Solution
Solution
4602CJA101001250012 JA
PART-A-PHYSICS
SECTION-I(i)
1) A block of mass m is attached with a massless spring of force constant k. The block is placed over
a rough inclined surface for which the coefficient of friction is , then minimum value of
M required to move the block up the plane is : (Neglect mass of string and pulley and friction in
pulley)
(A)
m
(B)
m
(C) 2m
(D)
m
2) P. E. of particle moving along x-axis is given as U = 2x3 + 3x2 – 12x + 6. At what position, particle
is in stable equilibrium :
(A) x = – 1
(B) x = +1
(C) x = – 2
(D) x = +2
3) A uniform chain is placed over a table such that part of it overhangs as shown. If chain
remains in equlibrium, then coefficient of static friction between chain and table will satisfy
following condition :-
(A) µ ≥ 1
(B) µ ≥ 0.75
(C) µ ≥ 0.5
(D) µ ≥ 0.3
4) In the shown system, pulleys and string are massless. One end of the string is pulled by the force
(A) g/2
(B) g
(C) 2g
(D) 0
5) A car starts from rest with an acceleration of which decreases linearly with time to zero in
10 second; after which the car continues at a constant speed. Determine the time required for the
car to travel 400 m from the start.
(A) 15.2 s
(B) 11.67 s
(C) 16.67 s
(D) 26.67 s
6) A projectile is given an initial velocity of , where is along the ground & is along the
2
vertical. If g = 10 m/s , the equation of its trajectory is :-
(A) y = 2x – 5x2
(B) 2y = 3x – 5x2
(C) 4y = 6x – 5x2
(D) 4y = 3x – 5x2
SECTION-I(ii)
1) A boy in the elevator with open roof shoots a bullet in vertical upward direction from a height of
1.5 above the floor of the elevator. The initial speed of the bullet with respect to elevator is 15 m/s.
The bullet strikes the floor after 2 seconds. Then (Assuming g = 10 m/s2)
(A) the relative velocity between the two stones remain constant till one hits the ground.
(B) both will have the same kinetic energy when they hit the ground.
(C) the time interval between their hitting the ground is 2 seconds.
(D) none of these
3) Two particles are projected simultaneously as shown in figure. If collision take place between the
(A)
(B)
(C)
(D)
5) The angle between two vectors is θ and the magnitude of is half of magnitude of . If
& then choose the correct statements :-
(A)
if c = then θ will be 90°
(B)
if c = then θ will be 60°
(C)
if c = then θ will be 45°
(D)
if c = then θ will be 180°
6) Two fixed frictionless inclined planes are shown in the figure. Two blocks A and B are placed on
SECTION-III
1) In the given figure a wedge of mass M is kept on a horizontal smooth surface. Two blocks of equal
mass m are arranged as shown in figure. All surfaces are smooth. Find the value of acceleration a (in
m/s2), so that blocks A and B do not slip over the wedge. (g = 10 m/s2)
2) Two blocks of mass 2 kg and 4 kg are connected through a massless inextensible string.
Coefficient of friction between 2 kg block and ground is 0.4 and between 4 kg block and ground is
0.6. Two forces F1 = 10 N and F2 = 20 N are applied on the block as shown in figure. Friction force
3) A mass m is supported as shown in the figure by ideal strings connected to a rigid wall and to a
mass 3m at rest on a fixed horizontal surface. The string connected to larger mass is horizontal, that
connected to smaller mass is vertical and the one connected to wall makes an angle 60° with
horizontal. Then the minimum coefficient so static friction between the larger mass and the
horizontal surface that permits the system to remain in equilibrium in the situation shown is .
Find n.
4) A mass m is attached to two spring having spring constant k is in equilibrium as shown in the
figure. The work done to slowly lift the block upward at constant speed by a distance mg/4k, is
. Find n?
5) A ring of mass m slides on a smooth vertical rod. A light string is attached to the ring and is
passing over a smooth peg distant a from the rod, and at the other end of the string is a mass
M(>m). The ring is held on a level with the peg and released. The distance that the ring moves
PART-B-CHEMISTRY
SECTION-I(i)
1) According to VBT, which of the following overlapping can result in π-type covalent bond in O2
molecule formation, when Z-axis is internuclear axis ?
