd.

85.

Modulating index can be varied betweenInfinity to zeroa.Finite to infinityb.Zero to unityc.Unity to infinityd.

86.

An important effect of PWM switching frequency is the generation ofMagnetic noisea.

Voltage noiseb.Frequency noisec.No noised.

87.

The disadvantage of PWM techniques isMore switching lossesa.Low efficiencyb.High current distortionc.Torque mored.

88.

What is mean by SHE-PWM

Small harmonic elimination PWMa.Single harmonic elimination PWMb.

Selective harmonic elimination PWMc. Signal harmonic elimination PWMd.

89.

The PWM techniques reduce theHarmonic heating and torque pulsationa.Torque pulsation and magnetic noiseb.Acoustic noise, Harmonic heating and torque pulsationc.Switching losses and efficiencyd.

90.

The closed loop speed control drive uses a PWM inverter fed from a dc source, which has capability forOnly two-quadrant operationa.One-quadrant operationb.Only three-quadrant operationc.All four-quadrant operationd.

91.

The ratio of peak output phase voltage and maximum possible peak phase voltage is known as

Modulation indexa. Modulation waveb.Modulation factorc.Modulation carrierd.

92.

Cycloconverter drive has applications in high power drives requiring good dynamic response but onlyHigh speed operationa.Standstill operationb.Costing speed operationc.Low speed operationd.

93.

The cycloconverter induction motor drives has fast response because the speed error is corrected atThe maximum available torquea.The minimum available torqueb.Zero torquec.Both The maximum available torque & The minimum available torqued.

94.

Cycloconverter allows ___________supply to be obtained from a fixed voltage and frequency acsupply

Fixed frequency and fixed voltagea.Fixed frequency and variable voltageb.Variable frequency and fixed voltagec.Variable frequency and variable voltaged.

95.

A motor with large leakage inductance is used in order to minimizeDerating and torque pulsationsa.Voltage regulationb.Switching lossesc.Magnetic noised.

96.

The PI-controller is used to getPoor responsesa.

97.


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Poor steady-state accuracyb.Good steady-state accuracyc.Good delay time responsed.

The slip-speed command is set at the maximum negative value, the drive decelerates underMotoringa.Generative brakingb.Regenerative brakingc.Pluggingd.

98.

The output frequency may vary from zero to an upper limit, which is always lower than the input

frequency is called asStep-up cycloconvertera.Step-down cycloconverterb.

Step-up and Step-down cycloconverterc.Chopperd.

99.

The step-down cycloconverter thyristors turn-OFF by usingLine commutationa.Forced commutationb.Load commutationc.Self commutationd.

100.

Compared to conventional rotor resistance control, static rotor resistance control has severaladvantage because of

Smooth and stepless controla.Maintenance is moreb.

Low responsec. Both Maintenance is more & Low responsed.

101.

In motor circuit static frequency changers are used forPower factor improvementa.Improved coolingb.Reversal of directionc.Speed regulationd.

102.

Rotor resistance speed control is used inSquirrel cage Induction motora.Synchronous Motorb.Slip ring Induction Motorc.DC shunt Motord.

103.

The motor normally used for crane travel is

Ward Leonard controlled DC shunt motora. Synchronousb.DC differentially compound motorc.AC slipring motord.

104.

In rotor resistance control of induction motor, the hardness of speed torque characteristicsIncreasesa.Decreaseb.Increases and decreasesc.Remain samed.

105.

The major disadvantage of rotor resistance control isHigh torquea.High efficiencyb.Low torquec.Low efficiencyd.

106.

Maximum Torque of an induction motor occurs at slip (S) is equal toZeroa.Infinityb.Unityc.Rotor resistance/ Rotor reactanced.

107.

Rotor resistance control is employed in-----DC shunt motor drivesa.DC seriesb.Ward Leonard drivesc.Both DC shunt motor drives & DC seriesd.

108.

In using rotor resistance controlStarting torque is lessa.Zero starting torqueb.

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Starting torque is highc.Both Starting torque is less & Zero starting torqued.

Belted wound rotor induction motor are preferred formachine toolsa.gyratory crushersb.belt converterc.water pumpsd.

110.

Slip power recovery scheme air gap power is directly proportional toMechanical output powera.

