A person can throw a ball upto a maximum range of 100 m. How high above the ground he can throw the same ball?

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.
A person can throw a ball upto a maximum range of 100 m. How high above the ground he can throw the same ball?
A small spherical ball of radius 0.1 mm and density 104 kg m3 falls freely under gravity through a distance h before entering a tank of water. If, after entering the water the velocity of ball does not change and it continue to fall with same constant velocity inside water, then the value of h will be ___________ m.
(Given g = 10 ms2, viscosity of water = 1.0 105 N-sm2).
A block of mass M placed inside a box descends vertically with acceleration 'a'. The block exerts a force equal to one-fourth of its weight on the floor of the box. The value of 'a' will be
Two resistors are connected in series across a battery as shown in figure. If a voltmeter of resistance 2000 is used to measure the potential difference across 500 resistor, the reading of the voltmeter will be ___________ V.

A block of mass 40 kg slides over a surface, when a mass of 4 kg is suspended through an inextensible massless string passing over frictionless pulley as shown below.
The coefficient of kinetic friction between the surface and block is 0.02. The acceleration of block is. (Given g = 10 ms2.)

Starting with the same initial conditions, an ideal gas expands from volume V1 to V2 in three different ways. The work done by the gas is W1 if the process is purely isothermal, W2, if the process is purely adiabatic and W3 if the process is purely isobaric. Then, choose the correct option
At what temperature a gold ring of diameter 6.230 cm be heated so that it can be fitted on a wooden bangle of diameter 6.241 cm ? Both the diameters have been measured at room temperature (27C).
(Given : coefficient of linear thermal expansion of gold L = 1.4 105 K1)
A potential barrier of 0.4 V exists across a p-n junction. An electron enters the junction from the n-side with a speed of 6.0 105 ms1. The speed with which electron enters the p side will be ms1 the value of x is _____________.
(Given mass of electron = 9 1031 kg, charge on electron = 1.6 1019 C.)
The motion of a simple pendulum executing S.H.M. is represented by the following equation.
, where time is measured in second. The length of pendulum is
A small toy starts moving from the position of rest under a constant acceleration. If it travels a distance of 10m in t s, the distance travelled by the toy in the next t s will be :
In a double slit experiment with monochromatic light, fringes are obtained on a screen placed at some distance from the plane of slits. If the screen is moved by 5 102 m towards the slits, the change in fringe width is 3 103 cm. If the distance between the slits is 1 mm, then the wavelength of the light will be ____________ nm.
The half life of a radioactive substance is 5 years. After x years a given sample of the radioactive substance gets reduced to 6.25% of its initial value. The value of x is ____________.
If the electric potential at any point (x, y, z) m in space is given by V = 3x2 volt. The electric field at the point (1, 0, 3) m will be :
An inductor of 0.5 mH, a capacitor of 200 F and a resistor of 2 are connected in series with a 220 V ac source. If the current is in phase with the emf, the frequency of ac source will be ____________ 102 Hz.
The displacement current of 4.425 A is developed in the space between the plates of parallel plate capacitor when voltage is changing at a rate of 106 Vs1. The area of each plate of the capacitor is 40 cm2. The distance between each plate of the capacitor is x 103 m. The value of x is __________.
(Permittivity of free space, E0 = 8.85 1012 C2 N1 m2).
Two long current carrying conductors are placed to each other at a distance of 8 cm between them. The magnitude of magnetic field produced at mid-point between the two conductors due to current flowing in them is 300 T. The equal current flowing in the two conductors is :
The moment of inertia of a uniform thin rod about a perpendicular axis passing through one end is I1. The same rod is bent into a ring and its moment of inertia about a diameter is I2. If is , then the value of x will be ____________.
The Vernier constant of Vernier callipers is 0.1 mm and it has zero error of (0.05) cm. While measuring diameter of a sphere, the main scale reading is 1.7 cm and coinciding vernier division is 5. The corrected diameter will be _________ 102 cm.
In the following nuclear reaction,
D\buildrel \alpha \over \longrightarrow {D_1}\buildrel {{\beta ^ - }} \over \longrightarrow {D_2}\buildrel \alpha \over \longrightarrow {D_3}\buildrel \gamma \over \longrightarrow {D_4}
Mass number of D is 182 and atomic number is 74. Mass number and atomic number of D4 respectively will be _________.
In the given figure, the block of mass m is dropped from the point 'A'. The expression for kinetic energy of block when it reaches point 'B' is

