RE-NEET 2026

An electromagnetic wave travelling in a lossless dielectric medium having a dielectric constant, $\varepsilon_r=9$, has the electric field, $E_x=E_0 \sin \left(k z-2 \pi \times 10^6 t\right) \vee m^{-1}$ where $E_0$ is the amplitude and $k$...

Consider a fixed uniformly charged insulating sphere with radius $R$ and total charge $+Q$. A point charge $-q$ ( $q \ll Q$ ) with mass $m$ is released from rest at a distance of $3 R$ from the centre of the charged sphere. When the point c...

A point charge $Q$ is placed inside a cavity within a solid isolated conducting sphere. Consider points $A, B$ and $C$ as shown in the figure, where the magnitudes of the electric fields are $E_A, E_B, E_C$, respectively. The points $B$ and...

A unit positive point charge is taken slowly through an infinitesimally thin tube that is inside a charged dielectric sphere of radius $R$, having uniform positive charge density $\rho$, as shown in the figure. The initial and final positio...

Consider three media $P, Q$ and $R$ with refractive indices $1,1.25$, and 1.5 respectively. The medium $Q$ having a thickness of 5 cm is placed between extended media $P$ and $R$ as shown in the figure. An object $O$ is placed at the centre...

Which of the following measurements require 'index correction'?

The lens combination as shown in the figure, consists of two lenses, $L_1$ and $L_2$, of the focal lengths +10 cm and -10 cm , respectively. The position of the image formed is:

Two planets $P_1$ and $P_2$ with equal mass have radii $R_1$ and $R_2$, respectively, where $R_2=\frac{R_1}{2}$. The escape speeds of $P_1$ and $P_2$ are $v_1$ and $v_2$, respectively. Then $\frac{v_2}{v_1}$ is:

In a solar system, the time-period of revolution of a planet tracing a circular orbit of radius $R$ is proportional to:

The temperature of a metallic sphere of radius $R$ is increased by a small amount $\Delta T$. If the linear coefficient of thermal expansion of the metal is $\alpha$, the approximate increase in the volume of the sphere is:

In an adiabatic expansion, the temperature of one mole of an ideal monatomic gas ( $\gamma=5 / 3$ ) decreases from 60 K to 50 K . The work done by the gas in the process is:
(Take the universal gas constant as $R=8.3 \mathrm{~J} \mathrm{~mo...

An ideal gas is made of polyatomic molecules. Each of the molecules has three translational, three rotational and $f$ number of vibrational modes. If the ratio of heat capacities $C_P / C_V$ of the gas is $8 / 7$, then the value of $f$ is:

The mean free path of molecules in an ideal gas $A$ is half that of another ideal gas $B$. The diameter of the spherical molecules of gas $A$ is twice the diameter of the molecules of $B$. If number densities of the gases $A$ and $B$ are $n...

One mole of an ideal monatomic gas undergoes a cyclic process as shown in the figure. The total heat supplied to the gas is:

A car travels on a circular racetrack of radius 50 m , which is banked at an angle $\theta$. If the car travels at a speed $10 \mathrm{~ms}^{-1}$, then the wear and tear on its tyres is minimum. Taking the acceleration due to gravity to be ...

Consider a particle moving along a straight line, whose position as a function of time is given by $s(t)=\alpha t^2-\beta t +\gamma$, where $\alpha=1 \mathrm{~ms}^{-2}, \beta=6 \mathrm{~ms}^{-1}$ and $\gamma=5 \mathrm{~m}$. The average spee...

A current $l_0$ flows through a metallic circular loop of radius $r$ as shown in the figure. Resistance of the segment $A B C$ is half that of $A D C$. Magnitude of magnetic field at the centre $O$ of the loop is :

Two infinitely long parallel conducting wires $A$ and $B$ carry currents $I$ and $2 I$, respectively, in the same direction. The wire $A$ has uniform mass per unit length $\lambda$ and lies on an insulated floor. The wire $B$ is kept fixed ...

A cylindrical cork of uniform density floats in a liquid of density $\rho_1$. If the cork is depressed slightly and released, it oscillates harmonically with time period $T$. If the same cork floats in another liquid of density $\rho_2$, th...

Consider a spring-mass simple harmonic oscillator in one dimension. The mass of the particle is $m \mathrm{~kg}$ and the spring constant is $k \mathrm{Nm}^{-1}$. At a given instant, the extension of the spring is $x$-meter and the speed of ...

In the measurement of viscosity of liquids using terminal velocity experiment, spherical balls of same radius but having different densities are used. The variation of the terminal velocity ( $v$ ) with the ratio of density of spherical bal...

Water flows in a streamline motion through a horizontal pipe of circular cross-section as shown in the figure. The pressure difference of water between $P$ and $Q$ is $15 \mathrm{Nm}^{-2}$. The area of cross-section at $P$ and $Q$ are $40 \...

A thin horizontal disc is rotating about a vertical axis passing through its fixed centre $O$. Its angular momentum is $L_A$ and $L_B$ computed about points $A$ and $B$, respectively, with $O B=2 \times O A$. The value of $\frac{L_A}{L_B}$ ...

A solid sphere $A$ of radius $R$ and mass $M$ is attached at a point to a smaller solid sphere $B$ of radius $r

An ideal Zener diode with breakdown voltage of -3 V is reverse biased with a negative input voltage $V_i=-5 \mathrm{~V}$. The magnitude of voltage difference between point $B$ and $A$ is:

Three identical p-n junction diodes $D_1, D_2$, and $D_3$ are connected across a battery as shown in the figure. If the width of the depletion regions of $D_1, D_2$ and $D_3$ are $W_1, W_2$ and $W_3$, respectively, then the correct option i...

Consider that $\sigma_s, k_B, b$ represents Stefan-Boltzmann constant, Boltzmann constant and Wien's displacement law constant, respectively. The dimension of $\sigma_s k_B^{-1} b$ is

One main scale division of a Vernier calliper is equal to 1 mm and the number of divisions on the Vernier scale is 10 . When both the jaws touch each other, the Vernier scale shifts to the left of zero of the main scale in such a way that $...

For sound waves, if the number of nodes for the $5^{\text {th }}$ harmonic of an open-ended pipe is $n$ and that for the $9^{\text {th }}$ harmonic of the same pipe with one of its ends closed is $m$, the ratio $\frac{n}{m}$ is

A particle of mass $M$ moves along a horizontal $x$ axis from $x=0$ to $x=L$. The coefficient of kinetic friction varies as a function of $x$ as $\mu_k(x)=\mu_0-\alpha x$, where $\mu_0$, $\alpha$ are constants of appropriate dimensions, so ...