RE-NEET Physics Class 11 Questions

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 Cₚ/Cᵥ of the gas is 8/7, then the value of f 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 4th Vernier division coincides with a division of the main scale. If this Vernier calliper measures the length of a wire to be 1 cm, the actual length of the wire is:

Consider a spring-mass simple harmonic oscillator in one dimension. The mass of the particle is m kg and the spring constant is k Nm⁻¹. At a given instant, the extension of the spring is x meter and the speed of the particle is v m s⁻¹. On the x - v plane, if the graph of v as a function of x is a circle, then the correct option is:

A frictionless circular wire of unit radius is fixed on the horizontal plane. Two point particles of unit mass start moving simultaneously from point A (θ = π/2) with identical uniform angular speeds in opposite directions, and meet again at point B (θ = −π/2). During this time, which of the following figures schematically represent the magnitude of the total linear momentum P of the system, as a function of θ?

Consider that σₛ, k_B, b represent Stefan-Boltzmann constant, Boltzmann constant and Wien’s displacement law constant, respectively. The dimension of σₛk_B⁻¹b is :

For sound waves, if the number of nodes for the 5th harmonic of an open-ended pipe is n and that for the 9th harmonic of the same pipe with one of its ends closed is m, the ratio n/m is :

Two planets P₁ and P₂ with equal mass have radii R₁ and R₂, respectively, where R₂ = $\frac{R_{1}}{2}$. The escape speeds of P₁ and P₂ are v₁ and v₂, respectively. Then $\frac{v_{2}}{v_{1}}$ is:

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 θ. If the car travels at a speed 10 m/s, then the wear and tear on its tyres is minimum. Taking the acceleration due to gravity to be 10 m/s², the value of θ is:

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 $\alpha = 1$ m/s², $\beta = 6$ m/s and $\gamma = 5$ m. The average speed of the particle, in m/s, from t = 0 to t = 6 is:

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 ball (σ) to density of the liquid (ρ), is best represented by:

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 μₖ(x) = μ₀ - αx, where μ₀, α are constants of appropriate dimensions, so that μₖ(L) = 0. The total work done by the frictional force during the motion is ημ₀MgL, where g is the acceleration due to gravity. The value of η is:

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

A solid sphere A of radius R and mass M is attached at a point to a smaller solid sphere B of radius r < R and mass m < M. Assume that the line joining their centres lies along the horizontal. The moment of inertia of the system calculated about a vertical axis passing through the centre of A is Iₐ and that calculated about a vertical axis passing through the centre of B is Iᵦ. The difference Iₐ - Iᵦ is:

Bob B of mass m at rest is hanging vertically from the ceiling via a massless string of length 10 m, as shown in the figure. Point mass A of mass m travelling horizontally with speed 10 ms⁻¹ hits bob B elastically. The bob B rises h meter after the collision. Taking the acceleration due to gravity g = 10 ms⁻² and neglecting the size of the bob, the value of h is:

A cylindrical cork of uniform density floats in a liquid of density ρ₁. 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 ρ₂, then the similar oscillation has time period 2T. The value of ρ₂/ρ₁ 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 nₐ and n_B, respectively, then the correct option is:

The temperature of a metallic sphere of radius R is increased by a small amount ΔT. If the linear coefficient of thermal expansion of the metal is α, the approximate increase in the volume of the sphere is:

In an adiabatic expansion, the temperature of one mole of an ideal monatomic gas (γ=5/3) decreases from 60K to 50K. The work done by the gas in the process is : (Take the universal gas constant as R=8.3 J mol⁻¹ K⁻¹)

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 Nm⁻². The area of cross-section at P and Q are 40 cm² and 20 cm², respectively. The rate of flow of water through the pipe, in cm³s⁻¹, is : [Take density of water=1000 kg m⁻³]

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 OB = 2 × OA. The value of L_A/L_B is:

A protein undergoes reversible thermal denaturation from its initial state N to denatured state D according to N ⇌ D. At 60 °C, the concentrations of both N and D are equal at equilibrium, and the standard enthalpy change of denaturation is 666 kJ mol⁻¹. The standard entropy change (ΔS° in kJ K⁻¹mol⁻¹) of the protein upon denaturation at 60 °C is closest to