The speed of light in media 'A' and 'B' are cm/s and cm/s respectively. A ray of light enters from the medium B to A at an incident angle ''. If the ray suffers total internal reflection, then
In an experiment to determine the velocity of sound in air at room temperature using a resonance tube, the first resonance is observed when the air column has a length of 20.0 cm for a tuning fork of frequency 400 Hz is used. The velocity of the sound at room temperature is 336 ms1. The third resonance is observed when the air column has a length of _____________ cm.
Two point charges Q each are placed at a distance d apart. A third point charge q is placed at a distance x from mid-point on the perpendicular bisector. The value of x at which charge q will experience the maximum Coulomb's force is :
The combination of two identical cells, whether connected in series or parallel combination provides the same current through an external resistance of 2. The value of internal resistance of each cell is
Given below are two statements :
Statement I : The electric force changes the speed of the charged particle and hence changes its kinetic energy; whereas the magnetic force does not change the kinetic energy of the charged particle.
Statement II : The electric force accelerates the positively charged particle perpendicular to the direction of electric field. The magnetic force accelerates the moving charged particle along the direction of magnetic field.
In the light of the above statements, choose the most appropriate answer from the options given below :
The time period of a satellite revolving around earth in a given orbit is 7 hours. If the radius of orbit is increased to three times its previous value, then approximate new time period of the satellite will be
The electric field at a point associated with a light wave is given by
E = 200 [sin (6 1015)t + sin (9 1015)t] Vm1
Given : h = 4.14 1015 eVs
If this light falls on a metal surface having a work function of 2.50 eV, the maximum kinetic energy of the photoelectrons will be
The TV transmission tower at a particular station has a height of 125 m. For doubling the coverage of its range, the height of the tower should be increased by
A capacitor is discharging through a resistor R. Consider in time t1, the energy stored in the capacitor reduces to half of its initial value and in time t2, the charge stored reduces to one eighth of its initial value. The ratio t1/t2 will be
A vessel contains 16g of hydrogen and 128g of oxygen at standard temperature and pressure. The volume of the vessel in cm3 is :
A 42.12% (w/v) solution of NaCl causes precipitation of a certain sol in 10 hours. The coagulating value of NaCl for the sol in 2 hours is :
[Given : Molar mass : Na = 23.0 g mol1 ; Cl = 35.5 g mol1]
The mixture of chloroxylenol and terpineol is an example of
Spin only magnetic moment of [MnBr6]4 is _________ B.M. (round off to the closest integer)
Elevation in boiling point for 1.5 molal solution of glucose in water is 4 K. The depression in freezing point for 4.5 molal solution of glucose in water is 4 K. The ratio of molal elevation constant to molal depression constant (Kb/Kf) is _________.
Given below are two statements.
Statement I : In CuSO4 . 5H2O, Cu-O bonds are present.
Statement II : In CuSO4 . 5H2O, ligands coordinating with Cu(II) ion are O-and S-based ligands.
In the light of the above statements, choose the correct answer from the options given below.
Using the rules for significant figures, the correct answer for the expression will be
The structure of protein that is unaffected by heating is

The stable carbocation formed in the above reaction is

Which of the following is the correct plot for the probability density (r) as a function of distance 'r' of the electron from the nucleus for 2s orbital?




A box contains 0.90 g of liquid water in equilibrium with water vapour at 27C. The equilibrium vapour pressure of water at 27C is 32.0 Torr. When the volume of the box is increased, some of the liquid water evaporates to maintain the equilibrium pressure. If all the liquid water evaporates, then the volume of the box must be __________ litre. [nearest integer]
(Given : R = 0.082 L atm K1 mol1)
(Ignore the volume of the liquid water and assume water vapours behave as an ideal gas.)
Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : The first ionization enthalpy for oxygen is lower than that of nitrogen.
Reason R : The four electrons in 2p orbitals of oxygen experience more electron-electron repulsion.
In the light of the above statements, choose the correct answer from the options given below.
In Friedel-Crafts alkylation of aniline, one gets
The equation
k = (6.5 1012s1)e26000K/T
is followed for the decomposition of compound A. The activation energy for the reaction is ________ kJ mol1. [nearest integer]
(Given : R = 8.314 J K1 mol1)
Consider the species CH4, NH and BH. Choose the correct option with respect to the these species.
4.0 moles of argon and 5.0 moles of PCl5 are introduced into an evacuated flask of 100 litre capacity at 610 K. The system is allowed to equilibrate. At equilibrium, the total pressure of mixture was found to be 6.0 atm. The Kp for the reaction is :
[Given : R = 0.082 L atm K1 mol1]
A white precipitate was formed when BaCl2 was added to water extract of an inorganic salt. Further, a gas 'X' with characteristic odour was released when the formed white precipitate was dissolved in dilute HCl. The anion present in the inorganic salt is
In the given reaction,

