Post on 11-Feb-2020
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
/ JEE MAINOFFICIAL ONLINE
EXAM / 9 January19Slot II / Solutions
Date: 09 Jan 2019
Rao IIT Academy Website : www.raoiit.com1
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
1. Di�iculty : Medium
Topics :
Simple harmonic motion,
Rao IIT Academy Website : www.raoiit.com2
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
2. Di�iculty : Medium
Topics :
Modern Physics,
If particle making circular path in magnetic field.
then ____________(I)
if particle path is straight line in magnetic and electric field. Only possible when magentic force is equal electric field force onthe particle
i.e _____________ (II)
From (I) and (II)
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RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
3.Di�iculty : Medium
Topics :
Modern Physics,
At
4. Di�iculty : Easy
Topics :
Ray Optics,
Angle between two mirror will be
Rao IIT Academy Website : www.raoiit.com4
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
5.Di�iculty : Medium
Topics :
Simple harmonic motion,
P.E = K.E
or
Position of the particle at
Rao IIT Academy Website : www.raoiit.com5
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
6.Di�iculty : Easy
Topics :
Kinematics,
___________ (I)
___________ (II)
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RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
7. Di�iculty : Medium
Topics :
Electrostatics,
Rao IIT Academy Website : www.raoiit.com7
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
8. Di�iculty : Medium
Topics :
Physics,
As use know,
9.Di�iculty : Easy
Topics :
ELECTROMAGNETISM,
Energy associated with electric field and with magnetic field is same for electromagnetic wave in free space.
Rao IIT Academy Website : www.raoiit.com8
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
10.Di�iculty : Medium
Topics :
Semiconductors,
then,
________ (I)
If diode connect are reversed then
then
__________ (II)
Change in
Rao IIT Academy Website : www.raoiit.com9
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
11.Di�iculty : Medium
Topics :
Gravitation,
Energy required to take a satellite to heigh
_______________ (I)
Kinetic energy required for the satellite to be in circular path is
________ ( II)
Rao IIT Academy Website : www.raoiit.com10
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
12. Di�iculty : Medium
Topics :
Communication systems,
Available 1% frequency as a signal band
No. of channels accomodated for transmitting TV signals
13. Di�iculty : Easy
Topics :
Thermodynamics,
Amount of heat transfer
Rao IIT Academy Website : www.raoiit.com11
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
14.Di�iculty : Medium
Topics :
Physics,
Here, +ve zero error
True reading = (Main scale) + (Circular L.C) - (+ve error)
15. Di�iculty : Easy
Topics :
Units,Dimensions & Error analysis,
Units of
By elimination method
Rao IIT Academy Website : www.raoiit.com12
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
16. Di�iculty : Easy
Topics :
Current electricity,
Power
Power
Heat energy
Rao IIT Academy Website : www.raoiit.com13
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
17.Di�iculty : Easy
Topics :
Current electricity,
current in CDEF branch is
Voltage drop across is
Total potential drop across CF or DE is
Potential drop across BC =
Total current
Rao IIT Academy Website : www.raoiit.com14
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
18. Di�iculty : Easy
Topics :
Sound wave,
for given pipe, frequency for second harmonic,
appearent frequency heard by running person
19. Di�iculty : Medium
Topics :
Wave optics,
Number of bright fringes ( just above the C.M.)
Total no. of bright frings =
Rao IIT Academy Website : www.raoiit.com15
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
20. Di�iculty : Easy
Topics :
Current electricity,
21.Di�iculty : Medium
Topics :
Current electricity,
BONUS
22.Di�iculty : Easy
Topics :
Current electricity,
Resistance
Rao IIT Academy Website : www.raoiit.com16
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
23. Di�iculty : Easy
Topics :
Work ,Energy and power,
Let's findout acceleration is constant or variable.
...(a = const)
displacement in 1st 5 sec
24. Di�iculty : Di�icult
Topics :
Photoelectric e�ect,
....I
work function = 4.7 = eV
for maximum K.E.,
We know,
for max. K.E. we will take
Rao IIT Academy Website : www.raoiit.com17
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
25.Di�iculty : Di�icult
Topics :
Electrostatics,
Rao IIT Academy Website : www.raoiit.com18
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
26. Di�iculty : Easy
Topics :
Newton's Laws of motion,
and
... (for equilibrium)
...(i)
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RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
27. Di�iculty : Medium
Topics :
Thermodynamics,
If then
Rao IIT Academy Website : www.raoiit.com20
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
28. Di�iculty : Medium
Topics :
MAGNETISM,
(1) Circular loop :
...(i)
(2) Circular coil :
...(ii)
From (i) and (ii)
Rao IIT Academy Website : www.raoiit.com21
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
29.Di�iculty : Medium
Topics :
Simple harmonic motion,
As
So
As
So
30.Di�iculty : Medium
Topics :
Rotational Motion,
Rao IIT Academy Website : www.raoiit.com22
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
1. Di�iculty : Easy
Topics :
Chemical Kinetics,
Products
....(1)
both A and B doubled
.....(2)
Only A is doubled
....(3)
from (1) and (3)
2. Di�iculty : Medium
Topics :
Aldehydes,Ketones,
3. Di�iculty : Easy
Topics :
d-block,F-block,
Zn has lowest enthalpy of atomisation due to very weak metallic bonding due to absence of unpaired d-electron.
