Neet 2025 PYQ

Consider a water tank as shown in the figure. It has one wall at $x=L$ and is very wide in the $z$ direction. When filled with a liquid of surface tension $S$ and density $\rho$, the liquid surface makes an angle ${\theta }_0$ (${\theta }_0\ll 1$) with the $x$ -axis at $x=L$. If $y(x)$ is the height of the surface, then the equation for $y(x)$ is:(Take $\theta (x)\approx \sin \theta (x)\approx \tan \theta (x)=\frac{dy}{dx}$ and $g$ as acceleration due to gravity)

A microscope has an objective of focal length $2\text{cm}$, eyepiece of focal length $4\text{cm}$ and the tube length of $40\text{cm}$. If the distance of distinct vision of eye is $25\text{cm}$, the magnification in the microscope is:

An electron (mass $9\times 10^{-31}\text{kg}$ and charge $1.6\times 10^{-19}\text{C}$) moving with speed $c/100$ ($c$ = speed of light) is injected into a magnetic field $\vec{B}$ of magnitude $9\times 10^{-4}\text{T}$ perpendicular to its direction of motion. We wish to apply a uniform electric field $\vec{E}$ together with the magnetic field so that the electron does not deflect from its path. Then (speed of light $c=3\times 10^8{\text{ms}}^{-1}$):

There are two inclined surfaces of equal length ($L$) and same angle of inclination $45^{\circ }$ with the horizontal. One of them is rough and the other is perfectly smooth. A given body takes 2 times as much time to slide down on rough surface than on the smooth surface. The coefficient of kinetic friction (${\mu }_k$) between the object and the rough surface is close to:

The kinetic energies of two similar cars A and B are $100\text{J}$ and $225\text{J}$ respectively. On applying breaks, car A stops after $1000\text{m}$ and car B stops after $1500\text{m}$. If $F_A$ and $F_B$ are the forces applied by the breaks on cars A and B, respectively, then the ratio $F_A/F_B$ is:

The current passing through the battery in the given circuit is:

A bob of heavy mass $m$ is suspended by a light string of length $l$. The bob is given a horizontal velocity $v_0$ as shown in figure. If the string gets slack at some point $P$ making an angle $\theta$ from the horizontal, the ratio of the speed $v$ of the bob at point $P$ to its initial speed $v_0$ is:

The output ($Y$) of the given logic implementation is similar to the output of an/a _________ gate.

The electric field in a plane electromagnetic wave is given by $E_z=60\cos (5x+1.5\times 10^{9}t)\text{ V/m}$. Then expression for the corresponding magnetic field is:

A ball of mass $0.5\text{kg}$ is dropped from a height of $40\text{m}$. The ball hits the ground and rises to a height of $10\text{m}$. The impulse imparted to the ball during its collision with the ground is (Take $g=9.8{\text{m/s}}^2$):

$AB$ is a part of an electrical circuit (see figure). The potential difference $V_A-V_B$ at the instant when current $i=2\text{A}$ and is increasing at a rate of $1\text{amp / second}$ is:

A $2\text{amp}$ current is flowing through two different small circular copper coils having radii ratio $1:2$. The ratio of their respective magnetic moments will be:

In a certain camera, a combination of four similar thin convex lenses are arranged axially in contact. Then the power of the combination and the total magnification in comparison to the power ($p$) and magnification ($m$) for each lens will be, respectively:

An oxygen cylinder of volume $30\text{litre}$ has $18.20\text{moles}$ of oxygen. After some oxygen is withdrawn from the cylinder, its gauge pressure drops to $11\text{atmospheric pressure}$ at temperature $27^{\circ }\text{C}$. The mass of the oxygen withdrawn from the cylinder is nearly equal to:[Given, $R=\frac{100}{12}{\text{J mol}}^{-1}{\text{K}}^{-1}$, molecular mass of ${\text{O}}_2=32$, $1\text{atm pressure}=1.01\times 10^5{\text{N/m}}^2$ ]

