General Aptitude. Q.1 to Q.5 carry one mark each Q.1 Choose the most appropriate phrase form

182 Pages·2017·12.93 MB·English

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.General Aptitude.
Q.1 to Q.5 carry one mark each
Q.1 Choose the most appropriate phrase form the options given below to complete the following sentence.
The aircraft __________ take off as soon as its flight plan was filed.
(A) is allowed to (B) will be allowed to (C) was allowed to (D) has been allowed to
Ans. (C)
Q.2 Read the statements :
All women are entrepreneurs.
Some women are doctors.
Which of the following conclusions can be logically inferred from the above statements?
(A) All women are doctors (B) All doctors are entrepreneurs
(C) All entrepreneurs are women (D) Some entrepreneurs are doctors
Ans. (D)
Q.3 Choose the most appropriate word from the options given below to complete the following sentence.
Many ancient cultures attributed disease to supernatural causes. However, modern science has largely
helped ________ such notions.
(A) impel (B) dispel (C) propel (D) repel
Ans. (B)
Q.4 The statistics of runs scored in a series by four batsmen are provided in the following table. Who is the
most consistent batsman of these four?
Batsman Average Standard deviation
K 31.2 5.21
L 46.0 6.35
M 54.4 6.22
N 17.9 5.90
(A) K (B) L (C) M (D) N
Ans. (A)
Q.5 What is the next number in the series?
12 35 81 173 357 ____
Ans. 725
Sol.

So
Ans.
Hence, the correct answer is 725.
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Q.6 to Q.10 carry two marks each
Q.6 Find the odd one from the following group :
W,E,K,O I,Q,W,A F,N,T,X N,V,B,D
(A) W,E,K,O (B) I,Q,W,A (C) F,N,T,X (D) N,V,B,D
Ans. (D)
Sol. (A)

(B)

(C)

(D)

Hence, the correct option is (D).
Q.7 For submitting tax returns, all resident males with annual income below Rs. 10 lakh should fill up form
P and all resident females with income below Rs. 8 lakh should fill up form Q. All people with incomes
above Rs. 10 lakh should fill up form R, except non-residents with income above Rs. 15 lakhs, who
should fill up Form S. All others should fill form T. An example of a person who should fill form T is,
(A) A resident male with annual income Rs. 9 lakh
(B) A resident female with annual income Rs. 9 lakh
(C) A non-resident male with annual income Rs. 16 lakh
(D) A non-resident female with annual income Rs. 16 lakh
Ans. (B)
Sol. Resident female in between 8 to 10 lakh haven’t been mentioned.
Hence, the correct option is (B).
Q.8 A train that is 380 metres long, travelling at a uniform speed, crosses a platform in 60 seconds and
passes a man standing on the platform in 20 seconds. What is the length of the platform in metres?
Ans. 560
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Sol. Given :
Length of train 280m

Consider length of platform  Lm

So when a train passes a platform, then a train covers a length of its own and length of platform.
Distance covered by train when it crosses a platform(280L)m and it takes 60 sec. to cross it with
speed of S m/sec.
T
Now use DST
(280L)S 60 ….(i)
T
2nd case : When train passes a man then it covers a distance of its own length.
So now D 280m

With a speed of S m/sec, it takes 20 sec.
T
So now DST
 280S 20 ….(ii)
T
Solving equation (i) and (ii),
280L 60

280 20
 L2803280

 L560m

So length of platform is 560m. Ans.
Hence, the correct answer is 560.
Q.9 The exports and imports (in crores of Rs.) of a country from 2000 to 2007 are given in the following bar
chart. If the trade deficit is defined as excess of imports over exports, in which year is the trade deficit
1/5th of the exports?

(A) 2005 (B) 2004 (C) 2007 (D) 2006
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Ans. (D)
ImportExport 10 1
Sol. 2004,  
Export 70 7
9080 1  ImportExport 
In 2005,  Trade deficit 
 
80 8  Export 
20 1
In 2006, 
100 5
110100 1
In 2007, 
100 10
Hence, the correct option is (D).
Q.10 You are given three coins : one has heads on both faces, the second has tails on both faces, and the third
has a head on one face and a tail on the other. You choose a coin at random and toss it, and it comes up
heads. The probability that the other face is tails is
1 1 1 2
(A) (B) (C) (D)
4 3 2 3
Ans. (B)
Sol. We have three coins. In three coins, only the third coin we want as per condition given in question.

So no of ways to select a particular (third) coin from the three coins 3C
1
And now ways to select a single which we want 1C
1
Here favourable event  1C
1
And sample space  3C
1
So as we know :
Favourableevents
probability 
samplespace

1C 1
P 1  Ans.
3C 3
1
Hence, the correct option is (B).
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.Technical Part.
Q.1 to Q.25 carry one mark each
Q.1 For matrices of same dimension M, N and scalar c, which one of these properties DOES NOT
ALWAYS hold?
(A) (MT)T M (B) (cM)T c(M)T (C) (M N)T MT NT (D) MN = NM

Ans. (D)
Sol. Matrix multiplication is not commutative in general.
i.e. A B AB
xy yz xz
A B BA
xy yz
Hence, the correct option is (D).
Q.2 In a housing society, half of the families have a single child per family while the remaining half have
two children per family. The probability that a child picked at random, has a sibling is ___________.
Ans. 0.66
Sol. Let there are total N families, given that
 N  N N
Half, that means families have one child and also remaining have two children, i.e. 2
 
 2  2 2
 N   N  3N
Hence total children  2  
   
 2   2  2
It is noted that, sibling that mean brother and sister can occur in the family in which there are 2 children.
 N 
2
 
 2  2
Hence required probability   0.66
3N 3
2
Hence, the correct answer is 0.66.
 z2 z4j
Q.3 C is a closed path in the z-plane given by z 3. The value of the integral   dz is
c z2j 
(A) 4(1 j2) (B) 4(3 j2) (C) 4(3 j2) (D) 4(1 j2)
Ans. (C)
 z2 z4j
Sol. Given : f(z) 
 z2j 
Pole is at 2j
Let z  x jy
z  x2  y2 3 then z 3
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x2  y2 32, represents a circle with centre 0,0 and radius equal to 3.

