List of top Questions asked in JEE Main

A thermodynamic system is taken from an original state A to an intermediate state B by a linear process as shown in the figure. It's volume is then reduced to the original value from B to C by an isobaric process. The total work done by the gas from A to B and B to C would be :

Assertion: The angular velocity of the moon revolving around the earth is more than that of the earth revolving around the Sun.
Reason: The time taken by the moon to revolve around the earth is less than the time taken by the earth to revolve around the sun.

In a given circuit, an ideal battery is connected with four resistances as shown. Find current \(i\) as mentioned in the diagram.

An artillery of mass \(M_1\), fires a shell of mass \(M_2\). At the time of firing the ratio of kinetic energy is.

A LCR circuit is at resonance for a capacitor C, inductance L and resistance R. Now the value of resistance is halved keeping all other parameters same. The current amplitude at resonance will be now:

If the ratio of centripetal acceleration of two particles moving on the same circular path is \(3: 4\). Find the ratio of their speed.

A wire of resistance \( R \) and length \( L \) is cut into 5 equal parts. If these parts are joined in parallel, then the resultant resistance will be:

At which temperature the r.m.s. velocity of a hydrogen molecule equal to that of an oxygen molecule at 47ºC?

UV light of 4.13 eV is incident on a photosensitive metal surface having work function 3.13 eV. The maximum kinetic energy of ejected photoelectrons will be

A coil is placed perpendicular to a magnetic field of 5000 T. When the field is changed to 3000 T in 2s, an induced emf of 22 V is produced in the coil. If the diameter of the coil is 0.02 m, then the number of turns in the coil is :

Assuming the earth to be a sphere of uniform mass density, a body weighed 300 N on the surface of earth. How much it would weigh at R/4 depth under surface of earth ?

A particle of mass m moves on a straight line with its velocity increasing with distance according to the equation \( v = \alpha \sqrt{x} \), where \(\alpha\) is a constant. The total work done by all the forces applied on the particle during its displacement from \( x = 0 \) to \( x = d \), will be:

De Broglie wavelength of proton = \(λ\) and that of an a particle \(2λ\). The ratio of velocity of proton to that of \(\alpha\) particle is 

In the figure shown, find the ratio of tensions in the strings, \(\frac{T_1}{T_2}\)

To find the spring constant (k) of a spring experimentally, a student commits 2% positive error in the measurement of time and 1% negative error in measurement of mass. The percentage error in determining value of k is :

Two charged particles A and B have charge q each while masses are \(m_1\) & \(m_2\). Both have the same velocity v and enter into a transverse magnetic field B such that their radii are \(r_1\) & \(r_2\). Then the ratio \(m_1 : m_2\) is

In a nuclear fission reaction of an isotope of mass \( M \), three similar daughter nuclei of the same mass are formed. The speed of a daughter nuclei in terms of mass defect \( \Delta M \) will be:

Two forces \(F_1\) and \(F_2\) are applied on two rods \(P\) and \(Q\) of same materials such that elongation in rods are same. If ratio of their radii is \(x : y\) and ratio of length is \(m : n\), then ratio of \(F_1 : F_2\) is

In a simple pendulum of length 10 m, the string is initially kept horizontal and the bob is released. 10% of energy is lost till the bob reaches the lowest position. Then find the speed of the bob at the lowest position.

\(\sigma\) is the uniform surface charge density of a thin spherical shell of radius \(R\). The electric field at any point on the surface of the spherical shell is:

Ice at temperature –10°C is converted to steam at 100°C, the curve plotted between temperature (T) and time (t) when it is being heated by constant power source is

In a metre-bridge, when a resistance of $2 \, \Omega$ is in the left gap and the unknown resistance in the right gap, the balance length is found to be 40 cm. On shunting the unknown resistance with $2 \, \Omega$, the balance length changes by:

A particle moves in the x-y plane under the influence of a force \( \vec{F} \) such that its linear momentum is \[ \vec{P}(t) = \hat{i} \cos(kt) - \hat{j} \sin(kt). \] If \( k \) is constant, the angle between \( \vec{F} \) and \( \vec{P} \) will be:

For the thin convex lens, the radii of curvature are at 15 cm and 30 cm respectively. The focal length the lens is 20 cm. The refractive index of the material is :

A 1 kg mass is suspended from the ceiling by a rope of length 4m. A horizontal force 'F' is applied at the mid point of the rope so that the rope makes an angle of 45° with respect to the vertical axis as shown in figure. The magnitude of F is