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IIT JEE-2008 (PAPER-1)

C. Question paper format:

14. The question paper consists of 3 parts (Part-I : Mathematics, Part-II : Physics, Part-III : Chemistry).

Each part has 4 sections.

15. Section I contains 6 multiple choice questions. Each question has 4 choices (A), (B), (C) and (D), out

of which only one is correct.

16. Section II contains 4 multiple correct answer type question. Each question has 4 choices (A), (B), (C)

and (D), out of which one or more answers are correct.

17.Section III

contains 4 Reasoning type questions. Each question contains STATEMENT-1 andSTATEMENT-2.

Bubble (A) if both the statements are TRUE and STATEMENT-2 is the correct explanation of

STATEMENT-1.

Bubble (B) if both the statements are TRUE but STATEMENT-2 is NOT the correct explanation of

STATEMENT-1.

Bubble (C) if STATEMENT-1 is TRUE and STATEMENT-2 is FALSE

Bubble (D) if STATEMENT-1 is FALSE and STATEMENT-2 is TRUE

18. Section IV contains 3 sets of Linked-Comprehension type questions. Each set consists of a paragraph

followed by 3 questions. Each question has 4 choices (A), (B), (C) and (D), out of which only one is

correct.

D. Marking Scheme:

19. For each question in Section I, you will be awarded 3 marks if you have darkened only the bubble

corresponding to the correct answer and zero mark if no bubble is darkened. In all other cases, minus

one (1) mark will be awarded.

20. For each question in Section II, you will be awarded 4 marks if you have darkened all the bubble(s)

corresponding to the correct answer and zero mark for all other cases. It may be noted that there is no

negative marking for wrong answer.

21. For each question in Section III, you will be awarded 3 marks if you darken only the bubble



22. For each question in Section IV, you will be awarded 4 marks if you darken only the bubble



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IIT JEE-2008 PAPER-1

MATHEMATICS

PART-ISECTION - I

Straight Objective Type

This section contains 6 multiple choice questions. Each question has 4 choices (A), (B), (C) and (D), out

of which ONLY ONE is correct.

There is NEGATIVE marking. 1 mark will be deducted for wrong answer.

Q.1 The total number of local maxima and local minima of the function

f(x) =

2x1,x

1x3,)x2(3/2

3

is

(A) 0 (B) 1 (C) 2 (D) 3

Ans. [C]

Q.2 Let a andb be non-zero real numbers. Then, the equation

(ax2 + by2 + c) (x25xy + 6y2) = 0represents

(A) four straight lines, when c= 0 and a, b are of the same sign.

(B) two straight lines and a circle, when a= b, and c is of sign opposite to that ofa.

(C) two straight lines and a hyperbola, whenaandb are of the same sign and c is of sign opposite to that

of a

(D) a circle and an ellipse, when a andb are of the same sign and c is of sign opposite to that ofa.

Ans. [B]

Q.3 Let

g(x) =)1x(coslog

)1x(m

n

; 0 < x < 2, m and n are integers, m 0, n > 0 and letp be the left hand

derivative of | x 1 | at x = 1. If1x

Lim g(x) =p, then

(A) n = 1, m = 1 (B) n = 1, m = 1 (C) n = 2, m = 2 (D) n > 2, m = n

Ans. [C]

Q.4 If 0 < x < 1, then 2x1 [{x cos (cot1 x) + sin (cot1 x)}21]1/2 =

(A) 2x1

x

(B) x (C) x2

x1 (D)2

x1Ans. [C]

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Q.5 The edges of a parallelopiped are of unit length and are parallel to non-coplanar unit vectors c,b,a

such that2

1accbba . Then the volume of the parallelopiped is

(A)2

1(B)

22

1(C)

2

3(D)

3

1

Ans. [A]

Q.6 Consider the two curves

C1

: y2 = 4x

C2

: x2 + y26x + 1 = 0

Then,

(A) C1

and C2

touch each other only at one point

(B) C1

and C2

touch each other exactly at two points

(C) C1

and C2intersect (but do not touch) at exactly two points

(D) C1

and C2

neither intersect nor touch each other

Ans. [B]

SECTION - II

Multiple Correct Answers Type

This section contains 4 multiple correct answer(s) type questions. Each question has 4 choices (A), (B),

(C) and (D), out of which ONE OR MORE is/are correct.

