8/8/2019 IIT Study Circle Paper1
1/14
xa/2
a, d
4a2
yx2d
F F
f
f
MOCK TEST PAPER I
SOLUTION
1. (B) f F ma 0 = > W. D. = F x f x 0 <
2. (A) ( ) ( )y yB ATcos
a g a gm
= > =
( ) ( )B AB A
y h y
t t
= =
W X Z + ( )120 7.5 90 8 30 5 > +
W 2y ( )120 7.5 2 60 8.5 < energy released
X y Z + ( )90 8 60 83.5 30 5 > +
8/8/2019 IIT Study Circle Paper1
3/14
V
dqu
ql
V
d
10. (A), (C), (D)
( )
0 0
eq
0
A Ak 2 2C
d dk 1 A
2d
= +
+ =
0Aq k v2d = l
0u
Aq v
2d =
11. (A) (B), (C)
A
B
C
2
A
2
B
2
C
va i
R
va a i a j
Rv
a 2ai jR
= =
=
r$
r$ $
r$ $
12. (A), (B)
E.dl 0
g.dl 0
=
=
ur ur
r ur
13. (B)
( )F f r 0F f
= =
( )
Fsin f mgsin
mgsinF
1 sin
+ =
= +
8/8/2019 IIT Study Circle Paper1
4/14
airmedium
S1
S2D
O
14. (C) ( ) ( )F N mg F cos = /
1 mgsintan ; F1 sin3
= = + Q
15. (A)
( )
( )
mgsin Fsin f
F f mgsin
F1 sin
= + +
=
= + +
for, ( )minF , sin 1 + =
2 6 3
= =
16. (A)
Path difference = xd
D
at Pfor maxima.
medium
xdn
D=
( )0nD nD
xd d t
= = +
( )20
Speed of nth order maxima dx nDat t dt d t
= = +
17. (B) fringe width( )0
D Dd d t = =
+
18.( )0
1t
+
decreases with time
hence pattern gets narrower central maxima in always at 0.
8/8/2019 IIT Study Circle Paper1
5/14
C
AD
12
3 4
y
x
19. (A) (q)(B) (p)(C) (r)(D) (q)
As water flows out,
PC decrease as volume increase.
Dp also decrease.
2 2A A ctm A
A
1 h 1p v g p v O2 2 2p conct
+ + = + +
=
( )2 2B A A AB
1 h 1p 4v pg p v2 2 2p decrease
+ + = +
20. (A) (p),(q)(B) (p),(r)(C) (q),(s)
8/8/2019 IIT Study Circle Paper1
6/14
H OH
H OH
COOH
COOH
H OH
H OH
COOH
OH
H 3
C 4
C5CH
2CH =
1CH
CH3
(D) (q), (s)
1 2 3 4
1 2 3 4
1 2 3 4
y 0 y 0 y 0 y 0
v 0 v 0 v 0 v 0
a 0 a 0 a 0 a 0
< > > > >
21. (B) For ( )4Zn Hg NCS we have K sp = S2
7S 2.2 10 0.000469= =
22. (B) [ ]10
14
max
10Ag 10 M1
= =
12
10remaining
10Br 0.01M
10
= =
Hence 99% of Br have get removed23. (B) The p ka of CH 3COOH is 4.74 hence mixture
(B) is best so that the ratio of the buffer components will be 1 resulting into abuffer with a high buffer capacity
24. (C) 3-methyl-pent-1-en-4-yne
25. (C) C = C C C C C C C C C
1-deceneC C = C C C C C C C C 2-deceneC C C = C C C C C C C 3-deceneC C C C = C C C C C C 4-deceneC C C C C = C C C C C 5-decene
So 4 of these can show cis trans isomerism26. (B) it has to be the meso compound which is
Which can be drawn as
27. (C) This is because CH 3 shows +I effect.
28. (B) There is no loss of C on ozonolysis
8/8/2019 IIT Study Circle Paper1
7/14
29. (A), (B), (C) Factual question
30.
31. (B), (C) There is lp lp repulsion in F 2 so the bond strength is lesser than Cl 2 .
32. (D) Carbon has small size so form bonds readily
33. (C) 2 3 2 3Na CO 2HCl 2NaCl H CO+ +
34. (A)[ ]HIn
H InK
HIn
+ = , so that ratio depends on HInK and pH .
35. (C) HPh will not exhibit color change during this titration.
36. (C) Since it contains the metal-carbon bond.
37. (C) Protic solvent cannot be used
38. (D) aldehyde + RMgX gives after hydrolysis a secondary alcohol
39. (A) (q)(B) (s)(C) (r)(D) (p)These are as per the VSEPR theory
40. (A) - (s)(B) - (r) (q) (s)( C) (q) (s)(D) - (s)
Assuming Neglection of No in s option
MOCK TEST PAPER
SOLUTION I
41.(C) The domain of this function ( ) [ ]xf x log x
= is ( )1,
For 1 < x < 2, f(x) = 0 and for n x n 1 < + where n I + and n 2 , the function f(x) is decreasing. Therefore, the maximumvalue of f(x) is 1.A = 1
( )g x sinx cosx
1 sinx cosx 2
= + +
minimum value of g(x) = 1, B = 1
8/8/2019 IIT Study Circle Paper1
8/14
A = B
42.(A) Let ( ) ( )x 2 x 3f x e x and g x e x = =
( ) ( ) ( )x 2 x x
f ' x e 2x x e e .x x 2
= + =
0
1
0 2 +
2
So, f(x) has one solution.