Consider the reversible processes for 1.0 mol of an ideal gas as shown in the figure. w₁, w₂, w₃ and w₄ represent work done (in calories) in the processes 1, 2, 3 and 4, respectively; ΔU₂ and ΔU₄ are changes in the internal energy for the processes 2 and 4, respectively. [use R = 2 cal K⁻¹ mol⁻¹] The correct option is

Two moles of an ideal gas undergo free expansion from 10 L to 100 L at 300 K. The values of ΔS_system and ΔS_surroundings are (R is universal gas constant)

A bob is whirled in a horizontal circle by means of a string at an initial speed of 10 rpm. If the tension in the string is quadrupled while keeping the radius constant, the new speed is:

An ideal fluid is flowing in a non-uniform cross-sectional tube XY (as shown in the figure) from end X to end Y. If K₁ and K₂ are the kinetic energy per unit volume of the fluid at X and Y respectively, then the correct option is :

The escape velocity for earth is $v$. A planet having 9 times mass that of earth and radius, 16 times that of earth, has the escape velocity of:

An object moving along horizontal x-direction with kinetic energy 10 J is displaced through x = (3î) m by the force F⃗ = (−2î + 3ĵ) N. The kinetic energy of the object at the end of the displacement x is

An object falls from a height of 10 m above the ground. After striking the ground it loses 50% of its kinetic energy. The height upto which the object can rebounce from the ground is:

A particle is moving along x-axis with its position (x) varying with time (t) as x = αt⁴ + βt² + γt + δ. The ratio of its initial velocity to its initial acceleration, respectively, is:

The radius of gyration of a solid sphere of mass 5 kg about XY is 5 m as shown in figure. The radius of the sphere $\frac{5x}{\sqrt{7}}$ m, then the value of x is:

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Houses made of concrete roofs overlaid with foam keep the room hotter during summer.

Reason R: The layer of foam insulation prohibits heat transfer, as it contains air pockets.

In the light of the above statements, choose the correct answer from the options given below.

A particle executing simple harmonic motion with amplitude A has the same potential and kinetic energies at the displacement

Water is used as a coolant in a nuclear reactor because of its

The pitch of an error free screw gauge is 1 mm and there are 100 divisions on the circular scale. While measuring the diameter of a thick wire, the pitch scale reads 1 mm and $63^{rd}$ division on the circular scale coincides with the reference line. The diameter of the wire is:

The equilibrium state of a thermodynamic system is described by

A. Pressure

B. Total heat

C. Temperature

D. Volume

E. Work done Choose the most appropriate answer from the options given below.

A box of mass 5 kg is pulled by a cord, up along a frictionless plane inclined at 30° with the horizontal. The tension in the cord is 30 N. The acceleration of the box is (Take g = 10 m s⁻²)

The displacement of a travelling wave y = C sin(2π/λ (at − x)) where t is time, x is distance and λ is the wavelength, all in S.I. units. Then the frequency of the wave is:

An object of mass 100 kg falls from point A to B as shown in figure. The change in its weight, corrected to the nearest integer is (Rₑ is the radius of the earth):

The potential energy of a particle moving along x-direction varies as V = $\frac{Ax^2}{\sqrt{x} + B}$. The dimensions of $\frac{A^2}{B}$ are:

The two-dimensional motion of a particle, described by $\vec{r} = (\hat{i} + 2\hat{j}) A \cos t$ is a/an:

Let ω₁, ω₂ and ω₃ be the angular speed of the second hand, minute hand and hour hand of a smoothly running analog clock, respectively. If x₁, x₂ and x₃ are their respective angular distances in 1 minute then the factor which remains constant (k) is

According to the law of equipartition of energy, the number of vibrational modes of a polyatomic gas of constant γ = Cₚ/Cᵥ is (Cₚ where Cᵥ are the specific heat capacities of the gas at constant pressure and constant volume, respectively):

Choose the correct statement for the work done in the expansion and heat absorbed or released when 5 litres of an ideal gas at 10 atmospheric pressure isothermally expands into vacuum until volume is 15 litres:

For an endothermic reaction: (A) qₚ is negative. (B) ΔH is positive. (C) ΔH is negative. (D) qₚ is positive. Choose the correct answer from the options given, below: