NTA JEE Main 2025 April 7th Shift 2 - Physics

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : The outer body of an air craft is made of metal which protects persons sitting inside from lightning-strikes.
Reason (R) : The electric field inside the cavity enclosed by a conductor is zero.
In the light of the above statements, choose the most appropriate answer from the options given below :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : The density of the copper $$\left(^{64}_{29}Cu\right)$$ nucleus is greater than that of the carbon $$\left(^{12}_{6}C\right)$$ nucleus.
Reason (R) : The nucleus of mass number A has a radius proportional to $$A^{1/3}$$.
In the light of the above statements, choose the most appropriate answer from the options given below :

The unit of $$\sqrt{\frac{2I}{\epsilon_0 c}}$$ is : (I = intensity of an electromagnetic wave, c : speed of light)

The dimension of $$\sqrt{\frac{\mu_0}{\epsilon_0}}$$ is equal to that of : ($$\mu_0$$ = Vacuum permeability and $$\epsilon_0$$ = Vacuum permittivity)

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : The radius vector from the Sun to a planet sweeps out equal areas in equal intervals of time and thus areal velocity of planet is constant.
Reason (R) : For a central force field the angular momentum is a constant.
In the light of about statement, Choose the most appropriate answer  from the option  given below : 

The helium and argon are put in the flask at the same room temperature (300 K). The ratio of average kinetic energies (per molecule) of helium and argon is : (Molar mass of helium = 4 g/mol, Molar mass of argon = 40 g/mol)

A capillary tube of radius 0.1 mm is partly dipped in water (surface tension 70 dyn/cm and glass water contact angle $$\simeq 0^\circ$$) with $$30^\circ$$ inclined with vertical. The length of water risen in the capillary is _____ cm. (Take $$g = 9.8$$ m/s$$^2$$)

A mirror is used to produce an image with magnification of $$\frac{1}{4}$$. If the distance between object and its image is 40 cm, then the focal length of the mirror is :

A dipole with two electric charges of 2 $$\mu$$C magnitude each, with separation distance 0.5 $$\mu$$m, is placed between the plates of a capacitor such that its axis is parallel to an electric field established between the plates when a potential difference of 5 V is applied. Separation between the plates is 0.5 mm. If the dipole is rotated by 30° from the axis, the value of the torque is :

Consider the following logic circuit. The output is Y = 0 when :

Match List-I with List-II.

Choose the correct answer from the options given below :

The equation of a wave travelling on a string is $$y = \sin[20\pi x + 10\pi t]$$, where x and t are in SI units. The minimum distance between two points having the same oscillating speed is :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason(R).
Assertion (A) : Refractive index of glass is higher than that of air.
Reason (R) : Optical density of a medium is directly proportionate to its mass density which results in a proportionate refractive index.
In the light of the above statements, choose the most appropriate answer from the options given below :

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason(R).
Assertion (A) : Magnetic monopoles do not exist.
Reason (R) : Magnetic field lines are continuous and form closed loops.
In the light of the above statements, choose the most appropriate answer from the options given below :

Which one of the following forces cannot be expressed in terms of potential energy?

Match List-I with List-II.

Choose the correct answer from the options given below :

A helicopter flying horizontally with a speed of 360 km/h at an altitude of 2 km, drops an object at an instant. The object hits the ground at  a point O, 20 s after it is dropped. Displacement of 'O' from the position of helicopter where the object was released is :
(use acceleration due to gravity $$g = 10$$ m/s$$^2$$and neglect air resistance)

An object with mass 500 g moves along x-axis with speed $$v = 4\sqrt{x}$$ m/s. The force acting on the object is :

A transparent block A having refractive index $$\mu = 1.25$$ is surrounded by another medium of refractive index $$\mu = 1.0$$. A light ray is incident on the flat face of the block with incident angle $$\theta$$. What is the maximum value of $$\theta$$ for which light suffers total internal reflection at the top surface of the block?

A parallel plate capacitor has charge $$5 \times 10^{-6}$$ C. A dielectric slab is inserted between the plates and almost fills the space between the plates. If the induced charge on one face of the slab is $$4 \times 10^{-6}$$ C then the dielectric constant of the slab is _____.

An inductor of reactance 100 $$\Omega$$, a capacitor of reactance 50 $$\Omega$$, and a resistor of resistance 50 $$\Omega$$ are connected in series with an AC source of 10 V, 50 Hz. Average power dissipated by the circuit is _____ W.

Two cylindrical rods A and B made of different materials, are joined in a straight line. The ratio of lengths, radii and thermal conductivities are: $$\frac{L_A}{L_B} = \frac{1}{2}$$, $$\frac{r_A}{r_B} = 2$$ and $$\frac{K_A}{K_B} = \frac{1}{2}$$. The free ends of rods A and B are maintained at 400 K, 200 K respectively. The temperature of rods interface is _____ K,when equilibrium is established.

The electric field in a region is given by $$\vec{E} = (2\hat{i} + 4\hat{j} + 6\hat{k}) \times 10^3$$ N/C. The flux of the field through a rectangular surface parallel to x-z plane is 6.0 Nm$$^2$$C$$^{-1}$$. The area of the surface is _____ cm$$^2$$.

M and R be the mass and radius of a disc. A small disc of radius R/3 is removed from the bigger disc. The moment of inertia of remaining part about an axis AB passing through the centre O and perpendicular to the plane of the disc is $$\frac{4}{x}MR^2$$. The value of x is _____.

A photo-emissive substance is illuminated with a radiation of wavelength $$\lambda_i$$ so that it releases electrons with de-Broglie wavelength $$\lambda_e$$. The longest wavelength of radiation that can emit photoelectron is $$\lambda_0$$. Expression for de-Broglie wavelength is given by : (m : mass of the electron, h : Planck's constant and c : speed of light)