the number of sp2 hybridised carbon(s) in compound 'X' is ________.
2.2 g of nitrous oxide (N2O) gas is cooled at a constant pressure of 1 atm from 310 K to 270 K causing the compression of the gas from 217.1 mL to 167.75 mL. The change in internal energy of the process, U is 'x' J. The value of 'x' is ________. [nearest integer]
(Given : atomic mass of N = 14 g mol1 and of O = 16 g mol1. Molar heat capacity of N2O is 100 J K1 mol1)
Match List I with List II.
| List-I Ore |
List-II Composition |
||
|---|---|---|---|
| (A) | Siderite | (I) | FeCO |
| (B) | Malachite | (II) | CuCO . Cu(OH) |
| (C) | Sphalerite | (III) | ZnS |
| (D) | Calamine | (IV) | ZnCO |
Choose the correct answer from the options given below :
Amongst baking soda, caustic soda and washing soda, carbonate anion is present in :
Number of lone pair(s) of electrons on central atom and the shape BrF3 molecule respectively, are
For the reaction given below :
CoCl3 . xNH3 + AgNO3 (aq)
If two equivalents of AgCl precipitate out, then the value of x will be _____________.
The cell potential for the given cell at 298 K
Pt| H2 (g, 1 bar) | H+ (aq) || Cu2+ (aq) | Cu(s)
is 0.31 V. The pH of the acidic solution is found to be 3, whereas the concentration of Cu2+ is 10x M. The value of x is ___________.
(Given : = 0.34 V and = 0.06 V)
Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : Dacron is an example of polyester polymer.
Reason R : Dacron is made up of ethylene glycol and terephthalic acid monomers.
In the light of the above statements, choose the most appropriate answer from the options given below.
In the given reaction,

The number of electrons present in the product 'P' is _________.
Aqueous solution of which of the following boron compounds will be strongly basic in nature?
Two isomers (A) and (B) with Molar mass 184 g/mol and elemental composition C, 52.2%; H, 4.9% and Br 42.9% gave benzoic acid and p-bromobenzoic acid, respectively on oxidation with KMnO4. Isomer 'A' is optically active and gives a pale yellow precipitate when warmed with alcoholic AgNO3. Isomer 'A' and 'B' are, respectively




Sulphur dioxide is one of the components of polluted air. SO2 is also a major contributor to acid rain. The correct and complete reaction to represent acid rain caused by SO2 is :
Which of the following carbocations is most stable?




The number of chiral alcohol(s) with molecular formula C4H10O is ________.
Let y = y(x), x > 1, be the solution of the differential equation , with . If , then the value of is equal to _________.
The number of values of a N such that the variance of 3, 7, 12, a, 43 a is a natural number is :
From the base of a pole of height 20 meter, the angle of elevation of the top of a tower is 60. The pole subtends an angle 30 at the top of the tower. Then the height of the tower is :
Let M = \left[ {\matrix{ 0 & { - \alpha } \cr \alpha & 0 \cr } } \right], where is a non-zero real number an . If , then the positive integral value of is ____________.
Negation of the Boolean statement (p q) (( r) p) is equivalent to :
Let f : R R be a function defined by f(x) = (x 3)n1 (x 5)n2, n1, n2 N. Then, which of the following is NOT true?
For real numbers a, b (a > b > 0), let
Area
and
Area
Then, the value of (a b)2 is equal to ___________.
Let arg(z) represent the principal argument of the complex number z. Then, |z| = 3 and arg(z 1) arg(z + 1) = intersect :
The distance of the origin from the centroid of the triangle whose two sides have the equations and and whose orthocenter is is :
The total number of four digit numbers such that each of first three digits is divisible by the last digit, is equal to ____________.
Let be a root of the equation 1 + x2 + x4 = 0. Then, the value of 1011 + 2022 3033 is equal to :
The probability that a relation R from {x, y} to {x, y} is both symmetric and transitive, is equal to :
Let 3, 6, 9, 12, ....... upto 78 terms and 5, 9, 13, 17, ...... upto 59 terms be two series. Then, the sum of the terms common to both the series is equal to ________.
Let lie on the plane , for some p, q R. The shortest distance of the plane from the origin is :
Let the coefficients of x1 and x3 in the expansion of , be m and n respectively. If r is a positive integer such that , then the value of r is equal to __________.
Let f and g be twice differentiable even functions on (2, 2) such that , , and , . Then, the minimum number of solutions of in is equal to ________.
Let A = \left( {\matrix{ 2 & { - 1} \cr 0 & 2 \cr } } \right). If , then the sum of all elements of the matrix B is
If , then I equals
Let Q be the mirror image of the point P(1, 2, 1) with respect to the plane x + 2y + 2z = 16. Let T be a plane passing through the point Q and contains the line . Then, which of the following points lies on T?
The number of solutions of the equation in the interval (0, 10) is _________.
Let , and be a vector such that and . Then the value of is equal to _________.
If is the smallest positive integer for which are noncollinear, then the length of the median, in ABC, through A is :
Let f be a real valued continuous function on [0, 1] and .
Then, which of the following points (x, y) lies on the curve y = f(x) ?
If y = y(x) is the solution of the differential equation and y (0) = 0, then is equal to
Let a triangle ABC be inscribed in the circle such that . If the length of side AB is , then the area of the ABC is equal to :
The value of is equal to:
Let f(x) and g(x) be two real polynomials of degree 2 and 1 respectively. If and , then the value of is _________.
The sum of the infinite series is equal to :
Let P : y2 = 4ax, a > 0 be a parabola with focus S. Let the tangents to the parabola P make an angle of with the line y = 3x + 5 touch the parabola P at A and B. Then the value of a for which A, B and S are collinear is :
Let n 5 be an integer. If 9n 8n 1 = 64 and 6n 5n 1 = 25, then is equal to