(I) 2s – 2s (II) 2px – 2px (III) 1s – 1s (IV) 2py – 2py (V) 2pz – 2pz
(A) I, III
(B) II, V
(C) II, IV
(D) IV, V
3) The hydrated salt Na2SO4.nH2O, undergoes 55% loss in weight on heating and becomes
anhydrous. The approximate value of n will be :
(A) 5
(B) 3
(C) 7
(D) 10
4) Difference in wavelength of two extreme lines of H-atom in Balmer region is (Where RH is Rydberg
constant) :-
(A) 7.2 / RH
(B) 0.25 / RH
(C) 3.2 / RH
(D) 4 /RH
5) Magnetic moment of Xn+ (Z = 26) is B.M. Hence number of unpaired electrons and value of n
respectively are -
(A) 4, 2
(B) 2, 4
(C) 3, 1
(D) 0, 2
6) 5.6 gm CaO react with 4.48 litre of CO2 at STP & form CaCO3. Calculate mass of CaCO3.
(A) 10 gm
(B) 20 gm
(C) 30 gm
(D) 40 gm
SECTION-I(ii)
1)
(A)
(B)
(C)
(D)
(A) C2
(B) N2
(C) O2
(D) S2
5)
(A)
(B)
(C)
(D)
SECTION-III
1) 16 g of SOx gas occupies 5.6L at 1 atm and 273K. What will be the value of x ?
2)
A 50 watt bulb emits monochromatic red light of wavelength of 795 nm. The number of photons
emitted per second by the bulb is x × 1020. The value of x is _________.
3) Among the triatomic molecules/ions, BeCl2, N3–, N2O, NO2+, O3, SCl2, ICl2–, I3– and XeF2, the total
number of linear molecule(s)/ion(s) where the hybridization of the central atom does not have
contribution from the d–orbital(s) is
[Atomic number : S = 16, Cl = 17, I = 53 and Xe = 54]
4)
(i) BeO
(ii) BaO
(iii) Be(OH)2
(iv) Sr(OH)2
5) According to MO theory, number of species/ions from the following having identical bond order is
______.
CN–, NO+, O2, O2+, O22+.
PART-C-MATHEMATICS
SECTION-I(i)
(A) (–1, 3)
(B)
(C)
(D) (–1, 4)
(A) 1
(B) 2
(C) 3
(D) 4
3)
(A) 4
(B) 5
(C) 6
(D) 7
4) If the equation x2 –x–12 = 0 and kx2 + 10x + 3 = 0 may have one common root, then find the value
of k.
3 or
(A)
(B)
–3 or
3 or
(C)
(D)
–3 or
(A) 1
(B) 3
(C) 0
(D) infinite
6) The value of
(A)
(B)
(C)
(D) 1
SECTION-I(ii)
1) If the roots of the equation are equal in magnitude and opposite in sign, then
(A) p + q = r
(B) p + q = 2r
(C)
2) The solution(s) of the equation cos2x sin6x = cos3x sin5x in the interval [0, π] is/are
(A)
(B)
(C)
(D)
3) If 4cos2x – 8cosx + 3 0 for x ∈ [0,2π], then which of the following can be true
(A)
(B)
(C)
(D)
4) If terms then
(A)
(B) S16 = 2
(C) S33 = 3
(D)
(A) p = 3
(B) q = 2
(C) p = 9
(D) q = 4
6)
Let f(x) = ax2 + bx + c, (a ≠ 0) and f(x) = 0 has no real root. If (a + 3b + 9c) > 0, then
(A) a + b + c > 0
(B) a > 0, c > 0
(C) a > 0, c < 0
(D) 4a + 16b + 64c > 0
SECTION-III
1)
3) If three successive terms of a G.P. with common ratio r(r > 1) are the lengths of the sides of a
triangle and [r] denotes the greatest integer less than or equal to r, then 3[r] + [–r] is equal to :
4) Two roots of the cubic equation x3 – 5x2 – ax + 45 = 0 are real and additive inverse of each other
then ‘a’ is
PART-A-PHYSICS
SECTION-I(i)
Q. 1 2 3 4 5 6
A. A B C D C C
SECTION-I(ii)
Q. 7 8 9 10 11 12
A. B,D A,B,C A,C A,C,D A,B,D B,C
SECTION-III
Q. 13 14 15 16 17
A. 5 8 3 4 4
PART-B-CHEMISTRY
SECTION-I(i)
Q. 18 19 20 21 22 23
A. C A D C A A
SECTION-I(ii)
Q. 24 25 26 27 28 29
A. A,B,C,D A,B,D A,B A,B,D A,B,C,D A,B,C
SECTION-III
Q. 30 31 32 33 34
A. 2 2 4 2 3
PART-C-MATHEMATICS
SECTION-I(i)
Q. 35 36 37 38 39 40
A. C A C C A C
SECTION-I(ii)
Q. 41 42 43 44 45 46
A. B,C A,B,D A,B,C A,B,C,D C,D A,B,D
SECTION-III
Q. 47 48 49 50 51
A. 8 3 1 9 2
SOLUTIONS
PART-A-PHYSICS
1)
For mas m :
mg sin θ + fs, max = kx
mg sin θ + µmg cos θ = kx
for mass M :
Mgx =
at x = 1 (stable equilibrium)
3)
⇒µ ⇒µ=
4) a =0
5)
6)
vx = 2
vy = 3
x = 2t
y = 3t –
y=
2
4y = 6x – 5x
= = 4s
Since, relative velocity is Constant between them. So time interval between their hitting the
ground = 2 s.