Slipb.Both Mechanical output power & Slipc.Zero torque powerd.

111.

In Slip Power recovery scheme what is the formula for Pm in terms of slip and PgPm =(1-S)Pga.

Pm =SPgb.

Pg =(1-S)Pmc.

Pg =S Pmd.

112.

Speed control ____________is obtained by controlling the slip-power.Above the synchronous speedAbove the synchronous speeda.Below the synchronous speedb.At zero speedc.Both Above the synchronous speed & Below the synchronous speedd.

113.

Pole changing method of speed control is used inSlip-ring induction motora.Dc shunt motorb.Dc series motorc.Squirrel cage induction motord.

114.

An induction motor operation with an injected voltage in its rotorStator voltage controla.Rotor resistance controlb.Slip power controlc.Variable frequency controld.

115.

Slip power recovery scheme is only suitable forDC shunt motora.Slip-ring induction motorb.Synchronous motorc.

Both Slip-ring induction motor & Synchronous motord.

116.

The principles of slip-power control is particularly popular inWard Leonard I lgener drivesa.Static Kramer drivesb.

Static scherbius drivesc.Both Static Kramer drives & Static scherbius drivesd.

117.

The static Kramer drive cannot haveMotor braking capabilitya.Regenerative braking capabilityb.Both Motor braking capability & Regenerative braking capabilityc.Motoring capabilityd.

118.

Slip power recovery system has nearly the characteristics ofDC shunt motora.

DC series motorb.Self excited dc motorc.Separately excited dc motord.

119.

Following is the ratio of air gap power Pg : rotor copper loss Pcu : mechanical power Pm1: (1-s): sa.1: s : (1-s)b.Pg =(1-S)Pmc.

Pg =S Pmd.

120.

Identify the current Id equation of Scherbius Drive system from the followinga.b.c.d.

121.


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For safe commutation slip S=________(m/n) cosa.-(m/n) cosb.-(n/m) cosc.(m/n) sind.

122.

In Slip power recovery the amount of power to be injected in rotor is _______(1-S)Pga.

S Pgb.

(1-S)Pmc.

S Pmd.

123.

Maximum .firing angle restricted for safe commutation of thyristors in Scherbius drive is

150a.165b.180c.

0d.

124.

Slip power recovery scheme among the following is________static rotor resistance controla.static Kramer s driveb.Four quadrant controlc.Regenerative controld.

125.

Expression for Rectifier output in Static Scherbius drive is ____________a.b.

c.d.

126.

Expression for Inverter input in Static Scherbius drive is ____________a.

b.c.d.

127.

In Scherbius Drive system in Vd1 equation n is called ____________Stator to rotor turns ration of motora.turns ratio of transformerb.Turns ratio of converterc.Slip of the motord.

128.

Following is the very low power factor drive

static rotor resistance controla.static Scherbius Driveb.Four quadrant controlc.Regenerative controld.

129.

Expression for Rectifier output in Static Scherbius drive is ____________a.b.c.d.

130.

Expression for Inverter input in Static Scherbius drive is ____________a.b.c.d.

131.

In Scherbius Drive system in Vd1 equation n is called ____________Stator to rotor turns ration of motora.turns ratio of transformerb.Turns ratio of converterc.Slip of the motord.

132.

Following is the very low power factor drivestatic rotor resistance controla.static Scherbius Driveb.Four quadrant controlc.Regenerative controld.

133.

The selection of control gear for a particular application is based on the consideration ofdutya.

134.


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starting torqueb.limitations on starting currentc.duty, starting torque & limitations on starting currentd.

Pole changing method of speed control is used inSlipring induction motora.Dc shunt motorb.Dc series motorc.squirrel cage induction motord.

135.

Which of the following is preferred for automatic drives

synchronous motorsa.ward Leonard controlled dc motorb.squirrel cage induction motorc.

-d.

136.

Belted wound rotor induction motor are preferred formachine toolsa.gyratory crushersb.belt converterc.water pumpsd.

137.

Belted wound rotor induction motor are preferred formachine toolsa.gyratory crushersb.

belt converterc.water pumpsd.

138.

The motor normally used for crane travel isAC slipring motora.

Ward Leonard controlled DC shunt motorb.Synchronousc.DC differentially compound motord.

139.

