List of top Physics Questions asked in JEE Main

A body of mass 10 kg is projected at an angle of 45° with the horizontal. The trajectory of the body is observed to pass through a point (20, 10). If T is the time of flight, then its momentum vector, at time t = T/√2, is _________.
[Take g = 10m/s2]

One mole of a monoatomic gas is mixed with three moles of a diatomic gas. The molecular specific heat of mixture at constant volume is \(\frac{\alpha^2}{4}\) RJ/mol k; then the value of α will be _______.
(Assume that the given diatomic gas has no vibrational mode).
Two light beams of intensities 4I and 9I interfere on a screen. The phase difference between these beams on the screen at point A is zero and at point B is π. The difference of resultant intensities, at the point A and B, will be_______I.
The X–Y plane be taken as the boundary between two transparent media M1 and M2.M1 in Z 0 has a refractive index of \(\sqrt2\) and M2 with \(Z<0\) has a refractive index of \(\sqrt3\). A ray of light travelling in M1 along the direction given by the vector \(\mathbf{\overrightarrow{P}} = 4\sqrt{3}\mathbf{\hat{i}} - 3\sqrt{3}\mathbf{\hat{j}} - 5\hat{k}\), is incident on the plane of separation. The value of difference between the angle of incident in M1 and the angle of refraction in M2 will be ______ degree.
If the potential barrier across a p–n junction is 0.6 V. Then the electric field intensity, in the depletion region having the width of 6×10–6 m, will be ______× 105 N/C.

Match List I with List II.

List IList II  
A.TorqueI.Nms–1
B.StressII.Jkg–1
C.Latent HeatIII.Nm
D.PowerIVNm–2

Choose the correct 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: Alloys such as constantan and manganin are used in making standard resistance coils.
Reason R: Constantan and manganin have very small value of temperature coefficient of resistance.
In the light of the above statements, choose the correct answer from the options given below.
A juggler throws balls vertically upwards with same initial velocity in air. When the first ball reaches its highest position, he throws the next ball. Assuming the juggler throws n balls per second, the maximum height the balls can reach is
A freshly prepared radioactive source of half life 2 hours 30 minutes emits radiation which is 64 times the permissible safe level. The minimum time, after which it would be possible to work safely with source, will be _______ hours.
The frequencies at which the current amplitude in an LCR series circuit becomes \(\frac{1}{2}\) times its maximum value, are 212 rad s–1 and 232 rad s–1. The resistance value in the Question: the circuit is R = 5 Ω. The self-inductance in the circuit is _____ mH.
Two identical metallic spheres A and B when placed at certain distance in air repel each other with a force of F. Another identical uncharged sphere C is first placed in contact with A and then in contact with B and finally placed at midpoint between spheres A and B. The force experienced by sphere C will be
A circuit element X when connected to an a.c. supply of peak voltage 100 V gives a peak current of 5 A which is in phase with the voltage. A second element Y when connected to the same a.c. supply also gives the same value of peak current which lags behind the voltage by \(\frac{π}{2}\). If X and Y are connected in series to the same supply, what will be the rms value of the current in ampere?
An α particle and a proton are accelerated from rest through the same potential difference. The ratio of linear momenta acquired by above two particles will be:
Read the following statements:
(A) Volume of the nucleus is directly proportional to the mass number.
(B) Volume of the nucleus is independent of mass number.
(C) Density of the nucleus is directly proportional to the mass number.
(D) Density of the nucleus is directly proportional to the cube root of the mass number.
(E) Density of the nucleus is independent of the mass number.
Choose the correct option from the following options

A liquid of density 750 kgm–3 flows smoothly through a horizontal pipe that tapers in
cross-sectional area from A1 = 1.2 × 10–2 m2 to
\(A_2=\frac{A_1}{2}\)
. The pressure difference between the wide and narrow sections of the pipe is 4500 Pa. The rate of flow of liquid is _____ × 10–3 m3s–1.

A ball is released from a height h. If t1 and t2 be the time required to complete first half and second half of the distance respectively. Then, choose the correct relation between t1 and t2..
As shown in the figure, a potentiometer wire of resistance 20 Ω and length 300 cm is connected with resistance box (R.B.) and a standard cell of emf 4 V. For a resistance ‘R‘ of resistance box introduced into the circuit, the null point for a cell of 20 mV is found to be 60 cm. The value of ‘R ‘ is Ω.
a potentiometer wire of resistance 20 Ω
If momentum of a body is increased by 20%, then its kinetic energy increases by
Two electric dipoles of dipole moments 1.2 × 10–30 C-m and 2.4 × 10–30 C-m are placed in two different uniform electric fields of strength 5 × 104 NC–1 and 15 × 104 NC–1 respectively. The ratio of maximum torque experienced by the electric dipoles will be 1:x. The value of x is _______
The diameter of an air bubble which was initially 2 mm, rises steadily through a solution of density 1750 kg m–3 at the rate of 0.35 cms–1. The coefficient of viscosity of the solution is _______ poise (in nearest integer). (The density of air is negligible).

The torque of a force \(5\^{i}+3\^{j}−7\^{k}\) about the origin is τ. If the force acts on a particle whose position vector is\( 2\^{i}+2\^{j}+\^{k}\), then the value of τ will be

A block of mass ‘m’ (as shown in figure) moving with kinetic energy E compresses a spring through a distance 25 cm when its speed is halved. The value of spring constant of used spring will be nE Nm–1 for n = _______.
A block of mass ‘m’
The metallic bob of simple pendulum has the relative density 5. The time period of this pendulum is 10 s. If the metallic bob is immersed in water, then the new time period becomes 5√x s. The value of x will be _____.
Two radioactive materials A and B have decay constants 25λ and 16λ respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of B to that of A will be ‘e’ after a time \(\frac{1}{(aλ)}\). The value of a is _____.
The root mean square speed of smoke particles of mass 5 × 10-17 in their Brownian motion in air at NTP is approximately. [Given k = 1.38 × 10-23 JK-1]