The amplitude of a particle executing SHM is . The displacement at which its kinetic energy will be more than the potential energy is: __________

Official solved question paper for Joint Entrance Examination (Main). Review all 90 questions, official answer keys, and detailed step-by-step solutions below, or attempt online with timer and negative marking.
The amplitude of a particle executing SHM is . The displacement at which its kinetic energy will be more than the potential energy is: __________
Find the magnetic field at the point in figure. The curved portion is a semicircle connected to two long straight wires.

A series LCR circuit is connected to an ac source of . The circuit contain a resistance and an inductor of inductive reactance . The capacitance of the capacitor needed to maximize the average rate at which energy is supplied will be _________ .
The average kinetic energy of a molecule of the gas is
A mercury drop of radius is broken into 125 equal size droplets. Surface tension of mercury is . The gain in surface energy is :
A block of mass is placed at rest on a table of rough surface. Now, if a force of is applied in the direction parallel to surface of the table, the block slides through a distance of in an interval of time . Coefficient of kinetic friction is (given, ):
A thin cylindrical rod of length is placed horizontally on the principle axis of a concave mirror of focal length . The rod is placed in a such a way that mid point of the rod is at from the pole of mirror. The length of the image formed by the mirror will be . The value of is _____________.
An object moves with speed and along a line segment AB, BC and CD respectively as shown in figure. Where AB = BC and AD = 3AB, then average speed of the object will be:

Which of the following frequencies does not belong to FM broadcast ?
A certain pressure '' is applied to 1 litre of water and 2 litre of a liquid separately. Water gets compressed to whereas the liquid gets compressed to . The ratio of Bulk modulus of water to that of the liquid is . The value of is ____________.
Let be the uniform surface charge density of two infinite thin plane sheets shown in figure. Then the electric fields in three different region and are:

A solid cylinder is released from rest from the top of an inclined plane of inclination and length . If the cylinder rolls without slipping, its speed upon reaching the bottom of the inclined plane is __________ . (Given )

Match List - I with List - II :
| List I | List II | ||
|---|---|---|---|
| A. | AC generator | I. | Presence of both L and C |
| B. | Transformer | II. | Electromagnetic Induction |
| C. | Resonance phenomenon to occur | III. | Quality factor |
| D. | Sharpness of resonance | IV. | Mutual Induction |
Choose the correct answer from the options given below :
The equivalent resistance between and of the network shown in figure;

The mass of proton, neutron and helium nucleus are respectively and . The binding energy of helium nucleus is :
represents the equation of state of some gases. Where is the pressure, is the volume, is the temperature and are the constants. The physical quantity, which has dimensional formula as that of , will be:
In an experiment to find emf of a cell using potentiometer, the length of null point for a cell of emf is found to be . If this cell is replaced by another cell of emf E, the length-of null point increases by . The value of is . The value of is ____________.
Match List I with List II :
| List I | List II | ||
|---|---|---|---|
| A. | Microwaves | I. | Radio active decay of the nucleus |
| B. | Gamma rays | II. | Rapid acceleration and deceleration of electron in aerials |
| C. | Radio waves | III. | Inner shell electrons |
| D. | X-rays | IV. | Klystron valve |
Choose the correct answer from the options given below :
Given below are two statements:
Statement I: Acceleration due to gravity is different at different places on the surface of earth.
Statement II: Acceleration due to gravity increases as we go down below the earth's surface.
In the light of the above statements, choose the correct answer from the options given below
'' polarizing sheets are arranged such that each makes an angle with the preceeding sheet. An unpolarized light of intensity I is incident into this arrangement. The output intensity is found to be . The value of will be:
A proton moving with one tenth of velocity of light has a certain de Broglie wavelength of . An alpha particle having certain kinetic energy has the same de-Brogle wavelength . The ratio of kinetic energy of proton and that of alpha particle is:
Match List I with List II:
| List I | List II | ||
|---|---|---|---|
| A. | Intrinsic semiconductor | I. | Fermi-level near the valence bond |
| B. | n-type semiconductor | II. | Fermi-level in the middle of valence and conduction band. |
| C. | p-type semiconductor | III. | Fermi-level near the conduction band |
| D. | Metals | IV. | Fermi-level inside the conduction band |
Choose the correct answer from the options given below :
A small particle moves to position from its initial position under the action of force . The value of work done will be __________ J.
A child stands on the edge of the cliff above the ground and throws a stone horizontally with an initial speed of . Neglecting the air resistance, the speed with which the stone hits the ground will be (given, ).
A charge particle of accelerated by a potential difference of enters a region of uniform magnetic field of magnitude at right angle to the direction of field. The charge particle completes semicircle of radius inside magnetic field. The mass of the charge particle is __________
If earth has a mass nine times and radius twice to that of a planet P. Then will be the minimum velocity required by a rocket to pull out of gravitational force of , where is escape velocity on earth. The value of is
A steel wire with mass per unit length is under tension of . The speed of transverse waves in the wire will be:
Two equal positive point charges are separated by a distance . The distance of a point from the centre of the line joining two charges on the equatorial line (perpendicular bisector) at which force experienced by a test charge becomes maximum is . The value of is __________.
A sample of gas at temperature is adiabatically expanded to double its volume. The work done by the gas in the process is :
A light of energy is incident on a hydrogen atom in its ground state. The atom absorbs the radiation and reaches to one of its excited states. The angular momentum of the atom in the excited state is . The value of is ___________ (use ).
25 mL of an aqueous solution of KCl was found to require 20 mL of 1 M solution when titrated using as an indicator. What is the depression in freezing point of KCl solution of the given concentration? _________ (Nearest integer).
(Given : )
Assume 1) 100% ionization and 2) density of the aqueous solution as 1 g mL
Resonance in carbonate ion is