( ) ( )x 2 3 x x 2g ' x e .3x x e e x x 3 = =
( )3
3g 3 1
e = >
0 3
0 3
+ +1
Therefore. g(x) has two solutions
43.(D) Let ( )1 1x , y be the foot of the r from focus upon the tangent.( )
( ) ( )
1 12 2
1 1
3 1 8x 1 y 11
3 1 3 1x , y 2, 2
+ + += = = + =
With respect to (2, 2), images of (7, 13) and (1, 1) will lie on the axis and thedirectrix of the parabola. The two points are (3, 17) and (5, 3)
slope of the axis1 17
81 3
+= = +
equation of the directrix is, ( )1y 3 x 58
+ = x 8y 19 0 + + =
44.(B)
2
2
2 1 dxx x x
I 1 11
xx
+ = + +
Let 1 11 txx
+ + =
2
dt 2I 2 c
t t= = +
2xc
x x 1= +
+ +
8/8/2019 IIT Study Circle Paper1
9/14
45.(D) For n 3 , 1 2 3 n 1na a a ...... a
an 1
+ + + +=
( ) n 1 2 n 1n 1 a a a ......... a = + + +
( )
1 2 nn 1
n n
nn
a a .......... aa
nn 1 a a
nna
an
++ + +=
+=
= =
n 1 n 9 3
1 2 23
2
a a a a 99
a a 19 aa 992 2a 179
+ = = =+ +
= ==
46.(B)
Total words =2 3 2 2 3
1 1 2 1 2
4! 4! 4! 4!C C C C C 4!
3! 2!2! 2! 4! + + + +
= 24 + 6 + 72 + 1 + 24 = 127
Probability that it has all letters distinct = 24
127.
47.(B) ( )( )3
2 22 2
1 1f g x x 3 x
x x = + +
( )( ) ( )3
g x 3g x= ( ) 3f x x 3x =
( ) 2f ' x 3x 3=
48.(A) Let the roots be k ,k,kr
r
31 a 1 1k r 1 , k k r 8 8 2 + + = = =
2
2
arr r 18
ar r 1 1 0
4
+ + =
+ + =
a a1 2 and 1 2
4 4
8/8/2019 IIT Study Circle Paper1
10/14
a 12, a 4
MORE THAN ONE CORRECT
49.(A),(B), (D) Let ( ) ( )( )g x 4 lnx lnx ..........= +
( )4, 1 x e
g x 5, x e
, x e
<
50.(B), (C) ( )f x 3sinx cosx 2 2sin x 26 = + = +
Since f(x) is one to one and onto, therefore f 1 exists.
( )( ) ( )1 1fof x x 2sin f x 2 x6
= + =
( )1 1 xf x sin 12 6
= +
x1 1
2 for all [ ]x 0,4
( )1 1
1
x 2f x cos
2 2 6
2 x 2cos3 2
= +
=
51.(A),(C) ( )( )
( ) ( )( )p x,y ,z
f x,y,zx y y z z x
= + + +
The polynomial ( )p x,y,z has degree 3and ( ) ( ) ( )p x,x,z p x,y,y p x,y,x 0= = = Thus p has factors x y, y z, z x upto a constant which turns out to be 1.
( )( ) ( )( )
( ) ( )( )
x y y z z xf x,y,z
x y y z z x
=+ + +
Since, x y x y < + y z y z < + z x z x < +
we get ( )f x,y,z 1< Using x y z, y z x, z x y < < <
we get ( ) z x yf x,y,zx y y z z x
< + + +
8/8/2019 IIT Study Circle Paper1
11/14
O
P (x , y )1 1
Q12
xy yz zx 1
x y y z z x 8=
The equation of the circle is x 2 + y2 = 10
1 1y 1, x 3= = ( ) ( )1 1P x ,y P 3,1=
OP 3i j= +uuur
Q lies on AP, A < Q < PQ (1, 1) or (2, 1) as abscises a is an integer
There are two values of OQuuur
OQ i j and 2i j= + +uuur
8/8/2019 IIT Study Circle Paper1
12/14
OP,OQ 3 1 4 and 6 1 7= + = + =uuur uuur
PQ OQ OP 2i j 3i j i
Also i j 3i j 2i
= = + = + =
uuur uuur uuur
Max and min of PQ 2=uuur
and 1 respectively.
PARAGRAPH II
Slope of tangent at P(x, y) =dy
Mdx
= Equation of tangent is y = mx mX + Y
The coordinate of Q Y YX ,2m 2
Y2tan
YX
2m
=
56.(B)If r rN and D are of same sign i.e., tan 0 >
Y tan
Xm Y2tan
X
=
Solving the differential equation the curve is found to be 2X Y 3Y= and tan 1 n
4 = = + , nI
but since4 = would be sufficient.
4
=
57.(D)When r rN and D are of opp sign, tan 0 <
2
Y tanXtan X Y 3Y
Y2tan
X
= =
and tan 1 =
8/8/2019 IIT Study Circle Paper1
13/14
AML
S
B N
T
K
O
4 =
, for Y 04
for Y 04
= > = =
(B) For f(x) to be have two equal roots,( )k 2 and f ( x ) f 2 0, k 1 = =
(C) For f(x) to be invertible ( )f ' x 0
8/8/2019 IIT Study Circle Paper1
14/14
x R k 2 = (D) For f(x) to have three real and distinct roots, ( ) ( )k 2, f x f 2 0 <
( )( )( )2
k 1 k 7k 7 4k 5 0k 4, 3, 2,6
+ + > =
60. (A) (r), (B) (s), (C) (q), (D) (q)
( ) ( )( )
1 11 1f x sin x tan x4x 1
x 1
= + + + + +
Domain of f(x) is [1, 1] a + b = 0
maximum value of g(x) is g(1) =
3
4 maximum value of h(x) occurs
When ( ) 4x 1x 1
+ + +is minimum
max value of ( ) 1h x4
=
Rang of f(x) is 3 ,14
3m 1
4 + = l 1
4=