There is NO NEGATIVE marking.

Q.7 Letf(x) be a non-constant twice differentiable function defined on (, ) such thatf(x) =f(1x) and

f '

4

1= 0. Then

(A) f ''(x) vanishes at least twice on [0, 1]

(B) f '

2

1= 0

(C)

2/1

2/1

dxxsin2

1xf = 0

(D) 2/1

0

tsindte)t(f =

1

2/1

tsindte)t1(f

Ans. [A,B,C,D]

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Q.8 Let Sn

=

n

1k22

kknn

nand T

n=

1n

0k22 kknn

n, for n = 1, 2, 3, ....... Then,

(A) Sn

33

(C) T

n

33

Ans. [A, D]

Q.9 A straight line through the vertex P of a triangle PQR intersects the side QR at the point S and the

circumcircle of the triangle PQR at the point T. If S is not the centre of the circumcircle, then

(A)PS

1+

ST

1

SRQS

2

(C)PS

1+

ST

1

QR

4

Ans. [B, D]

Q.10 Let P(x1, y

1) and Q(x

2, y

2), y

1< 0, y

2< 0, be the end points of the latus rectum of the ellipse

x2 + 4y2 = 4. The equations of parabolas with latus rectum PQ are

(A) x2 + 32 y = 3 + 3 (B) x2 32 y = 3 + 3

(C) x2 + 32 y = 3 3 (D) x2 32 y = 3 3

Ans. [B, C]

SECTION - III

Reasoning Type

This section contains 4 reasoning type questions. Each question has 4 choices (A), (B), (C) and (D), out



Q.11 Consider three planesP

1: x y + z = 1

P2

: x + y z = 1

P3

: x 3y + 3z = 2

Let L1, L

2, L

3be the lines of intersection of the planes P

2and P

3, P

3and P

1, and P

1and P

2, respectively.

STATEMENT-1 :At least two of the lines L1, L

2and L

3are non-parallel.

and

STATEMENT-2 : The three planes do not have a common point.

(A) STATEMENT-1 is True, STATEMENT-2 is True; STATEMENT-2 is a correct explanation for

STATEMENT-1

(B) STATEMENT-1 is True, STATEMENT-2 is True; STATEMENT-2 is NOT a correct explanation

for STATEMENT-1

(C) STATEMENT-1 is True, STATEMENT-2 is False

(D) STATEMENT-1 is False, STATEMENT-2 is True

Ans. [D]

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Q.12 Consider the system of equations

x 2y + 3z = 1

x + y 2z = k

x 3y + 4z = 1

STATEMENT-1 : The system of equations has no solution for k 3.and

STATEMENT-2 : The determinant

141

k21131

0, for k 3.

(A) STATEMENT-1 is True, STATEMENT-2 is True ; STATEMENT-2 is a correct explanation for

STATEMENT-1

(B) STATEMENT-1 is True, STATEMENT-2 is True ; STATEMENT-2 is NOT a correct explanation

for STATEMENT-1



Ans. [A]

Q.13 Letfandg be real valued functions defined on interval (1, 1) such that g''(x) is continuous, g(0) 0,

g'(0) = 0, g''(0) 0, and f (x) = g (x) sin x.STATEMENT-1 :

0xLim

[g(x) cot x g(0) cosec x] = f ''(0)

and

STATEMENT-2 : f '(0) = g(0)


STATEMENT-1

(B) STATEMENT-1 is True, STATEMENT-2 is True ; STATEMENT-2 is NOT a correct explanation

for STATEMENT-1



Ans. [B]

Q.14 Consider the system of equations

ax + by = 0, cx + dy = 0, where a, b, c, d {0, 1}.