Which of the following is true?
Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R
Assertion A : Hydrogen is an environment friendly fuel.
Reason R : Atomic number of hydrogen is 1 and it is a very light element.
In the light of the above statements, choose the correct answer from the options given below :
The total number of chiral compound/s from the following is ______________.

The correct representation in six membered pyranose form for the following sugar [X] is





How can photochemical smog be controlled?
A solution of when treated with gives a prussium blue precipitate due to the formation of :
Identify the incorrect option from the following




Highest oxidation state of Mn is exhibited in . The correct statements about are
(A) Mn is tetrahedrally surrounded by oxygen atoms.
(B) Mn is octahedrally surrounded by oxygen atoms.
(C) Contains Mn-O-Mn bridge.
(D) Contains Mn-Mn bond.
Choose the correct answer from the options given below :
The density of solution of is . Molality of the solution is ____________ . (Nearest integer).
Given: Molar mass of and is and respectively.
At , the enthalpy of the following processes are given :
What would be the value of X for the following reaction ? _____________ (Nearest integer)
Sum of oxidation states of bromine in bromic acid and perbromic acid is ___________.
Match List I with List II
| List I | List II | ||
|---|---|---|---|
| A. | Tranquilizers | I. | Anti blood clotting |
| B. | Aspirin | II. | Salvarsan |
| C. | Antibiotic | III. | antidepressant drugs |
| D. | Antiseptic | IV. | soframicine |
Choose the correct answer from the options given below:
A and B are two substances undergoing radioactive decay in a container. The half life of A is 15 min and that of B is 5 min. If the initial concentration of B is 4 times that of A and they both start decaying at the same time, how much time will it take for the concentration of both of them to be same? _____________ min.
Number of isomeric compounds with molecular formula which (i) do not dissolve in (ii) do not dissolve in . (iii) do not give orange precipitate with 2,4-DNP (iv) on hydrogenation give identical compound with molecular formula is ____________.
At what pH, given half cell will have electrode potential of 1.282 V? ___________ (Nearest Integer)
Given
Electrons in a cathode ray tube have been emitted with a velocity of 1000 m s. The number of following statements which is/are about the emitted radiation is ____________.
Given : .
(A) The de-Broglie wavelength of the electron emitted is 666.67 nm.
(B) The characteristic of electrons emitted depend upon the material of the electrodes of the cathode ray tube.
(C) The cathode rays start from cathode and move towards anode.
(D) The nature of the emitted electrons depends on the nature of the gas present in cathode ray tube.
Given below are two statements:
Statement I : Chlorine can easily combine with oxygen to form oxides; and the product has a tendency to explode.
Statement II : Chemical reactivity of an element can be determined by its reaction with oxygen and halogens.
In the light of the above statements, choose the correct answer from the options given below :
Which of the following represents the lattice structure of containing and ions?

Match List I with List II :
| List I | List II | ||
|---|---|---|---|
| A. | Slaked lime | I. | |
| B. | Dead burnt plaster | II. | |
| C. | Caustic soda | III. | |
| D. | Washing soda | IV. |
Choose the correct answer from the options given below :
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: In an Ellingham diagram, the oxidation of carbon to carbon monoxide shows a negative slope with respect to temperature.
Reason R: CO tends to get decomposed at higher temperature.
In the light of the above statements, choose the correct answer from the options given below
Match List I with List II
| List I | List II | ||
|---|---|---|---|
| Test | Functional group / Class of Compound | ||
| A. | Molisch's Test | I. | Peptide |
| B. | Biuret Test | II. | Carbohydrate |
| C. | Carbylamine Test | III. | Primary amine |
| D. | Schiff's Test | IV. | Aldehyde |
Choose the correct answer from the options given below :
But-2-yne is reacted separately with one mole of Hydrogen as shown below :

