Two bodies of masses and are connected by a light string going over a smooth light pulley on a smooth inclined plane as shown in the figure. The system is at rest. The force exerted by the inclined plane on the body of mass will be : [Take


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.
Two bodies of masses and are connected by a light string going over a smooth light pulley on a smooth inclined plane as shown in the figure. The system is at rest. The force exerted by the inclined plane on the body of mass will be : [Take

Match List I with List II.
| List I | List II | ||
|---|---|---|---|
| A. | Torque | I. | Nms |
| B. | Stress | II. | J kg |
| C. | Latent Heat | III. | Nm |
| D. | Power | IV. | Nm |
Choose the correct answer from the options given below :
The vertical component of the earth's magnetic field is at any place where the angle of dip is . The earth's resultant magnetic field at that place will be Given
The velocity of a small ball of mass and density when dropped in a container filled with glycerine becomes constant after some time. If the density of glycerine is , then the value of viscous force acting on the ball will be , The value of is _________. [use
A juggler throws balls vertically upwards with same initial velocity in air. When the first ball reaches its highest position, he throws the next ball. Assuming the juggler throws n balls per second, the maximum height the balls can reach is
A tube of length is filled completely with an incompressible liquid of mass and closed at both ends. The tube is then rotated in horizontal plane about one of its ends with a uniform angular velocity . If be the force exerted by the liquid at the other end then the value of will be __________.
A ball is released from a height h. If and be the time required to complete first half and second half of the distance respectively. Then, choose the correct relation between and .
The metallic bob of simple pendulum has the relative density 5. The time period of this pendulum is . If the metallic bob is immersed in water, then the new time period becomes s. The value of will be ________.
A Zener diode along with a series resistance is connected across a supply (as shown in the figure). If the maximum Zener current is , then the minimum value of R will be _______ .

Nearly 10% of the power of a light bulb is converted to visible radiation. The change in average intensities of visible radiation, at a distance of from the bulb to a distance of is . The value of 'a' will be _________.
A modulating signal is added to the carrier signal for amplitude modulation. The combined signal is passed through a non-linear square law device. The output is then passed through a band pass filter. The bandwidth of the output signal of band pass filter will be _________ .
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: Alloys such as constantan and manganin are used in making standard resistance coils.
Reason R: Constantan and manganin have very small value of temperature coefficient of resistance.
In the light of the above statements, choose the correct answer from the options given below.
The root mean square speed of smoke particles of mass in their Brownian motion in air at NTP is approximately. [Given ]
The speed of a transverse wave passing through a string of length and mass is . The area of cross-section of the wire is and its Young's modulus is . The extension of the wire over its natural length due to its tension will be . The value of is __________.
A circuit element when connected to an a.c. supply of peak voltage gives a peak current of which is in phase with the voltage. A second element when connected to the same a.c. supply also gives the same value of peak current which lags behind the voltage by . If and are connected in series to the same supply, what will be the rms value of the current in ampere?
If momentum of a body is increased by 20%, then its kinetic energy increases by
An unpolarised light beam of intensity is passed through a polaroid P and then through another polaroid Q which is oriented in such a way that its passing axis makes an angle of relative to that of P. The intensity of the emergent light is
Light enters from air into a given medium at an angle of with interface of the air-medium surface. After refraction, the light ray is deviated through an angle of from its original direction. The refractive index of the medium is:
A capacitor of capacitance 500 F is charged completely using a dc supply of 100 V. It is now connected to an inductor of inductance 50 mH to form an LC circuit. The maximum current in LC circuit will be _______ A.
Read the following statements :
(A) Volume of the nucleus is directly proportional to the mass number.
(B) Volume of the nucleus is independent of mass number.
(C) Density of the nucleus is directly proportional to the mass number.
(D) Density of the nucleus is directly proportional to the cube root of the mass number.
(E) Density of the nucleus is independent of the mass number.
Choose the correct option from the following options.
A metal wire of length and cross-sectional area has breaking stress . A block of is attached at one end of the string and is rotating in a horizontal circle. The maximum linear velocity of block will be _________ .
A long wire is broken into two unequal parts and . The part of the wire is streched into another wire W. Length of is twice the length of and the resistance of is twice that of . Find the ratio of length of and .
A wire X of length carrying a current of is placed parallel to a long wire of length . The wire carries a current of . The distance between two wires is and currents flow in the same direction. The force acting on the wire is

