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Rao IIT Academy / JEE - MAIN EXAM - 2017 / Solutions / CODE - B

Rao IIT Academy JEE MAIN EXAM 2017 Solutions / CODE B

Date: 02 Apr 2017

1.

Di�iculty : Easy

Topics :

Simple harmonic motion,

The period of K.E graph is half of the period of displacement graph.Comment :-The points on the graph on -axis should be di�erentiable.In all option mentioned, the graph has cusps at the points on -axis.

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2.

Di�iculty : Easy

Topics :

Physics,Heat and thermodynamics,

3.

Di�iculty : Medium

Topics :

Current electricity,

Null point does not change

4. Di�iculty : Easy

Topics :

Surface tension,



5.

Di�iculty : Easy

Topics :

Physics,

Topic - Communication System will not be there in the frequencies.

6.

Di�iculty : Easy

Topics :

Ray Optics,

Diverging lens forms the image at its focus. The image formed by diverging lens in the object to converging lens. Distance of the object from converging lens is i.e., object is at double focal point.

Image forms at double focal point on the other side of the lens.

7.

Di�iculty : Easy

Topics :

Rotational Mechanics,




Topics :

Modern Physics,

or

The graph of Vs is as follows

9.

Di�iculty : Easy

Topics :

Modern Physics,

no. of undecayed nucleus no. of decyaed nucleus is



10.


Topics :

Electrostatics,

Since dipole moment is in

planeConsider

According to the problem

11.

Di�iculty : Easy

Topics :

Physics,

Topic - SemiconductorVoltage gain of the amplifier is

-Ve sign indicates phase di�erence is

12.

Di�iculty : Easy

Topics :

Physics,Heat and thermodynamics,

for hydrogen

for nitrogen




Topics :

Caloriemetry,

Heat lost by ball = Heat gain by calmimetre and water

14.

Di�iculty : Easy

Topics :

Work ,Energy and power,

15.

Di�iculty : Easy

Topics :


or

or or or



16. Di�iculty : Medium

Topics :

Rotational Mechanics,

Torque of gravity about

or

17.

Di�iculty : Easy

Topics :

Modern Physics,

18.


Topics :

Elasticity,



19.

Di�iculty : Easy

Topics :

Electromagnetic Induction( EMI ),

or

or

or

or

or

20.

Di�iculty : Easy

Topics :

Wave optics,

4th Bright of will coincide with 5th bright of




Topics :

Physics,

Topic : Classical Magnetism

Time period

22.

Di�iculty : Easy

Topics :

Gravitation,

The desired graph is

23.

Di�iculty : Easy

Topics :


P.d across each resistor is zero. Hence correct is zero in each resistor.




Topics :

Modern Physics,

25.

Di�iculty : Easy

Topics :

Elasticity,

and

or

26.

Di�iculty : Easy

Topics :

Work ,Energy and power,

or

or

or

or At



27.


Topics :

Wave optics,

28.

Di�iculty : Easy

Topics :


By KVL : -

So charge on capacitor is

29.

Di�iculty : Easy

Topics :

Capacitors,

8 rows, then Get

So minimum of capacitors are



30.

Di�iculty : Easy

Topics :

Kinematics,

Velocity becomes negative a�er same time and the negative slope is constant.


Topics :

Straight lines,

or as

Triangle has co-ordinates

As one side is horizontal one altitude will be vertical arthocentre




Topics :

Quadratic Equations,

as

33.


Topics :

Functions,One-One Function (Injection),Onto Function (Surjection),

is many one

Range = Co-domain



34.

T T T F T T TT F F F T F TF T T T T T TF F T T F T T

Di�iculty : Easy

Topics :

Math,

Topic : Mathematical Reasoning Hence it is aTautology.Alternate :

35.


Topics :

Determinants & Matrices,Cramer's Rule,

As system no solution then

when then both equation and obeserv that if then no solutionsif then infinite solutions



36.

Di�iculty : Di�icult

Topics :

Math,Area under curve,

Required area

37.


Topics :

Sequence & Series,

are in AP



38.


Topics :

Permutations & Combinations,

39.


Topics :

Application of derivatives,

Equation of normal at will be which is satisfied by only in the given options.



40.


Topics :

Math,Conic Sections,

Which is satisfied by

41.


Topics :

Sequence & Series,Functions,



42.


Topics :

Math,Vectors,

Using (2) in (1) we have


Topics :

Math,

Topic : Height & Distance




Topics :

Application of derivatives,

45.

Di�iculty : Easy

Topics :

Math,Definite integration,



46.

Di�iculty : Easy

Topics :

Di�erential Equations,

...(I)

I.F. of equation (I) is Hence answer is

As So

Now

47.

Di�iculty : Easy

Topics :

Math,Indefinite integration,

(Put n = 4)



48.

Di�iculty : Easy

Topics :

Complex Numbers,Cube roots of unity,

i.e. is non-real cube root of unity

and

49.

Di�iculty : Easy

Topics :

Binomial Theorem,

50.

Di�iculty : Easy

Topics :

Limits,



51.


Topics :

Math,Trigonometric Ratios & Identities,

52.


Topics :

Math,Three Dimensional Geometry,

Line PQ parallel to

As point R lies on plane then

Hence point R is (2, 2, 8)



53.