A. A is more soluble than B.
B. The boiling point & melting point of A are higher and lower than B respectively.
C. A is more polar than B because dipole moment of A is zero.
D. adds easily to B than A.
Identify the incorrect statements from the options given below :
(i)
(ii)
If the degree of dissociation and initial concentration of both the reactants and are equal, then the ratio of the total pressure at equilibrium is equal to . The value of is _____________ (Nearest integer)
Which of the following complex will show largest splitting of d-orbitals?
Choose the correct statement(s) :
A. Beryllium oxide is purely acidic in nature.
B. Beryllium carbonate is kept in the atmosphere of .
C. Beryllium sulphate is readily soluble in water.
D. Beryllium shows anomalous behaviour.
Choose the correct answer from the options given below :
Decreasing order of dehydration of the following alcohols is

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R
Assertion A: Amongst and ; 1 of activated charcoal adsorbs more of .
Reason R: The critical volume and critical pressure (atm) is highest for Krypton but the compressibility factor at critical point is lowest for Krypton.
In the light of the above statements, choose the correct answer from the options given below
In the following reaction, 'A' is





Which of the following are the example of double salt?
A.
B.
C.
D.
Choose the correct answer :
The value of is :
The shortest distance between the lines
and
is :
Let denote the set of all real values of such that the system of equations
is inconsistent, then \sum_\limits{\lambda \in S}\left(|\lambda|^{2}+|\lambda|\right) is equal to
is equal to
The sum of 10 terms of the series
is
Let be the set of all solutions of the equation . Then \sum_\limits{x \in S} 2 \sin ^{-1}\left(x^{2}-1\right) is equal to :
Let be a relation on , given by is an irrational number . Then is
In a binomial distribution , the sum and the product of the mean and the variance are 5 and 6 respectively, then is equal to :
Let and be a vector such that . If the minimum value of the scalar triple product \left[ {\matrix{ {\overrightarrow u } & {\overrightarrow v } & {\overrightarrow w } \cr } } \right] is , and where and are coprime natural numbers, then is equal to ____________.
If and , then the value of is equal to ____________.
Let the image of the point in the plane be .
Then the distance of the plane from the point is :
If is the solution curve of the differential equation
, then is equal to
Let . Then is equal to
Let and . Then
The combined equation of the two lines and can be written as
.
The equation of the angle bisectors of the lines represented by the equation is :
Let be an A.P. If the sum of its first four terms is 50 and the sum of its last four terms is 170 , then the product of its middle two terms is ___________.
If the center and radius of the circle are respectively and , then is equal to :
If the orthocentre of the triangle, whose vertices are (1, 2), (2, 3) and (3, 1) is , then the quadratic equation whose roots are and , is :
The remainder, when is divided by 49 , is ___________.
The number of 3-digit numbers, that are divisible by either 2 or 3 but not divisible by 7, is ____________.
The mean and variance of 5 observations are 5 and 8 respectively. If 3 observations are 1, 3, 5, then the sum of cubes of the remaining two observations is :
If \int_\limits{0}^{1}\left(x^{21}+x^{14}+x^{7}\right)\left(2 x^{14}+3 x^{7}+6\right)^{1 / 7} d x=\frac{1}{l}(11)^{m / n} where and are coprime then is equal to ____________.
and are the vertices of a quadrilateral . If its area is 18 square units, then is equal to __________.
The negation of the expression is equivalent to
For a triangle , the value of is least. If its inradius is 3 and incentre is M, then which of the following is NOT correct?
Let be the area bounded by the curve , the -axis and the ordinates and . Then is equal to ____________.
Let be a differentiable function such that f^{\prime}(x)+f(x)=\int_\limits{0}^{2} f(t) d t. If , then is equal to ____________.
The number of words, with or without meaning, that can be formed using all the letters of the word ASSASSINATION so that the vowels occur together, is ___________.
The area enclosed by the closed curve given by the differential equation
is .
Let and be the points of intersection of the curve and the -axis. If normals at and on the curve intersect -axis at points and respectively, then the length of the line segment is :
Let f(x) = \left| {\matrix{ {1 + {{\sin }^2}x} & {{{\cos }^2}x} & {\sin 2x} \cr {{{\sin }^2}x} & {1 + {{\cos }^2}x} & {\sin 2x} \cr {{{\sin }^2}x} & {{{\cos }^2}x} & {1 + \sin 2x} \cr } } \right|,\,x \in \left[ {{\pi \over 6},{\pi \over 3}} \right]. If and respectively are the maximum and the minimum values of , then