In some appropriate units, time ($t$) and position ($x$) relation of a moving particle is given by $t=x^2+x$. The acceleration of the particle is:

To an ac power supply of $220\text{V}$ at $50\text{Hz}$, a resistor of $20\Omega$, a capacitor of reactance $25\Omega$ and an inductor of reactance $45\Omega$ are connected in series. The corresponding current in the circuit and the phase angle between the current and the voltage is, respectively:

The Sun rotates around its centre once in $27$ days. What will be the period of revolution if the Sun were to expand to twice its present radius without any external influence? Assume the Sun to be a sphere of uniform density.

A model for quantized motion of an electron in a uniform magnetic field $B$ states that the flux passing through the orbit of the electron is $n(h/e)$ where $n$ is an integer, $h$ is Planck's constant and $e$ is the magnitude of electron's charge. According to the model, the magnetic moment of an electron in its lowest energy state will be ($m$ is the mass of the electron):

Three identical heat conducting rods are connected in series as shown in the figure. The rods on the sides have thermal conductivity $2K$ while that in the middle has thermal conductivity $K$. The left end of the combination is maintained at temperature $3T$ and the right end at $T$. The rods are thermally insulated from outside. In steady state, temperature at the left junction is $T_1$ and that at the right junction is $T_2$. The ratio $T_1/T_2$ is:

The plates of a parallel plate capacitor are separated by $d$. Two slabs of different dielectric constant $K_1$ and $K_2$ with thickness $\frac{3}{8}d$ and $\frac{d}{2}$, respectively are inserted in the capacitor. Due to this, the capacitance becomes two times larger than when there is nothing between the plates. If $K_1=1.25K_2$, the value of $K_1$ is:

Two cities X and Y are connected by a regular bus service with a bus leaving in either direction every T min. A girl is driving scooty with a speed of $60\text{km/h}$ in the direction X to Y notices that a bus goes past her every $30\text{minutes}$ in the direction of her motion, and every $10\text{minutes}$ in the opposite direction. Choose the correct option for the period T of the bus service and the speed (assumed constant) of the buses.

A uniform rod of mass $20\text{kg}$ and length $5\text{m}$ leans against a smooth vertical wall making an angle of $60^{\circ }$ with it. The other end rests on a rough horizontal floor. The friction force that the floor exerts on the rod is (take $g=10{\text{m/s}}^2$):

In an oscillating spring-mass system, a spring is connected to a box filled with sand. As the box oscillates, sand leaks slowly out of the box vertically so that the average frequency $\omega (t)$ and average amplitude $A(t)$ of the system change with time $t$. Which one of the following options schematically depicts these changes correctly?

A balloon is made of a material of surface tension $S$ and its inflation outlet (from where gas is filled in it) has small area $A$. It is filled with a gas of density $\rho$ and takes a spherical shape of radius $R$. When the gas is allowed to flow freely out of it, its radius $r$ changes from $R$ to $0$ (zero) in time $T$. If the speed $v(r)$ of gas coming out of the balloon depends on $r$ as $r^{\alpha }$ and $T\propto S^a{A}^{\beta }{\rho }^{\gamma }{R}^{\delta }$ then:

Consider the diameter of a spherical object being measured with the help of a Vernier callipers. Suppose its $10$ Vernier Scale Divisions (V.S.D.) are equal to its $9$ Main Scale Divisions (M.S.D.). The least division in the M.S. is $0.1\text{cm}$ and the zero of V.S. is at $x=0.1\text{cm}$ when the jaws of Vernier callipers are closed.
If the main scale reading for the diameter is $M=5\text{cm}$ and the number of coinciding vernier division is $8$, the measured diameter after zero error correction, is:

A parallel plate capacitor made of circular plates is being charged such that the surface charge density on its plates is increasing at a constant rate with time. The magnetic field arising due to displacement current is:

An unpolarized light beam travelling in air is incident on a medium of refractive index $1.73$ at Brewster's angle. Then:

Two identical charged conducting spheres A and B have their centres separated by a certain distance. Charge on each sphere is $q$ and the force of repulsion between them is $F$. A third identical uncharged conducting sphere is brought in contact with sphere A first and then with B and finally removed from both. New force of repulsion between spheres A and B (Radii of A and B are negligible compared to the distance of separation so that for calculating force between them they can be considered as point charges) is best given as:

A container has two chambers of volumes $V_1=2\text{litres}$ and $V_2=3\text{litres}$ separated by a partition made of a thermal insulator. The chambers contains $n_1=5$ and $n_2=4$ moles of ideal gas at pressures $p_1=1\text{atm}$ and $p_2=2\text{atm}$, respectively. When the partition is removed, the mixture attains an equilibrium pressure of:

A particle of mass $m$ is moving around the origin with a constant force $F$ pulling it towards the origin. If Bohr model is used to describe its motion, the radius $r$ of the $n^{th}$ orbit and the particle's speed $v$ in the orbit depend on $n$ as:

The radius of Martian orbit around the Sun is about $4$ times the radius of the orbit of Mercury. The Martian year is $687$ Earth days. Then which of the following is the length of $1$ year on Mercury?

A body weighs $48\text{N}$ on the surface of the earth. The gravitational force experienced by the body due to the earth at a height equal to one-third the radius of the earth from its surface is:

A wire of resistance $R$ is cut into $8$ equal pieces. From these pieces two equivalent resistances are made by adding four of these together in parallel. Then these two sets are added in series. The net effective resistance of the combination is:

De-Broglie wavelength of an electron orbiting in the $n=2$ state of hydrogen atom is close to (Given Bohr radius $=0.052\text{nm}$):

An electric dipole with dipole moment $5\times 10^{-6}\text{Cm}$ is aligned with the direction of a uniform electric field of magnitude $4\times 10^5\text{N/C}$. The dipole is then rotated through an angle of $60^{\circ }$ with respect to the electric field. The change in the potential energy of the dipole is:

A constant voltage of $50\text{V}$ is maintained between the points A and B of the circuit shown in the figure. The current through the branch CD of the circuit is:

A photon and an electron (mass $m$) have the same energy $E$. The ratio $({\lambda }_{\text{photon}}/{\lambda }_{\text{electron}})$ of their de-Broglie wavelengths is ($c$ is the speed of light):

Which of the following options represents the variation of photoelectric current with intensity and frequency of light shown on the x-axis?

A sphere of radius $R$ is cut from a larger solid sphere of radius $2R$ as shown in the figure. The ratio of the moment of inertia of the smaller sphere to that of the rest part of the sphere about the Y-axis is:

A full wave rectifier circuit with diodes ($D_1$) and ($D_2$) is shown in the figure. If input supply voltage $V_{in}=220\sin (100\pi t)\text{volt}$, then at $t=15\text{msec}$:

Two gases A and B are filled at the same pressure in separate cylinders with movable pistons of radius $r_A$ and $r_B$, respectively. On supplying an equal amount of heat to both the systems reversibly under constant pressure, the pistons of gas A and B are displaced by $16\text{cm}$ and $9\text{cm}$, respectively. If the change in their internal energy is the same, then the ratio $r_A/r_B$ is equal to:

A physical quantity $P$ is related to four observations $a$, $b$, $c$ and $d$ as follows:
$$P=a^3{b}^2/c\sqrt{d}$$
The percentage errors of measurement in $a$, $b$, $c$ and $d$ are $1\%$, $3\%$, $2\%$ and $4\%$ respectively. The percentage error in the quantity $P$ is:

Two simple harmonic motions are represented by the equations $y_1=10\sin (3\pi t+\pi /4)$ and $y_2=5[\sin (3\pi t)+\sqrt{3}\cos (3\pi t)]$. The ratio of their amplitudes is:

The intensity of transmitted light when a polaroid sheet, placed between two crossed polaroids at $22.5^{\circ }$ from the polarization axis of one of the polaroids, is ($I_0$ is the intensity of polarised light after passing through the first polaroid):