Rao IIT Academy Website : www.raoiit.com23
CHEMISTRY
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
4. Di�iculty : Medium
Topics :
AMINES,
pKa Basicity
5. Di�iculty : Di�icult
Topics :
Nitrogen containing compounds,
6. Di�iculty : Medium
Topics :
Electrochemistry,
Rao IIT Academy Website : www.raoiit.com24
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
7.Di�iculty : Easy
Topics :
PERIODIC PROPERTIES,
Second electron gain enthalpy is positive as energy needs to be applied to add to a negatively charge ion.
8. Di�iculty : Medium
Topics :
Aldehydes,
9. Di�iculty : Medium
Topics :
Nitrogen containing compounds,
Rao IIT Academy Website : www.raoiit.com25
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
10.Di�iculty : Easy
Topics :
GOC,
11. Di�iculty : Di�icult
Topics :
STRUCTURE OF ATOM,
Order of spread of orbitals
Same is order of decreasing orbital angular momentum.
Statement (A) is correct
for distribution peak of orbitals shi�s towards le� / decreasing
Statement (B) is correct. Hence option (1) is correct.
12. Di�iculty : Easy
Topics :
Environmental Chemistry,
pH of rain water is 5.6 due to formation of carbonic acid is atmosphere
Rao IIT Academy Website : www.raoiit.com26
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
13. Di�iculty : Easy
Topics :
Coordination Compounds,
Higher absorbed wavelength weaker the ligand.
14.Di�iculty : Di�icult
Topics :
Thermodynamics,
15.Di�iculty : Medium
Topics :
Solid State,
density of copper crystal.
Edge length
16. Di�iculty : Medium
Topics :
Coordination Compounds,
is a strong field ligand hence will come higher splitting energy.
Rao IIT Academy Website : www.raoiit.com27
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
17.Di�iculty : Di�icult
Topics :
Solutions,
(Ice separated)
18.Di�iculty : Easy
Topics :
P-block-II,
has tow bonds
19. Di�iculty : Medium
Topics :
Chemical Bonding,
bond order paramagnetic
bond order diamagnetic.
20. Di�iculty : Medium
Topics :
Aldehydes,Ketones,
(a) 2,4- DNP test : Coloured compound : group may be aldehyde (or) ketone
(b) Iodoform test : Yellow precipitate presence of methyl ketone
(c) Azodye test : No dye formation : Nitrogen of amine does not involve in diazotisation hence no dye formation.
Rao IIT Academy Website : www.raoiit.com28
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
21.Di�iculty : Easy
Topics :
S-block,
is only group 1 element which forms nitrides.
22. Di�iculty : Medium
Topics :
BIOMOLECULES ,
23.Di�iculty : Medium
Topics :
Metallurgy,
Using given elignham diagram.
can reduce at all temperatures.
24. Di�iculty : Medium
Topics :
Environmental Chemistry,
Methemoglobinemia is caused by nitrates in water.
255. Di�iculty : Easy
Topics :
PRACTICAL ORGANIC CHEMISTRY,
Benzaldehyde -Absorbate
Alumina - Adsorbent
Acetonitrile - Colourless liquid - Mobile phase in chromatography. It is simplest organic nitrile used as polar aprotic solvent.
Rao IIT Academy Website : www.raoiit.com29
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
26.Di�iculty : Easy
Topics :
Chemical equilibrium,
27. Di�iculty : Easy
Topics :
Mole concept,
is
moles produce moles
moles produce moles
28. Di�iculty : Easy
Topics :
Hydrogen & Its compound,
Temporary hardness is due to presence of bicarbonates of calcium and magnesium.
29. BDi�iculty : Easy
Topics :
Surface Chemistry,
solution is negatively charged sol so by using hardy-Schulze rule large charge on cation is required for e�ectivecoagulation. will be the answer.