⇒ (C) is correct
Option (D) is obvious from conservation of energy.
9)
aA = aB Þ aAB = 0
& θ = 45°
Time of collision
(A)
(B)
(C)
(D)
11) c2 = a2 + b2 – 2ab cos θ ........... (1)
a=b ........... (2)
∴ c2 = – a2 cos2 θ
Now check for A,B,C,D
12)
15)
At the instant 3m is about to slip, tension in all the strings are as shown
∴ 3 μmg = T cos 60° …(1)
and mg = T sin 60° …(2)
∴
16)
17)
Given a = 90 cm
M = 5 kg, m = 4 kg
By (i) mg y = Mgh
h= , h = ky, , {k = 0.8}
So, L = a2 + y2
2
.... (a)
h=y=L–a
h=L–a
h=L–a
L2 = (h + a)2 .... (b)
By (a) & (b)
a2 + y2 = h2 + 2ah + a2
y2 = k2y2 + 2aky
y2 =
y= =
y = 4m
PART-B-CHEMISTRY
18)
19)
20)
% loss in weight = 55
n = 9.67 ≈ 10
21)
= 3.2/RH
22)
24 = n(n + 2)
24 = n2 + 2n
n2 + 2n - 24 = 0
(n + 6) (n - 4) = 0
n = -6, n = 4
n = 4 (Since, the number of unpaired electrons cannot be negative)
So, to above 4 unpaired electrons the electronic configuration of 26 Xn+ must be 3d6, and the
oxidation number of
x=2
n=+2
Ans.-(A)
CaO is L.R.
1 mole CaO → 1 mole CaCO3
0.1 → 0.1 mole CaCO3
Mass = Mole × M. wt.
= 0.1 × 100 = 10 gm
24)
25)
For regular octahedral geometry there should be 6σ bonds and no l.p. on central atom
26)
C2 = 12 electron
All electron are paired.
27)
Spin multiplicity =
28)
29)
30)
M = 64
64 = 32 + 16x
x=2
31)
2 × 1020
= x × 1020
=2
32)
sp hybridisation
sp linear
sp2 Bent
sp3
linear sp3d
linear sp3d
linear
sp3d
33)
PART-C-MATHEMATICS
35)
36) Now,
= (logex)2
∴ The equations is
(logex)2 = logex – (logex)2 +1
2t2 – t – 1 = 0 [where, t = logex]
⇒ t = 1, –
Loge x = 1
⇒x=e
But ⇒
Then, log2(logex) is not defined.
∴ There is only ne real solution.
37)
2a =
a= ...(1)
=
38) Let α be a common root, then
α2 – α – 12 = 0, kα2 + 10α + 3 = 0.
∴
⇒ (12k + 3)2 = 117(10 + k)
⇒ (k – 3) (16k + 43) = 0
⇒ k = 3 or
39)
L.H.S ≤ 2. & R.H.S. ≥ 2
Hence L.H.S = 2 & R.H.S = 2
4x + 4-x = 2
Check x = 0 Possible hence only one solution.
40)
41)
Simplifying:
Roots are : α, –α
Product = pq – pr – qr
= pq – r (p + a)
x = nπ or
43)
4cos2x – 8cosx + 3 0
(2 cosx–3) (2 cosx –1) 0
⇒ 2cosx – 1 0 or 2 cosx – 3 < 0
44)
45)
P=9;q=4
46) ∵ a + 3b + 9c > 0
47)
1 – sin2x + sinx =
⇒ 9sin2x – 9sinx + 2 = 0
⇒
So, there are four principal solutions
in .
...(1)
2
r –r+1>0
always true
r2 + r – 1 > 0
…(2)
Taking intersection of (1) , (2)
As r > 1
[r] = 1 [–r] = –2
3[r] + [–r] = 1.
50)
α–α+β=5⇒β=5
125 – 125 – 5a + 45 = 0 ⇒ a = 9
51)
Let
⇒ x2(y – 1) – 4x(y – 1) + 1 = 0
Case I : y – 1 = 0
⇒ y = 1 (not possible)
Case II : y – 1 ≠ 0
D>0
16(y – 1)2 – 4(y – 1) > 0
(y – 1)(4y – 5) > 0