Di�iculty : Easy

Topics :

Math,Three Dimensional Geometry,

Normal perpendicular to both the lines

Normal vector parallel to perpendicular

where

Hence equation of plane is

Now distance from point (1, 3, -7) to the plane is

54.


Topics :

Math,Di�erentiation of one function with respect to another function,

Put and

as



55.


Topics :

Circles,Conic Sections,

If the radius of circle is r, then its centre will be

In an isoscales right angled above,

56.

Di�iculty : EasyTopics :Math,Probability,

n = number of trials = 10

p = probability of drawing green ball

= probability of success

q = probability of failure

As the trials are Bernoulli trials, variance = npq



Remark : Observe that the required circle does not have to touch both the rays hence the radius of such circle can be as small as one wishes. Hence minimum radius does not exist. (However infimum radius is zero.)

57.

Di�iculty : Easy

Topics :

Conic Sections,

and

Again

Hence equation of ellipse is

and equation of normal at point is:

Equation of normal at point

is


Topics :

Math,Probability,

Two di�erent numbers are taken from the set

Let x + y = 4m ......(II)x - y = 4n ............ (III), x > yNow x = 2(m+n) y = 2(m-n)Hence both x and y are even numbers Then x and y are both in form of 4k or 4k + 2So order pair of (x, y) are

So Probability



59.


Topics :

Math,Probability,

P(Exactly one of A or B occurs)

Adding all three

P (Atleast one event occurs) =

60.

Di�iculty : Easy

Topics :

Determinants & Matrices,Adjoint of square Matrix,

61.


Topics :

Chemistry,

Topic - Nitrogen containing compoundsAniline undergoes protination in con , so it undergoes metanitration



62.

Di�iculty : Easy

Topics :

Chemistry,Thermodynamics,

From First law of Thermodynamics

for an Adiabatic process

63.

Di�iculty : Easy

Topics :

Chemistry,

Topic - AlkylhalidesRate of stabiling



64.

Di�iculty : Easy

Topics :

Chemistry,Atomic Structure,

; n = orbit number,


Topics :

Chemistry,Ionic equilibrium,

For the hydrolysis of a salt of weak acid and weak base

66.


Topics :

Chemistry,Polymers,

Nylon - 6 is prepared from caprolactum,caprolactum on hydrolysis it gives aminocarboxylicacid it undergoes polymerisation toform Nylon - 6

67.


Topics :

Chemistry,Mole concept,

is by mass is kgs

It replaced by weight is doubled i.e., kg kg increase




Topics :

Chemistry,

Topic - AlkylhalidesTo shown decolourisation compound must be unsaturated

69.


Topics :

Chemistry,d-block,

70.


Topics :

Chemistry,S-block,

form basic carbonate while lithium from normal carbonate .

71.

Di�iculty : Easy

Topics :

Chemistry,

Topic - Hydrocarbons

Product contains two chiral carbons so, 4 S.I




Topics :

Chemistry,Solid State,

Distance of closest approach

73.


Topics :

Chemistry,Chemical Kinetics,

(At 300K)



74.


Topics :

Chemistry,CARBONYLS,

75.

Di�iculty : Easy

Topics :

Chemistry,Surface Chemistry,

Tyndall e�ect is observed when (1) The diameter fo the dispersed particle is not much smaller than the wavelength of the light used.(2) The refractive indices of the dispersed phase and dispersion medium di�er greatly in magnitude.

76.


Topics :

Chemistry,

Topic - Carbohydrates

Sugar with hemiacetal are reducing sugar.



77.

Di�iculty : Easy

Topics :

Chemistry,

Topic : Thermochemistry .....(1)

....(2)

.....(3)(1)+2 (2) and +(3)

78.


Topics :

Chemistry,P-block,

79.


Topics :

Chemistry,S-block,

cold - dil

80.

Di�iculty : Easy

Topics :

Chemistry,

Topic - Hydrocarbons



81.


Topics :

Chemistry,

Topic : Qualitative analysis

is responsible for decolourisation of acidic solution of .


Topics :

Chemistry,Chemical Bonding,

is diamagnetic only and has bond order 3.0. Rest all are paramagnetic

83.


Topics :

Chemistry,Solutions,

Since,

or



84.

Di�iculty : Easy

Topics :

Chemistry,GOC,

Non aromatic compunds are less stable than aromatic

85.


Topics :

Chemistry,

Topic : coordination

No of moles of ions

moles. moles of gives moles of ions

No. of outside the co - ordination sphere should be 2

86.


Topics :

Chemistry,CARBONYLS,

DIBAL-H can reduce esters only, not carboxylicacids



87.


Topics :

Chemistry,

Topic : Environmental science ppm causes brown mottling of teeth

ppm causes laxative ppm causes blue baby syndrome.

88.


Topics :

Chemistry,Mole concept,


Topics :

Chemistry,Electrochemistry,

,

Strongest reducing agent is the atom/ ion which is easily oxidised i.e. having the largest value of standard oxidation potential(SOP)

is the maximum value.


Topics :

Chemistry,

Topic : Periodic properties in each species (all are isoelectronic).



rao iit academy date: 02 apr 2017 jee main exam … iit academy / jee - main exam - 2017 / solutions...

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