Rao IIT Academy Website : www.raoiit.com30
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
30. Di�iculty : Di�icult
Topics :
CARBOXYLIC ACIDS AND ITS DERIVATIVES,
In presence of lewis acid electrophile attacks the benzene ring.
1.Di�iculty : Medium
Topics :
Straight lines,
Equation of ...(i)
is point of intersection of and and and ispoint of intersection and .
Find point and , then
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MATHEMATICS
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
2. Di�iculty : Medium
Topics :
Sequence & Series,
Rao IIT Academy Website : www.raoiit.com32
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
3. Di�iculty : Medium
Topics :
Vectors,
...(i)
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RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
4.Di�iculty : Medium
Topics :
Indefinite integration,
Rao IIT Academy Website : www.raoiit.com34
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
5.Di�iculty : Medium
Topics :
ContinuityDi�erentiability & Derivatives,
and
when point is
Now eliminating
again di�. :
6. Di�iculty : Easy
Topics :
Inverse Trigonometric Functions,
Rao IIT Academy Website : www.raoiit.com35
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
7. Di�iculty : Easy
Topics :
Hyperbola,
Hyperbola : ...(i)
(i) contains
8. Di�iculty : Easy
Topics :
Sequence & Series,
Let be first term of A.P. and be common di�erence.
...(i)
...(ii)
...(iii)
in G.P.
Rao IIT Academy Website : www.raoiit.com36
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
9. Di�iculty : Medium
Topics :
Area bounded by the curves,
(region above x-axis including x-axis)
10. Di�iculty : Medium
Topics :
Binomial Theorem,
Coe�. of in
Coe�. of in
Coe�. of in
Rao IIT Academy Website : www.raoiit.com37
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
11. Di�iculty : Medium
Topics :
Complex Numbers,
is root of i.e or
12. Di�iculty : Medium
Topics :
MATRICES,
Rao IIT Academy Website : www.raoiit.com38
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
13.Di�iculty : Medium
Topics :
Trigonometric Equations,
then
14.Di�iculty : Medium
Topics :
Three Dimensional Geometry,
Rao IIT Academy Website : www.raoiit.com39
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
15. Di�iculty : Medium
Topics :
Three Dimensional Geometry,
Plane containing
--------- (1)
Required plane : ------(2)
No. (2) contains
(1) & (2) are
16. Di�iculty : Medium
Topics :
PERMUTATION AND COMBINATION,
using symmetricity
Rao IIT Academy Website : www.raoiit.com40
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
17. Di�iculty : Easy
Topics :
Quadratic Equations,
roots real & distined
------(1)
considering roots lie in
-------- (2)
---- (3)
----(4)
using &
18. Di�iculty : Easy
Topics :
Quadratic Equations,
for roots to be rational, D should be non-negative perfect square and given as positive integer.
but does not give D as perfect square
So,
Rao IIT Academy Website : www.raoiit.com41
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
19.Di�iculty : Medium
Topics :
ContinuityDi�erentiability & Derivatives,Definite integration,
is a constant function
as
20.Di�iculty : Medium
Topics :
Application of derivatives,Conics,
area
Max. area
Rao IIT Academy Website : www.raoiit.com42
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
21.Di�iculty : Medium
Topics :
Probability,
Probability that IInd ball is red
22.Di�iculty : Medium
Topics :
Definite integration,
23. Di�iculty : Medium
Topics :
Di�erential Equations,
put but
is constant
Rao IIT Academy Website : www.raoiit.com43
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
24. Di�iculty : Medium
Topics :
Limits,
25. Di�iculty : Medium
Topics :
Circles,
: family of circle with centre at & variable radius.
Distance between centre:
26.Di�iculty : Medium
Topics :
Permutations & Combinations,
Number of natural numbers less than 7000 using 0,1,3,7,9 (rep. allowed)
Single digit : 4
two digit : 4.5 =20
Three digit : 4.5 .5 = 100
4 digit but less than 7000 : 2.5.5.5 =250
So no. are : 250 +100 +20 +4=374.
Rao IIT Academy Website : www.raoiit.com44
RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
27.Di�iculty : Medium
Topics :
Determinants & Matrices,
---------(1)
-------(2)
-------(3)
System is consistent
28.Di�iculty : Easy
Topics :
STATISTICS,
--------(1)
-------(2)
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RAO IIT ACADEMY / JEE - MAIN OFFICIAL ONLINE EXAM / 9 January-19 Slot- II / Solutions
29.Di�iculty : Medium
Topics :
Functions,
Function is injective but not surjective.
30. Di�iculty : Medium
Topics :
Mathematical reasoning,
Rao IIT Academy Website : www.raoiit.com46