A thermodynamic system is taken from an original state D to an intermediate state E by the linear process shown in the figure. Its volume is then reduced to the original volume from E to F by an isobaric process. The total work done by the gas from D to E to F will be

Two radioactive materials A and B have decay constants and respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of B to that of A will be "e" after a time . The value of a is _________.
An particle and a proton are accelerated from rest through the same potential difference. The ratio of linear momenta acquired by above two particles will be:
The torque of a force about the origin is . If the force acts on a particle whose position vector is , then the value of will be
Two identical thin metal plates has charge and respectively such that . The plates were brought close to each other to form a parallel plate capacitor of capacitance C. The potential difference between them is :
Two identical metallic spheres and when placed at certain distance in air repel each other with a force of . Another identical uncharged sphere is first placed in contact with and then in contact with and finally placed at midpoint between spheres A and B. The force experienced by sphere C will be:
An object of mass is taken to a height from the surface of earth which is equal to three times the radius of earth. The gain in potential energy of the object will be [If, and radius of earth ]
When coal of purity 60% is allowed to burn in presence of insufficient oxygen, 60% of carbon is converted into 'CO' and the remaining is converted into ''. The heat generated when of coal is burnt is _________.
In liquation process used for tin (Sn), the metal :
When ethanol is heated with conc. , a gas is produced. The compound formed, when this gas is treated with cold dilute aqueous solution of Baeyer's reagent, is
Which of the following is NOT a natural polymer?
'x' g of molecular oxygen is mixed with of neon (Ne). The total pressure of the non-reactive mixture of and Ne in the cylinder is 25 bar. The partial pressure of Ne is 20 bar at the same temperature and volume. The value of 'x' is _________.
[Given: Molar mass of .
Molar mass of ]
The Hinsberg reagent is




A compound 'X' is a weak acid and it exhibits colour change at pH close to the equivalence point during neutralization of NaOH with . Compound 'X' exists in ionized form in basic medium. The compound 'X' is
Compound 'A' undergoes following sequence of reactions to give compound 'B'.
The correct structure and chirality of compound 'B' is
[where Et is





Given below are the critical temperatures of some of the gases:
| Gas | Critical temperature (K) |
|---|---|
| He | 5.2 |
| CH | 190.0 |
| CO | 304.2 |
| NH | 405.5 |
The gas showing least adsorption on a definite amount of charcoal is
Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: Amylose is insoluble in water.
Reason R: Amylose is a long linear molecule with more than 200 glucose units.
In the light of the above statements, choose the correct answer from the options given below.
Consider the reaction
The amount of required to produce of is
(Given: Atomic masses of and are and 39, respectively.)
Given below are two statements.
Statement I : Stannane is an example of a molecular hydride.
Statement II : Stannane is a planar molecule.
In the light of the above statement, choose the most appropriate answer from the options given below.
Octahedral complexes of copper(II) undergo structural distortion (Jahn-Teller). Which one of the given copper (II) complexes will show the maximum structural distortion? (en - ethylenediamine; )
of is mixed with of . The of the mixture is _________.
Given:
Consider, and .
Amongst the above molecule(s)/ion(s), the number of molecule(s)/ion(s) having hybridisation is __________.
Given below are the quantum numbers for 4 electrons.
A.
B.
C.
D.
The correct order of increasing energy is
Portland cement contains 'X' to enhance the setting time. What is 'X'?
Which of the following -metal ion will give the lowest enthalpy of hydration when dissolved in water ?
Dinitrogen is a robust compound, but reacts at high altitudes to form oxides. The oxide of nitrogen that can damage plant leaves and retard photosynthesis is :
When borax is heated with on a platinum loop, blue coloured bead formed is largely due to :
Given below are two statements.
Statement I : The compound
is optically active.
Statement II :
is mirror image of above compound A.
In the light of the above statement, choose the most appropriate answer from the options given below.
Correct structure of -methylcyclohexane carbaldehyde is