Two identical point masses P and Q, suspended from two separate massless springs of spring constants $k_1$ and $k_2$, respectively, oscillate vertically. If their maximum speeds are the same, the ratio $(A_Q/A_P)$ of the amplitude $A_Q$ of mass $Q$ to the amplitude $A_P$ of mass $P$ is:

A pipe open at both ends has a fundamental frequency $f$ in air. The pipe is now dipped vertically in a water drum to half of its length. The fundamental frequency of the air column is now equal to:

The ratio of the wavelengths of the light absorbed by a Hydrogen atom when it undergoes $n=2\to n=3$ and $n=4\to n=6$ transitions, respectively, is:

Which of the following statements are true?A. Unlike Ga that has a very high melting point, Cs has a very low melting point.B. On Pauling scale, the electronegativity values of N and Cl are not the same.C. $Ar,K^{+},C{l}^{-},C{a}^{2+}$, and $S^{2-}$ are all isoelectronic species.D. The correct order of the first ionization enthalpies of Na, Mg, Al, and Si is Si > Al > Mg > Na.E. The atomic radius of Cs is greater than that of Li and Rb.Choose the correct answer from the options given below:

Match List I with List IIList I (Ion)A. $C{o}^{2+}$ B. $M{g}^{2+}$ C. $P{b}^{2+}$ D. $A{l}^{3+}$ List II (Group Number in Cation Analysis)I. Group-III. Group-IIIIII. Group-IVIV. Group-VIChoose the correct answer from the options given below:

Predict the major product 'P' in the following sequence of reactions:

Energy and radius of first Bohr orbit of $H{e}^{+}$ and $L{i}^{2+}$ are:[Given $R_H=2.18\times 10^{-18}\text{J},a_0=52.9\text{pm}$ ]

Which of the following are paramagnetic?A. $[NiC{l}_4{]}^{2-}$ B. $Ni(CO{)}_4$ C. $[Ni(CN{)}_4{]}^{2-}$ D. $[Ni(H_{2}O{)}_6{]}^{2+}$ E. $Ni(PP{h}_3{)}_4$ Choose the correct answer from the options given below:

Given below are two statements:Statement I: Like nitrogen that can form ammonia, arsenic can form arsine.Statement II: Antimony cannot form antimony pentoxide.In the light of the above statements, choose the most appropriate answer from the options given below:

Which among the following electronic configurations belong to main group elements?
A. [Ne]$3s^1$ B. [Ar]$3d^{3}4s^2$ C. [Kr]$4d^{10}5s^{2}5p^5$ D. [Ar]$3d^{10}4s^1$ E. [Rn]$5f^{0}6d^{2}7s^2$

Dalton's Atomic theory could not explain which of the following?

Consider the following compounds: $\underline{\text{K}}{\text{O}}_2$, ${\text{H}}_2{\underline{\text{O}}}_2$ and ${\text{H}}_2\underline{\text{S}}{\text{O}}_4$. The oxidation states of the underlined elements in them are, respectively:

If the half-life ($t_{1/2}$) for a first order reaction is $1$ minute, then the time required for $99.9\%$ completion of the reaction is closest to:

The correct order of the wavelength of light absorbed by the following complexes is,A. $[\text{Co}({\text{NH}}_3{)}_6{]}^{3+}$ B. $[\text{Co}(\text{CN}{)}_6{]}^{3-}$ C. $[\text{Cu}({\text{H}}_2\text{O}{)}_4{]}^{2+}$ D. $[\text{Ti}({\text{H}}_2\text{O}{)}_6{]}^{3+}$ Choose the correct answer from the options given below:

Which one of the following compounds can exist as cis-trans isomers?

