List of top Physics Questions asked in JEE Main

In figure (A), mass ‘2 m‘ is fixed on mass ‘m‘, which is attached to two springs of spring constant k. In figure (B), mass ‘m‘ is attached to two springs of spring constant ‘k‘ and ‘2k‘. If mass ‘m‘ in (A) and in (B) are displaced by distance’ x’ horizontally and then released, then time period T1 and T2 corresponding to (A) and (B) respectively follow the relation.

A charge particle is moving in a uniform magnetic field $(2 \hat{ i }+3 \hat{ j }) T$ If it has an acceleration of $(\alpha \hat{i}-4 \hat{j}) m / s ^2$, then the value of $\alpha$ will be

A 1 m long wire is broken into two unequal parts X and Y. The X part of the wire is stretched into another wire W. Length of W is twice the length of X and the resistance of W is twice that of Y. Find the ratio of length of X and Y.

An electron (mass m) with an initial velocity
$\vec{v}=v_0\hat{i}(v_0>0)$
is moving in an electric field
$\vec{E}=E_0\hat{i}(E_0>0)$
where E₀ is constant. If at t = 0 de Broglie wavelength is
$λ_0=\frac{ℎ}{mv_0}$
, then its de Broglie wavelength after time t is given by

What is the half-life period of a radioactive material if its activity drops to 1/16 th of its initial value in 30 years?

An EM wave propagating in x-direction has a wavelength of 8 mm. The electric field vibrating y-direction has maximum magnitude of 60 Vm^–1. Choose the correct equations for electric and magnetic field if the EM wave is propagating in vacuum:

A parallel beam of light of wavelength 900 nm and intensity 100 Wm^–2 is incident on a surface perpendicular to the beam. The number of photons crossing 1 cm^–2 area perpendicular to the beam in one second is

If $t = \sqrt{x} + 4$, then $\left.\frac{dx}{dt}\right|_{t=4}$ is

A parallel plate capacitor filled with a medium of dielectric constant 10, is connected across a battery and is charged. The dielectric slab is replaced by another slab of dielectric constant 15. Then the energy of capacitor will

Given below are two statements:
Statement I: A time varying electric field is a source of changing magnetic field and vice-versa. Thus a disturbance in electric or magnetic field creates EM waves.
Statement II: In a material medium, the EM wave travels with speed
$V=\frac{1}{\sqrt{µ0ε0}}$ In the light of the above statements, choose the correct answer from the options given below.

Let K₁and K₂be the maximum kinetic energies of photo-electrons emitted when two monochromatic beams of wavelength λ₁and λ₂, respectively are incident on a metallic surface. If λ₁= 3λ₂then:

A metallic conductor of length 1 m rotates in a vertical plane parallel to east-west direction about one of its end with angular velocity 5 rad s^–1. If the horizontal component of earth’s magnetic field is 0.2 × 10^–4 T, then emf induced between the two ends of the conductor is:

Given below are two statements.
Statement-I: The law of gravitation holds good for any pair of bodies in the universe.
Statement-II: The weight of any person becomes zero when the person is at the centre of the earth.
In the light of the above statements, choose the correct 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

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

Assertion A :n-p-n transistor permits more current than a p-n-p transistor.
Reason R: Electrons have greater mobility as a charge carrier.

Choose the correct answer from the options given below:

A long cylindrical volume contains a uniformly distributed charge of density ρ. The radius of cylindrical volume is R. A charge particle (q) revolves around the cylinder in a circular path. The kinetic energy of the particle is:

An aluminium wire is stretched to make its length, 0.4% larger. The percentage change in resistance is

Two masses $M_1$ and $M_2$ are tied together at the two ends of a light inextensible string that passes over a frictionless pulley. When the mass $M_2$ is twice that of $M_1$, the acceleration of the system is $a_1$. When the mass $M_2$ is thrice that of $M_1$, the acceleration of the system is $a_2$. The ratio $\frac{a_1}{a_2}$ will be

The area of cross section of the rope used to lift a load by a crane is $2.5 × 10^{–4}$ $m^2$. The maximum lifting capacity of the crane is $10$ metric tons. To increase the lifting capacity of the crane to $25$ metric tons, The required area of cross section of the rope should be

Two capacitors having capacitance C₁ and C₂ respectively are connected as shown in figure. Initially, capacitor C₁ is charged to a potential difference V volt by a battery. The battery is then removed and the charged capacitor C₁ is now connected to uncharged capacitor C₂ by closing the switch S. The amount of charge on the capacitor C₂, after equilibrium, is

Two capacitors having capacitance C1 and C2

Given below two statements: One is labelled as Assertion (A) and other is labelled as Reason (R).
Assertion (A) : Non-polar materials do not have any permanent dipole moment.
Reason (R) :When a non-polar material is placed in an electric field, the centre of the positive charge distribution of it’s individual atom or molecule coincides with the centre of the negative charge distribution.
In the light of above statements, choose the most appropriate answer from the options given below.

The magnetic flux through a coil perpendicular to its plane is varying according to the relation $\varphi = 5t^3 + 4t^2 + 2t - 5$ Weber. If the resistance of the coil is 5 ohm, then the induced current through the coil at t = 2 s will be,

If electric field intensity of a uniform plane electromagnetic wave is given as
$E = -301.6 \sin(kz - \omega t) \hat{a}_x + 452.4 \sin(k\omega - \omega t) \hat{a}_y \, \frac{V}{m}$
Then, magnetic intensity ‘H’ of this wave in Am^–1 will be :
[Given : Speed of light in vacuum c = 3 × 10⁸ms^–1, Permeability of vacuum $\mu_0 = 4\pi \times 10^{-7}$ NA^–2]

The elastic behavior of material for linear stress and linear strain, is shown in the figure. The energy density for a linear strain of 5×10^–4 is ____ kJ/m³. Assume that material is elastic up to the linear strain of 5×10^–4

An expression of energy density is given by
$u = \frac{α}{β} sin (\frac{αx}{kt})$
, where α, β are constants, x is displacement, k is Boltzmann constant and t is the temperature. The dimensions of β will be