A wound rotor induction motor is preferred over squirrel cage induction motor when the majorconsideration involved is

high starting torquea.low starting currentb.speed control over limited rangec.high starting torque,low starting current,speed control over limited ranged.

140.

Stator voltage control for speed control of induction motors is suitable forfan and pump drivesa.

drive of a craneb. running if as generatorc.constant load drived.

141.

As compared to squirrel cage induction motor a wound motor induction motor is preferred when themajor consideration is

High starting torquea.low winding lossesb.slow speed operationc.High starting torque, low winding losses & slow speed operationd.

142.

In motor circuit static frequency changers are used forpower factor improvementa.improved coolingb.Reversal of directionc.speed regulationd.

143.

To save the energy during brakingDynamic braking is useda.Plugging is usedb.Regenerative braking is usedc.mechanical braking is usedd.

144.

In jaw crushers, a motor has to often started againstlow loada.medium loadb.normal loadc.heavy loadd.

145.

Centrifugal pumps are usually drive byd.c. shunt motora.d.c. series motorb.

146.


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squirrel cage I.M.c.-d.

Most commonly used AC motor isSynchronous motora.slip ring induction motorb.squirrel cage induction motorc.AC commutator induction motord.

147.

Belted slip ring I.M. is almost invariably used forcentrifugal blowersa.

jaw crushersb.water pumpc.screw pumpsd.

148.

The motor commonly used in computers and digital systems isDC shunt motora.Induction motorb.Stepper motorc.Synchronous motord.

149.

Which of the following drive can be used for derricks and winches?DC motors with Ward Leonard controla.AC slip-ring motorsb.Pole changing slipring motorsc.

DC Seperately excited motorsd.

150.

A pole changing type squirrel cage motor used in derricks has four, eight and twenty, fourPoles. In thisthe lowest speed is used for

liftinga.

hoistingb.loweringc.landing the loadd.

151.

Which of the following motor is preferred for blowerswound rotor I.Ma.Squirrel cage induction motorb.d.c. shunt motorc.d.c. series motord.

152.

Which of the following motor is preferred for synthetic fiber mills?

series motora.reluctance motorb.

shunt motorc. synchronous motord.

153.

Which of the following motor is preferred for synthetic fiber mills?series motora.reluctance motorb.shunt motorc.synchronous motord.

154.

The advantage of a synchronous motor in addition to its constant speed ishigh power factora.better efficiencyb.lower costc.high power factor, better efficiency & lower costd.

155.

Damper winding not used for___________speed controla.damping of oscillationsb.starting of synchronous motorc.high power factord.

156.

Most Synchronous motors are rated between150 KW to 15MWa.15MW to 150MWb.15 KW to 150 KWc.1 KW to 2 KWd.

157.

In Salient Pole motor '&delta' is the angle betweenV and Isa.

V and Eb.E and Isdc.Isd and Isqd.

158.


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In Cylindrical rotor wound motor for Motoring operation is Positivea.E lags Vb. is Positive and E lags Vc. is Positive or E lags Vd.

159.

A synchronous motor is found to be more economical when the load is above1 kWa.10 kWb.20 kWc.100 kWd.

160.

Expression for Salient pole rotor synchronous motor consists of ___ no. of parts1a.

2b.3c.4d.

161.

The time period of Reluctance torque component is_____ times of Synchronous torque1a.2b.3c.4d.

162.

The time period of Reluctance torque component is_____ times of Synchronous torque

1a.2b.

3c. 4d.

163.

In Cylindrical rotor wound field motor load angle is ____ for maximum torque

0a.90b.180c.165d.

164.

In Cylindrical rotor wound field motor load angle is ____ for maximum torque

0a.90b.

180c.165d.

165.

One of the following power circuits is used for synchronous motor speed control through Frequency

identifyV.S.Ia.A.C Voltage controllerb.3 controlled converterc.

-d.

166.

Multi motor control system is possible fromopen loopa.closed loopb.open or closed loopc.-d.

167.

Identify Self Control from the followingClosed loop controla.open loop controlb.

either closed or open loopc.

-d.

168.

Following is the scalar control mode of control in an synchronous motoropen loopa.closed loopb.open or closed loopc.-d.

169.

Identify variable frequency control mode from the followingseparate controla.self controlb.either a orc.-d.