STATEMENT-1 : The probability that the system of equations has a unique solution is2

3.

and

STATEMENT-2 : The probability that the system of equations has a solution is 1.


STATEMENT-1

(B) STATEMENT-1 is True, STATEMENT-2 is True ; STATEMENT-2 is NOT a correct explanationfor STATEMENT-1



Ans. [B]

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SECTION - IV

Linked Comprehension Type

This section contains 3 paragraphs. Based upon each paragraph, 3 multiple choice questions have to be

answered. Each question has 4 choices (A), (B), (C) and (D), out of which ONLY ONE is correct.


Paragraph for Question Nos. 15 to 17

A circle C of radius 1 is inscribed in an equilateral triangle PQR. The points of contact of C with the sidesPQ, QR, RP are D, E, F respectively. The line PQ is given by the equation 3 x + y6 = 0 and the

point D is

2

3,

2

33. Further, it is given that the origin and the centre of C are on the same side of the

line PQ.

Q.15 The equation of circle C is

(A) (x 32 )2 + (y 1)2 = 1 (B) (x 32 )

2 + (y +2

1)2 = 1

(C) (x 3 )2 + (y + 1)2 = 1 (D) (x 3 )

2 + (y 1)2 = 1

Ans. [D]

Q.16 Points E and F are given by

(A)

2

3,

2

3, 0,3 (B)

2

1,

2

3, 0,3

(C)

2

3,

2

3,

2

1,

2

3(D)

2

3,

2

3,

2

1,

2

3

Ans. [A]

Q.17 Equations of the sides QR, RP are

(A) y =3

2x + 1, y =

3

2x 1 (B) y =

3

1x, y = 0

(C) y =2

3x + 1, y =

2

3x 1 (D) y = 3 x, y = 0

Ans. [D]

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Consider the functions defined implicitly by the equation y33y + x = 0 on various intervals in the real

line.

If x (, 2) (2, ), the equation implicitly defines a unique real valued differentiable functiony =f(x).

If x (2, 2), the equation implicitly defines a unique real valued differentiable function y = g(x)satisfying g(0) = 0.

Q.18 If f(10 2 ) = 22 , then f '' (10 2 ) =

(A) 2337

24(B) 2337

24 (C)

37

243 (D) 37

243

Ans. [B]

Q.19 The area of the region bounded by the curve y =f(x), the x-axis, and the lines x = a and x = b,

where < a < b < 2, is

(A) b

a 1))x(f(3

x2 dx + bf(b) af(a) (B)

b

a 1))x(f(3

x2 dx + bf(b) af(a)

(C) b

a 1))x(f(3

x2 dx bf(b) + af(a) (D)

b

a 1))x(f(3

x2 dx bf(b) + af(a)

Ans. [A]

Q.20 dx)x('g

1

1

=

(A) 2g(1) (B) 0 (C) 2 g(1) (D) 2 g(1)

Ans. [D]


Let A, B, C be three sets of complex numbers as defined below

A = 1zIm:z

B = 3|2z|:z i

C = 2)z)1Re((:z iQ.21 The number of elements in the set A B C is

(A) 0 (B) 1 (C) 2 (D) Ans. [B]

Q.22 Let z be any point in A B C. Then, | z + 1 i |2 + | z 5 i |2 lies between(A) 25 and 29 (B) 30 and 34 (C) 35 and 39 (D) 40 and 44

Ans. [C]

Q.23 Letz be any point in A B C and let w be any point satisfying | w 2 i | < 3.Then, | z | | w | + 3 lies between

(A) 6 and 3 (B) 3 and 6 (C) 6 and 6 (D) 3 and 9

Ans. [D]

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PHYSICS

PART-IISECTION - I

Straight Objective Type

This section contains 6 multiple choice questions. Each question has 4 choices (A), (B), (C) and (D), out