For a cell,
the cell potential is found to be at . The magnitude of standard electrode potential for is _________ .
[Given : = 0.80 V and = 0.06 V]
Assuming of trace radioactive element X with a half life of 30 years is absorbed by a growing tree. The amount of X remaining in the tree after 100 years is ______ .
[Given : ln 10 = 2.303; log 2 = 0.30]
of solute A was dissolved in of ethanol and freezing point of the solution was found to be . The molar mass of solute A is ________ g .
[Given : Freezing point of ethanol is 156.0 K.
Density of ethanol is 0.80 g cm3.
Freezing point depression constant of ethanol is 2.00 K kg mol1]
A 1.84 mg sample of polyhydric alcoholic compound 'X' of molar mass 92.0 g/mol gave 1.344 mL of gas at STP. The number of alcoholic hydrogens present in compound 'X' is ________.
Sum of oxidation state (magnitude) and coordination number of cobalt in is _________.

Consider the following sulphur based oxoacids.
and .
Amongst these oxoacids, the number of those with peroxo bond is ________.
The number of chlorine atoms in bithionol is __________.
The number of stereoisomers formed in a reaction of with is ___________.
where is ]
If the tangent to the curve at the point is also tangent to the curve at the point (2, 1), then is equal to __________.
The sum and product of the mean and variance of a binomial distribution are 82.5 and 1350 respectively. Then the number of trials in the binomial distribution is ____________.
and . Then is equal to __________.
Let be three coplanar concurrent vectors such that angles between any two of them is same. If the product of their magnitudes is 14 and , then is equal to :
If the solution curve of the differential equation passes through the points and , then
Let . Then the set of all values of , for which for some , is :
The number of natural numbers lying between 1012 and 23421 that can be formed using the digits (repetition of digits is not allowed) and divisible by 55 is _________.
________.
Then is equal to
The number of elements in the set is :
The domain of the function is :
Let be the roots of the quadratic equation If , , then is equal to __________.
Let be the slopes of two adjacent sides of a square of side a such that . If one vertex of the square is , where and the equation of one diagonal is , then is equal to :
The statement is NOT equivalent to
For , if , then
Let be a chord of length 12 of the circle . If tangents drawn to the circle at points and intersect at the point , then five times the distance of point from chord is equal to __________.
Bag I contains 3 red, 4 black and 3 white balls and Bag II contains 2 red, 5 black and 2 white balls. One ball is transferred from Bag I to Bag II and then a ball is drawn from Bag II. The ball so drawn is found to be black in colour. Then the probability, that the transferred ball is red, is :
Let and be two vectors such that and . Then is equal to __________.
Which of the following matrices can NOT be obtained from the matrix by a single elementary row operation ?
If be a complex number such that , then the maximum value of is :
Let and . For , if , then is equal to _______.
If and are coplanar, then the product of all possible values of is:
Let and be vertices of a . If is the circumcentre of , then which of the following is NOT correct about ?
Let be the foot of perpendicular drawn from the point to the plane . If is a point on the plane such that , then the area of is equal to :
If the system of equations
has infinitely many solutions, then is equal to
Let be the solution curve of the differential equation , which passes through the point . Then is equal to :
If denotes the greatest integer , then the number of points, at which the function is not differentiable in the open interval , is __________.
is equal to
If denotes the greatest integer , then the value of is :
Then is equal to