170.

Multi motor control system is possible from171.


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true synchronous modea.closed loop modeb.open or closed loopc.-d.

Variable frequency control is possible in Synchronous motorbelow base frequencya.above base frequencyb.at base frequencyc.at any frequencyd.

172.

In Cylindrical rotor wound field motor for lagging power factorV leads Isa.V lags Isb.

E lags Vc.V lags Ed.

173.

In Salient pole wound field motor , reluctance torque is proportional to____Sin a.Sin 2b.Sin /2c.sin&phid.

174.

In Cylindrical rotor wound field motor for lagging power factorV leads Isa.

V lags Isb.E lags Vc.

V lags Ed.

175.

In Salient pole wound field motor , reluctance torque is proportional to____

Sin a.Sin 2b.Sin /2c.sin&phid.

176.

Frequency = 50 Hz, Poles = 4, Synchronous Speed for 3 - phase induction motor is1500 rpma.1000 rpmb.2000 rpmc.1200 rpmd.

177.

CSI fed Synchronous motor is suitable for-multi drivea.

unsuitable for multi driveb. suitable for both a & bc.-d.

178.

Identify the Constant Power Regionzero to base speeda.Above base speedb.slip speedc.-d.

179.

In True Synchronous mode Frequency is controlled fromEncodera.Oscillatorb.Inverterc.-d.

180.

PWM technique in Inverters for control of Synchronous motor is used forharmonic reductiona.higher output frequencyb.improving efficiencyc.reducing switching lossesd.

181.

The variable frequency supply to an induction motor for speed control can be made available usingVSIa.CSIb.cycle converterc.VSI, CSI & Cycle converterd.

182.

What is meant by VSI ?

source contain negligible impedancea.source contain more impedanceb.It is a variable voltage sourcec.

183.


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source impedance is zerod.

What is meant by CSI ?source contain large impedancea.source contain loss impedanceb.constant voltage sourcec.source impedance is zerod.

184.

In variable frequency control of synchronous motor drive the machine settles at new speedbefore damping oscillationsa.after damping oscillationsb.

beyond the rated frequencyc.at constant power regiond.

185.

How many Thyristors are required to construct a load commutated inverter for Synchronous motorDrive

3a.6b.12c.24d.

186.

In variable frequency control of synchronous motor drive the machine settles at new speedbefore damping oscillationsa.after damping oscillationsb.beyond the rated frequencyc.

at constant power regiond.

187.

How many Thyristors are required to construct a load commutated inverter for Synchronous motorDrive

3a.

6b.12c.24d.

188.

In load commutated Inverter fed Synchronous motor Commutation lead angle=180- l, totake care of commutation over lapa.take care of commutation failureb.take care of triggering of thyristorsc.take care of short circuit occurrencesd.

189.

In load commutated Inverter fed Synchronous motor, relation between phase current Is and DC link

current Ida.

b.c.d.

190.

In load commutated Inverter fed Synchronous motor there will ____ no. of converter sets3a.6b.2c.24d.

191.

In load commutated Inverter fed Synchronous motor , motoring operation takes place whenfirst set as inverter, second set as invertera.first set as rectifier ,second set as inverterb.first set as inverter second set as rectifierc.at constant power regiond.

192.

In load commutated Inverter fed Synchronous motor , regenerative braking operation takes placewhen

first set as inverter, second set as invertera.first set as rectifier ,second set as inverterb.first set as inverter second set as rectifierc.at constant power regiond.

193.

In load commutated Inverter fed Synchronous motor, commutation lead angle is equal to90- la.

180-lb.

90+ lc.

180 + ld.

194.

In load commutated Inverter fed Synchronous motor, leading power factor operation is possible byadjusting frequencya.

195.


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adjusting excitationb.adjusting speedc.adjusting torqued.

In load commutated CSI fed Synchronous motor, source voltage is______in series with a large value of inductora.in series with a large value of capacitorb.in series with a small value of inductorc.in parallel with a large value of inductord.

196.

In Closed loop control of load commutated CSI fed Synchronous motor, four quadrant operation with

regenerative braking is adoptablebelow 100MWa.beyond 100MWb.

equal to 100MWc.above 1000MWd.

197.