Q.24 A spherically symmetric gravitational system of particles has a mass density

Rrfor0Rrfor0

where 0

is a constant. A test mass can undergo circular motion under the influence of the gravitational

field of particles. Its speed V as a function of distance r (0 < r < ) from the centre of the system isrepresented by :

(A)

R

V

r

(B)

R

V

r

(C)

R

V

r

(D)

R

V

r

Ans. [C]

Q.25 Two beams of red and violet colours are made to pass separately through a prism (angle of the prism is60). In the position of minimum deviation, the angle of refraction will be :

(A) 30 for both the colours (B) greater for the violet colour

(C) greater for the red colour (D) equal but not 30 for both the colours

Ans. [A]

Q.26 An ideal gas is expanding such that PT2 = constant. The coefficient of volume expansion of the gas is :

(A)T

1(B)

T

2(C)

T

3(D)

T

4

Ans. [C]

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Q.27 Figure shows three resistor configurations R1, R2 and R3 connected to 3V battery. If the power dissipated

by the configuration R1, R2 and R3 is P1, P2 and P3 respectively, then

Figure :

3V

1

1

1

1

1

R1

1

1

11

1

3V

R2

1

1

11

1

3V

R3

(A) P1 > P2 > P3 (B) P1 > P3 > P2 (C) P2 > P1 > P3 (D) P3 > P2 > P1

Ans. [C]

Q.28 Which one of the following statements is WRONG in the context of X-rays generated from a X-ray

tube ?

(A) Wavelength of characteristic X-rays decreases when the atomic number of the target increases

(B) Cut-off wavelength of the continuous X-rays depends on the atomic number of the target

(C) Intensity of the characteristic X-rays depends on the electrical power given to the X-rays tube

(D) Cut-off wavelength of the continuous X-rays depends on the energy of the electrons in the X-ray

tube

Ans. [B]

Q.29 Students I, II and III perform an experiment for measuring the acceleration due to gravity (g) using

pendulum. They use different lengths of the pendulum and/or record time for different number of oscillations.

The observations are shown in the table.

Least count for length = 0.1 cm

Least count for time = 0.1 s

StudentLength of the

Pendulum (cm)Number of

oscilltions (n)Total time for (n)

oscillations (s)Time

period (s)

I 64.0 8 128.0 16.0

II 64.0 4 64.0 16.0

III 20.0 4 36.0 9.0

If EI, E

IIand E

IIIare the percentage error in g, i.e.,

100

g

gfor students I, II and III, respectively,,

(A) EI = 0 (B) EI is minimum (C) EI = EII (D) EIIis maximumAns. [B]

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SECTION - II

Multiple Correct Answers Type

This section contains 4 multiple correct answer(s) type questions. Each question has 4 choices (A), (B),

(C) and (D), out of which ONE OR MORE is/are correct.

Q.30 In a Young's double slit experiment, the separation between the two slits is d and the wavelength of the

light is. The intensity of light falling on slit 1 is four times the intensity of light falling on slit 1. Choose thecorrect choice(s).

(A) If d = , the screen will contain only on maximum(B) If < d < 2, at least one more maximum (besides the central maximum) will be observed on thescreen

(C) If the intensity of light falling on slit 1 is reduced so that it becomes equal to that of slit 2, the intensities

of the observed dark and bright fringes will increase

(D) If the intensity of light falling on slit 2 is increased so that it becomes equal to that of slit 1, the

intensities of the observed dark and bright fringes will increase

Ans. [A, B]

Q.31 A particle of mass m and charge q, moving with velocity V enters Region II normal to the boundary as

shown in the figure. Region II has a uniform magnetic field B perpendicular to the plane of the paper. The

length of the Region II is . Choose the correct choice(s)

Figure

Region II Region IIIRegion I

V

(A) The particle enters Region III only if its velocity V >

m

Bq

(B) The particle enters Region III only if its velocity V

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