Residue at 2j is z2j f z
 
z2j
  z2 z4j
z2j  46j
  z2j 
z2j
 f(z)dz 2j(Residueatz 2j)2j46j
C
Hence, the correct option is (C).
Q.4 A real (44)matrix A satisfies the equationA2 I, where I is the(44)identity matrix. The positive
eigen value of A is _______________.
Ans. 1
1 0 0 0
 
0 1 0 0
Sol. Let A 
0 0 1 0
 
0 0 0 1
Properties of eigen values
(1)     11114
1 2 3 4
[by the summation property of the eigen value]
(2)     1
1 2 3 4
[by the product property of the eigen value]
So, 1 satisfy these above equations.
Note : A2 I that means involutory matrix, for involuntary matrix only 1 is the eigen
value. So, the positive eigen value = 1.
Hence, the correct answer is 1.
Q.5 LetX , X andX be independent and identically distributed random variables with the uniform
1 2 3
distribution on 0,1. The probability P {X is the largest} is _______________.
1
Ans. 0.333
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Sol. Probability, P{X }P{X }P{X } …….(i)
1 2 3
As we know that the total probability = 1
Hence P{X }P{X }P{X }1
1 2 3
3P{X }1
1
1
P{X } 0.333
1 3
Hence, the correct answer is 0.333.
Q.6 For maximum power transfer between two cascaded sections of an electrical network, the relationship
between the output impedanceZ of the first section to the input impedanceZ of the second section is
1 2
(A) Z Z (B)Z Z (C) Z Z* (D) Z Z*
2 1 2 1 2 1 2 1
Ans. (C)
Sol. Two cascaded networks N and N are shown below.
1 2

If input impedance of N is Z and output impedance is Z .
i 0
Then equivalent circuit is :

Where V and V are input and output voltage.
i 0
Output impedance of 1st section is Z and input impedance of 2nd section is Z .
1 2

For power transfer from N to N .
1 2
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For maximum power transfer from N to N .
1 2
P :Z Z*
12(max) 2 1
Hence, the correct option is (C).
Q.7 Consider the configuration shown in the figure which is a portion of a larger electrical network

For R 1 and currents i 2A, i 1A, i 4A,which one of the following is TRUE?
1 4 5
(A) i 5A
6
(B) i 5A
3
(C) Data is sufficient to conclude that the supposed currents are impossible

(D) Data is insufficient to identify the currents i , i , and i
2 3 6
Ans. (A)
Sol.

Given :R1 and i 2 A, i 1A,
1 4
i 4 A
5
Applying KCL at node (1),
i i i
1 4 2
21i
2
i 1A
2
Applying KCL at node (2),
i i i
2 5 3
14i
3
i 3 A
3
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Applying KCL at node (3),
i i i
1 3 6
i i i
6 1 3
i 2(3)5 A
6
Hence, the correct option is (A)
Q.8 When the optical power incident on a photodiode is 10 W and the responsivity is 0.8A/W,the

photocurrent generated (in A) is ___________.
Ans. 8
Sol. Given :
Optical power incident P10 W
Responsivity 0.8 A/W
We know that,
I
Responsivity  P
P
I 0.8108 A
P
Hence, the correct answer is 8.
Q.9 In the figure, assume that the forward voltage drops of the PN diodeD and Schottky diodeD are 0.7 V
1 2
and 0.3 V, respectively. If ON denotes conducting state of the diode and OFF denotes non-conducting
state of the diode, then in the circuit,

(A) bothD andD are ON (B)D is ON and D is OFF
1 2 1 2
(C) bothD and D are OFF (D) D is OFF andD is ON
1 2 1 2
Q.10 If fixed positive charges are present in the gate oxide of an n-channel enhancement type MOSFET, it
will lead to
(A) a decrease in the threshold voltage. (B) channel length modulation.
(C) an increase in substrate leakage current. (D) an increase in accumulation capacitance.
Ans. (A)
Sol.
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When positive gate voltage is applied then electrons of p-type substrate are attracted and they form a
inversion layer.
If already positive charges are present on gate, then less voltage is required to induce n-channel.
Hence it will reduce the threshold voltage.
Hence, the correct option is (A).
Q.11 A good current buffer has
(A) low input impedance and low output impedance.
(B) low input impedance and high output impedance.
(C) high input impedance and low output impedance.
(D) high input impedance and high output impedance.
Ans. (B)
Sol. For a good current buffer or current amplifier circuit is shown below

For ideal current amplifier
I I
i s
Hence value of R should be zero
i
and I  I
L 0
Hence, value of R should be infinite.
0
Hence, the correct option is (B).
Q.12 In the ac equivalent circuit shown in the figure, if i is the input current and R is very large, the type
in F
of feedback is