For high speed and high power drives ________ motors are usedCSI fed Synchronous motora.VSI fed Synchronous motorb.Cyclo converter fed Synchronous motorc.CSI fed Induction motord.

198.

Cyclo converter fed Synchronous motors are permissible for______________high speed, high frequencya.

low speed, low frequencyb.high speed, low frequencyc.

low speed , high frequencyd.

199.

For Cyclo converter fed Synchronous motors, operation is possible in____ no. of quadrants

3a.1b.2c.4d.

200.

A VSI feeding a Synchronous motor can be____________Separately controlled Synchronous motora.Self controlled Synchronous motorb.either a or bc.-d.

201.

In High rating blowers ____________ motors are usedVSI fed Synchronous motora.

CSI fed Synchronous motorb. Cyclo converter fed Synchronous motorc.CSI fed Induction motord.

202.

In High rating Conveyers ____________ motors are usedCSI fed Synchronous motora.VSI fed Synchronous motorb.Cyclo converter fed Synchronous motorc.CSI fed Induction motord.

203.

In main line traction______________ motors are usedCyclo converter fed Synchronous motora.VSI fed Synchronous motorb.CSI fed Synchronous motorc.CSI fed Induction motord.

204.

In Cyclo converter fed Synchronous motor, the out put frequency is limited to____ of input frequency1/3a.1/ 6b.1/ 2c.up to input frequencyd.

205.

In load commutated Cyclo converter fed Synchronous motors, line power factor _____is unitya.is poorb.is leadingc.is zerod.

206.

For stepdown Cyclo converter fed Synchronous motors, thyristors are commutated by_____

line commutationa.forced commutationb.voltage commutationc.

207.


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resonant commutationd.

For low speed and low frequency,higher power rating machines are preferred _____type of motorCyclo converter fed Synchronous motora.VSI fed Synchronous motorb.CSI fed Synchronous motorc.CSI fed Induction motod.

208.

For low speed and low frequency,higher power rating machines are preferred _____type of motorCyclo converter fed Synchronous motora.VSI fed Synchronous motorb.

CSI fed Synchronous motorc.CSI fed Induction motod.

209.


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JNTU ONLINE EXAMINATIONS [Mid 2 - EDS]

In a 3-phase, 10MVA, 11KV generator having 12% subtransient reactance, a 3-phase short-circuitoccurs at its terminals, the fault current will be

9090Aa.5250Ab.3030Ac.2650Ad.

1.

Which portion of the power system is least prone to faults?Alternatorsa.Switchgearb.Transformersc.

Overhead linesd.

2.

The magnitude of fault current depends upontotal impedance upto faulta.voltage at the fault pointb.

load current being supplied before occurrence of faultc.both total impedance upto fault and voltage at the fault pointd.

3.

A short-circuit current is identified byheavy current flowa.voltage riseb.voltage dropc.

light current flowd.

4.

Short-circuit currents are due tosingle phase to earth faulta.

phase to phase faultb.all the three phases to earth faultc.all the three phases short-circuitedd.

5.

The most serious consequence of a major uncleared short-circuit fault could beblowing of fusea.fireb.heavy voltage dropc.light voltage dropd.

6.

Which of the following results in symmetrical fault?Single phase to eartha.

Phase to phaseb.All the three phases to earthc.Two phases to earthd.

7.

Which portion of the transmission system is more prone to faults?Alternatora.Transformerb.Overhead linesc.Underground cabled.

8.

In a star-connencted system without neutral grounding, zero sequence currents arezeroa.vector sum of phase currentsb.same as rms value of phase currentsc.same as peak value of phase currentsd.

9.

In case of an unbalanced star-connected load supplied from an unbalanced 3-phase, 3-wire system,load currents will consist of

positive sequence componentsa.

negative sequence componentsb.zero sequence componentsc.positive sequence components and negative sequence componentsd.

10.

Series reactors are used toimprove the transmission efficiencya.improve the power factor of the power systemb.improve the voltage regulationc.bring down the fault level within the capacity of the switchgeard.

11.

The per unit impedance of a circuit element is 0.15. If the base KV and base MVA are halved, then thenew value of the per unit impedance of the circuit element will be

12.


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0.075a.0.15b.0.30c.0.60d.

A balance 3-phase system consists ofzero sequence currents onlya.positive sequence currents onlyb.negative and zero sequence currentsc.zero, negative and positive sequence currentsd.

13.

Series reactors are installed at strategic locations in a power system so as todischarge the capacitorsa.pass neutralizing surges of opposite natureb.

directly pass the fault surges to the groundc.not related to recatorsd.

14.

A power system network with a capacity of 100MVA has a source impedance of 10% at a point. Thefault level at that point is

10MVAa.30MVAb.300MVAc.1000MVAd.

15.

Zero sequence component in 3 phases voltage of delta is

line voltagea.zerob.

line voltage3c. line voltage/3d.

16.

The arcing contacts for a circuit are made ofcopper tungsten alloya.stainless steelb.hard pressed carbonc.aluminium alloyd.

17.

Minimum arcing voltage will be the least in case ofcarbona.copperb.silverc.tungstend.

18.

Circuit breakers usually operate under

steady-state short-circuit currenta. sub-transient state of short-circuit currentb.transient state of short-circuit currentc.square of the currentd.

19.

On occurrence of fault on the connected circuit, a circuit breaker operatesmanuallya.automaticallyb.manually through a control switchc.depending upon the circuit breaker designd.

20.

Current limiting reactors may beair-cored air cooleda.oil immersed magnetically shieldedb.oil immersed non-magnetically shieldedc.both air-cored air cooled and oil immersed magnetically shieldedd.

21.

The least expensive protection for over-current in low voltage system isrewirablea.upto 22kvb.upto 33kvc.above 33kvd.

22.

A circuit breaker is essentiallyan are extinguishera.a current interrupting deviceb.a power factor correcting devicec.a device for neutralizing the effects of transientsd.

23.

The recovery voltage will be maximum for power factor ofzeroa.0.5b.

24.


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0.707c.unityd.

In a circuit breaker the current that exists at the instant of contact separation is called therestriking currenta.breaking currentb.arc currentc.recovery currentd.

25.

The resistance of an electric arc can be increased byincreasing the concentration of ionized particlesa.

reducing the arc lengthb.splitting the arcc.increasing the arc x-sectiond.

26.

In a circuit breaker, the active recovery voltage depends uponcircuit conditionsa.power factorb.armature reactionc.voltaged.

27.

The rate of rise of restriking voltage (RRRV) depends uponsystem voltagea.circuit pf onlyb.switching condition onlyc.

both system voltage and circuit pf onlyd.

28.

Which of the following contact point metals has the highest melting point?Tungstena.Silverb.

Copperc.Aluminiumd.

29.

With the increase in mechanical force applied, the contact resistanceremains unaltereda.increasesb.decreasesc.unpredictabled.

30.

Sparking occurs on switching-off the load due to circuit highresistancea.

capacitanceb.inductancec.

skin effectd.

31.

Compared to the breaking capacity of circuit breaker its making capacity should normally bemorea.equalb.lessc.the two are unrelated to each otherd.

32.

Fault diverters are basicallycircuit breakersa.fast switchesb.fusesc.relaysd.

33.

The trip coil of a circuit breaker is connected through a CT of ratio 50:1.If the normal line current is160 A and circuit breaker is to operate at 125% normal line current, the trip mechanism should be setto operate at trip current of

3.2Aa.4Ab.5Ac.15Ad.

34.

Breaking capacity of circuit breakers is usually expressed inMVAa.MWb.Kilo-amperesc.KVd.

35.

The rating of a circuit breaker is usually determined on the basis of

symmetrical fault currenta.line to line fault currentb.single line to ground fault currentc.

36.


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double line to ground fault currentd.

Air blast circuit breakers employed for 400kv power system are designed to operate in0.1sa.50msb.10msc.200 sd.

37.

The pressure of air used in air blast circuit breaker is around

1kg/cm2

a.

10kg/cm2

b.

20kg/cm2c.

100kg/cm2d.

38.

The zero sequence impedance of different elements of power system isequala.not equalb.differentc.more than oned.

39.

The primary function of a fuse is toopen the circuita.protect the applianceb.protect the linec.

prevent excessive currents from flow through the circuitd.

40.

Operation of fuse is based uponphoto-electric effecta.heating effect of electric currentb.

magnetic effect of electric currentc.on voltage of the circuitd.

41.