Phosphoric acid ionizes in three steps with their ionization constant values $K_{a1}$, $K_{a2}$ and $K_{a3}$, respectively, while $K$ is the overall ionization constant. Which of the following statements are true?A. $\log K=\log K_{a1}+\log K_{a2}+\log K_{a3}$ B. ${\text{H}}_3{\text{PO}}_4$ is a stronger acid than ${\text{H}}_2{\text{PO}}_4^{-}$ and ${\text{HPO}}_4^{2-}$ C. $K_{a1}>K_{a2}>K_{a3}$ D. $K_{a1}=\frac{K_{a3}+K_{a2}}{2}$ Choose the correct answer from the options given below:

Which one of the following reactions does NOT give benzene as the product?

If the molar conductivity (${\Lambda }_m$) of a $0.050{\text{mol L}}^{-1}$ solution of a monobasic weak acid is $90{\text{S cm}}^2{\text{ mol}}^{-1}$, its extent (degree) of dissociation will be[Assume ${\lambda }_{+}^{\circ }=349.6{\text{S cm}}^2{\text{ mol}}^{-1}$ and ${\lambda }_{-}^{\circ }=50.4{\text{S cm}}^2{\text{ mol}}^{-1}$ ]

Given below are two statements:Statement I: A hypothetical diatomic molecule with bond order zero is quite stable.Statement II: As bond order increases, the bond length increases.In the light of the above statements, choose the most appropriate answer from the options given below:

Out of the following complex compounds, which of the compound will be having the minimum conductance in solution?

Match List - I with List - IIList-IA. ${\text{XeO}}_3$ B. ${\text{XeF}}_2$ C. ${\text{XeOF}}_4$ D. ${\text{XeF}}_6$ List-III. $s{p}^{3}d$; linearII. $s{p}^3$; pyramidalIII. $s{p}^3{d}^3$; distorted octahedralIV. $s{p}^3{d}^2$; square pyramidalChoose the correct answer from the options given below:

$\text{C(s)}+2{\text{H}}_2\text{(g)}\to {\text{CH}}_4\text{(g)};\Delta H=-74.8{\text{kJ mol}}^{-1}$. Which of the following diagrams gives an accurate representation of the above reaction? [$R\to$ reactants; $P\to$ products]

Match List - I with List - IIList-I (Example)A. HumidityB. AlloysC. AmalgamsD. SmokeList-II (Type of Solution)I. Solid in solidII. Liquid in gasIII. Solid in gasIV. Liquid in solidChoose the correct answer from the options given below:

The correct order of decreasing basic strength of the given amines is:

Among the following, choose the ones with equal number of atoms:A. $212\text{g}$ of ${\text{Na}}_2{\text{CO}}_3$ ($\text{s}$) [molar mass = $106\text{g}$ ]B. $248\text{g}$ of ${\text{Na}}_2\text{O}$ ($\text{s}$) [molar mass = $62\text{g}$ ]C. $240\text{g}$ of $\text{NaOH}$ ($\text{s}$) [molar mass = $40\text{g}$ ]D. $12\text{g}$ of ${\text{H}}_2$ ($\text{g}$) [molar mass = $2\text{g}$ ]E. $220\text{g}$ of ${\text{CO}}_2$ ($\text{g}$) [molar mass = $44\text{g}$ ]Choose the correct answer from the options given below:

Match List I with List II:List I (Name of Vitamin)A. Vitamin ${\text{B}}_{12}$ B. Vitamin DC. Vitamin ${\text{B}}_2$ D. Vitamin ${\text{B}}_6$ List II (Deficiency disease)I. CheilosisII. ConvulsionsIII. RicketsIV. Pernicious anaemiaChoose the correct answer from the options given below:

The correct order of decreasing acidity of the following aliphatic acids is:

Given below are two statements:Statement I: Ferromagnetism is considered as an extreme form of paramagnetism.Statement II: The number of unpaired electrons in a ${\text{Cr}}^{2+}$ ion ($Z=24$) is the same as that of a ${\text{Nd}}^{3+}$ ion ($Z=60$).In the light of the above statements, choose the correct answer from the options given below:

Match List I with List II:List I (Mixture)A. ${\text{CHCl}}_3+{\text{C}}_6{\text{H}}_5{\text{NH}}_2$ B. Crude oil in petroleum industryC. Glycerol from spent-lyeD. Aniline - waterList II (Method of Separation)I. Distillation under reduced pressureII. Steam distillationIII. Fractional distillationIV. Simple distillationChoose the correct answer from the options given below:

For the reaction $\text{A}(\text{g})\rightleftharpoons 2\text{B}(\text{g})$, the backward reaction rate constant is higher than the forward reaction rate constant by a factor of $2500$, at $1000\text{K}$.[Given : $R=0.0831{\text{L atm mol}}^{-1}{\text{K}}^{-1}$ ]$K_p$ for the reaction at $1000\text{K}$ is:

Given below are two statements:Statement I: Benzenediazonium salt is prepared by the reaction of aniline with nitrous acid at $273-278\text{K}$. It decomposes easily in the dry state.Statement II: Insertion of iodine into the benzene ring is difficult and hence iodobenzene is prepared through the reaction of benzenediazonium salt with $\text{KI}$.In the light of the above statements, choose the most appropriate answer from the options given below:

How many products (including stereoisomers) are expected from monochlorination of the following compound?

Among the given compounds I-III, the correct order of bond dissociation energy of C-H bond marked with * is:[Image showing I: iodobenzene marked at sp2 C-H; II: vinyl benzene marked at vinyl C-H; III: cyclopropane marked at ring C-H]

Which one of the following compounds does not decolourise bromine water?

Predict the major product of the following reaction:

Which of the following aqueous solutions will exhibit the highest boiling point?

Match List - I with List - II:List-IA. Haber processB. Wacker oxidationC. Wilkinson catalystD. Ziegler catalystList-III. $\text{Fe}$ catalystII. ${\text{PdCl}}_2$ III. $[({\text{PPh}}_3{)}_3\text{RhCl}]$ IV. ${\text{TiCl}}_4$ with ${\text{Al(CH}}_3{)}_3$ Choose the correct answer from the options given below:

$5$ moles of liquid X and $10$ moles of liquid Y make a solution having a vapour pressure of $70\text{torr}$. The vapour pressures of pure X and Y are $63\text{torr}$ and $78\text{torr}$ respectively. Which of the following is true regarding the described solution?

A sugar 'X' has the following properties:A. It is found in honey.B. It is a keto sugar.C. It exists in $\alpha$ and $\beta$ - anomeric forms.D. It is laevorotatory.'X' is:

Identify the suitable reagent for the following conversion:

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).Assertion (A) : 1-iodobutane undergoes ${\text{S}}_{\text{N}}2$ reaction faster than 1-chlorobutane.Reason (R) : Iodine is a better leaving group because of its large size.In the light of the above statements, choose the correct answer from the options given below :

The standard heat of formation, in $\text{kcal/mol}$ of ${\text{Ba}}^{2+}$ is :[Given : standard heat of formation of ${\text{SO}}_4^{2-}(\text{aq})=-216\text{kcal/mol}$, standard heat of crystallisation of ${\text{BaSO}}_4(\text{s})=-4.5\text{kcal/mol}$, standard heat of formation of ${\text{BaSO}}_4(\text{s})=-349\text{kcal/mol}$ ]

Total number of possible isomers (both structural as well as stereoisomers) of cyclic ethers of molecular formula ${\text{C}}_4{\text{H}}_8\text{O}$ is :

Identify the correct orders against the property mentioned:A. ${\text{H}}_2\text{O}>{\text{NH}}_3>{\text{CHCl}}_3$ – dipole momentB. ${\text{XeF}}_4>{\text{XeO}}_3>{\text{XeF}}_2$ – number of lone pairs on central atomC. $\text{O-H}>\text{C-H}>\text{N-O}$ – bond lengthD. ${\text{N}}_2>{\text{O}}_2>{\text{H}}_2$ – bond enthalpyChoose the correct answer from the options given below :