List of top Physics Questions asked in JEE Main

A proton and an α-particle are accelerated from rest by 2V and 4V potentials, respectively. The ratio of their de-Broglie wavelength is

A 12.5 eV electron beam is used to bombard gaseous hydrogen at room temperature. The number of spectral lines emitted will be

In an n-p-n common emitter (CE) transistor the collector current changes from 5 mA to 16 mA for the change in base current from 100 μA and 200 μA, respectively. The current gain of transistor is______.

An organ pipe 40cm long is open at both ends. The speed of sound in air is 360ms^-1 . The frequency of the second harmonic is ____Hz.

An air bubble of diameter 6 mm rises steadily through a solution of density 1750kg / m³ at the rate of 0.35 cm/s. The co-efficient of viscosity of the solution (neglect density of air) is ____Pas (given, g = 10ms^-2)

The momentum of a body is increased by 50%. The percentage increase in the kinetic energy of the body is ______%

A nucleus with mass number 242 and binding energy per nucleon as 7.6 MeV breaks into fragment each with mass number 121. If each fragment nucleus has binding energy per nucleon as 8.1 MeV, the total gain in binding energy is ____MeV.

An oscillating LC circuit consists of a 75 mH inductor and a 1.2 uF capacitor. If the maximum charge to the capacitor is 2.7μC. The maximum current in the circuit will be _____mA.

The magnetic intensity at the centre of a long current carrying solenoid is found to be 1.6 x 10³ Am^-1. If the number of turns is 8 per cm, then the current flowing through the solenoid is_____A.

A current of 2 A flows through a wire of crosssectional area 25.0 mm2 . The number of free electrons in a cubic meter are 2.0 x 10²⁸ . The drift velocity of the electrons is _____ x 10^-6 ms^-1 (Given, charge on electron = 1.6 x 10^-19C)

An electric dipole of dipole moment is 6.0 x 10^-6 Cm placed in a uniform electric field of 1.5 x 10³ NC^-1 in such a way that dipole moment is along electric field. The work done in rotating dipole by 180º in this field will be _____mJ.

A body is dropped on ground from a height ‘h₁’ and after hitting the ground, it rebounds to a height ‘h₂’ If the ratio of velocities of the body just before and after hitting ground is \(4\). then percentage loss in kinetic energy of the body is\(\frac{x}{4}\). The value of x is_____.

A metal block of mass m is suspended from a rigid support through a metal wire of diameter 14 mm. The tensile stress developed in the wire under equilibrium state is 7× 10⁵ Nm^-2 . The value of mass m is ___ kg. (Take, g = 9.8 ms-2 and π =\(\frac{ 22}{7}\))

Two concentric circular coils with radii 1 cm and 1000 cm, and number of turns 10 and 200 respectively are placed coaxially with centers coinciding. The mutual inductance of this arrangement will be _____× 10^-8 H.
(Take, π² = 10)

A beam of light consisting of two wavelengths 7000 Å and 5500 Å is used to obtain interference pattern in Young's double slit experiment. The distance between the slits is 2.5 mm and the distance between the plane of slits and the screen is 150 cm. The least distance from the central fringe, where the bright fringes due to both the wavelengths coincide, is n × 10^-5 m. The value of n is_____.

Experimentally it is found that 12.8 eV energy is required to separate a hydrogen atom into a proton and an electron. So the orbital radius of the electron in a hydrogen atom is\(\frac{ 9}{x} x 10^{-10}\)m. The value of the x is _____.
(1eV = 1.6 x 10^-19J, \(\frac{1}{4π∈_0}\) = 9 x 10⁹ NM² / C² and electronic charge = 1.6 x 10^-19JC)

As shown in the figure, the voltmeter reads 2V across 5Ω resistor. The resistance of the voltmeter is_____Ω.

As shown in the figure, two parallel plate capacitors having equal plate area of 200 cm2 are joined in such a way that a ≠ b. The equivalent capacitance of the combination is x ∈0 F. The value of x is_____.

A simple pendulum with length 100 cm and bob of mass 250 g is executing S.H.M. of amplitude 10cm. The maximum tension in the string is found to be \(\frac{x}{40}\) N. The value of x is___.

radius of 2^nd orbit of He⁺ of Bohr's model is r₁ and that of fourth orbit of Be³⁺ is represented as r₂. Now the ratio\(\frac{ r_2}{r_1} \)is x: 1. The value of x is___.

A fish rising vertically upward with a uniform velocity of 8 ms^-1, observes that a bird is diving vertically downward towards the fish with the velocity of 12 ms^-1. If the refractive index of water is \(\frac{4}{3}\) , then the actual velocity of the diving bird to pick the fish, will be _______ ms^-1

A thin infinite sheet charge and an infinite line charge of respective charge densities +σ and +λ are placed parallel at 5 m distance from each other. Points ‘P’ and ‘Q’ are at \(\frac{3}{π} \)m and \(\frac{4}{π}\) m perpendicular distance from line charge towards sheet charge, respectively. ‘E_P’ and ‘E_Q’ are the magnitudes of resultant electric field intensities at point ‘P’ and ‘Q’, respectively. If \(\frac{E_p}{E_Q} =\frac{ 4}{a}\) for 2|σ| = |λ|. Then the value of a is _______.

The elastic potential energy stored in a steel wire of length 20 m stretched through 2 cm is 80 J. The cross sectional area of the wire is______ mm² . (Given, y = 2.0 x 10¹¹ Nm^-2)

A solid sphere is rolling on a horizontal plane without slipping. If the ratio of angular momentum about axis of rotation of the sphere to the total energy of moving sphere is π : 22 then, the value of its angular speed will be ______ rad/s.