The fuse blows off byarcinga.burningb.meltingc.absorbingd.

42.

An isolator is installedto isolate one portion of the circuit from anothera.

usually on both sides of a circuit breakerb.as a substitute for a circuit breakerc.

both to isolate one portion of the circuit from another and usually on both sides of a circuitbreakerd.

43.

A fuse is normally apower limiting devicea.voltage limiting deviceb.current limiting devicec.power factor correcting deviced.

44.

Fuses have got advantages ofcheapest type of protectiona.inverse time-current characteristicb.no maintenancec.Cheaper, inverse time current characteristic and no maintanced.

45.

A fuse isalways connected in series with the circuita.always connected in parallel with the circuitb.normally connected in series with the circuitc.normally connected in parallel with the circuitd.

46.

A fuse isnormally inserted in phase wirea.normally inserted in neutral wireb.never inserted in neutral wirec.never inserted in phase wired.

47.

The material used in liquid fuses isSF6a.

distilled waterb.carbon tetra chloridec.transformer oild.

48.


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Which of the following materials is more susceptible to oxidation?Silvera.Copperb.Tin and lead alloyc.irond.

49.

Re wirable fuse hasinverse time current characteristica.linear time-current characteristicb.square law time-current characteristicc.non linear time current chrematisticsd.

50.

Protection by fuses is generally not used beyond200Aa.

50Ab.25Ac.10Ad.

51.

A fuse in a motor circuit provides protection againstshort-circuita.over-loadb.open circuitc.short-circuit and overloadd.

52.

Operating time for fuse wire is about

0.1 msa.2msb.

0.1sc. few secondsd.

53.

The material used for fuse wire should be oflow resistivity and high melting pointa.high resistivity and high melting pointb.high resistivity and low melting pointc.low resistivity and low melting pointd.

54.

A material best suited for manufacturing of fuse wire issilvera.copperb.aluminiumc.zincd.

55.

Over-current protection respond to

increase in current above pick-up valuea. single line to earth faultsb.double line to earth faultsc.line to line to faultd.

56.

A relay used on short transmission lines ismho relaya.reactance relayb.impedance relayc.admittance relayd.

57.

HRC fuses provide best protection againstover loada.short-circuitsb.open circuitsc.reverse currentd.

58.

The rating of fuse is expressed in terms ofamperesa.voltsb.VARc.kvad.

59.

The delay fuses are used for protection oflight circuitsa.motorsb.fluorescent lampc.transformersd.

60.

In comparison to rewirable fuses HRC fuses have the advantages ofhigh speed operationa.high rupturing capacityb.

61.


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no ageing effectc.high reliabled.

HRC fuses provide best protection againstshort-circuita.lightningb.sparkingc.fired.

62.

A lightning arrester connected between the line and earth in a power systemprotects the terminal equipment against traveling surgesa.

protects the terminal equipment against direct lightning strokeb.suppresses high frequency oscillations in the linec.reflects back the traveling waves approaching itd.

63.

Basically a lightning arrester is asurge absorbera.surge diverterb.surge reflectorc.light emmiterd.

64.

A lightning arrester provideslow impedance patha.high impedance pathb.low resistance pathc.

high resistance path between line and earth during operationd.

65.

The most commonly used method for the protection of 3-phase feeder istime graded protectiona.differential protectionb.

reverse power protectionc.scalar protectiond.

66.

Earth wires are made ofcoppera.aluminiumb.ironc.galvanized stranded steeld.

67.

For an open-circuited transmission line, the reflection coefficient is1a.

-1b.zeroc.

0.7d.

68.

For a short-circuited transmission line, the reflection coefficient is1a.-1b.zeroc.0.5d.

69.

High current flow in transmission system causesIncreased power lossesa.decreased power lossesb.not effect on power lossesc.power losses constantd.

70.

Shunt compensation normally done inshort transmission systema.distribution systemb.long transmission systemc.medium transmission systemd.

71.

Series compensation normally done inA.C distribution systema.D.C distribution systemb.long transmission systemc.short transmission systemd.

72.

Neutral earthing is provided forthe safety of personnel from electric shocka.the safety of equipment and personnel against lightning and voltage surgesb.

reducing the voltage stress on lines and equipment with respect to earth under various operating andfault conditions

c.

controlling the earth f

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