List of top Questions asked in WBJEE

A body of mass $m$ is thrown with velocity $u$ from the origin of a coordinate axes at an angle with the horizon. The magnitude of the angular momentum of the particle about the origin at time $t$ when it is at the maximum height of the trajectory is proportional to
A particle is moving in the $x$-$y$ plane according to $r = b \cos \omega t \hat{i} + b \sin \omega t \hat{j}$. Where $\omega$ is constant. Which of the following statement(s) is/are true?
An electron revolves around the nucleus in a circular path with angular momentum $L$. A uniform magnetic field $B$ is applied perpendicular to the plane of its orbit. If the electron experiences a torque $T$, then
A particle is moving in an elliptical orbit as shown in the figure. If $p$, $L$, and $r$ denote the linear momentum, angular momentum, and position vector of the particle (from focus $O$) respectively at a point $A$, then the direction of $\alpha = p \times L$ is along
particle is moving in an elliptical orbit
The Entropy ($S$) of a black hole can be written as $S = \beta k_B A$, where $k_B$ is the Boltzmann constant and $A$ is the area of the black hole. Then $\beta$ has dimension of
27 drops of mercury coalesce to form a bigger drop. What is the relative increase in surface energy?
A neutral conducting solid sphere of radius $R$ has two spherical cavities of radii $a$ and $b$ as shown in the figure. The center-to-center distance between the two cavities is $c$. $q_a$ and $q_b$ charges are placed at the centers of cavities respectively. The force between $q_a$ and $q_b$ is
A neutral conducting solid sphere of radius
The boiling point of water is higher than liquid HF. The reason is that:
In Bohr's model of the atom, the radius of a hydrogen atom in the ground state is $r_1$ and the radius of a He+ ion in the ground state is $r_2$. Which of the following is correct?
During the preparation of NH3 in Haber’s process, the promoter(s) used is/are:
In a Young's double slit experiment, the intensity of light at a point on the screen where the path difference between the interfering waves is $\lambda$ (where $\lambda$ is the wavelength of light used) is $1$. The intensity at a point where the path difference is $\frac{\lambda}{4}$ will be (assume two waves have the same amplitude)
Two infinite line charges parallel to each other are moving with a constant velocity $v$ in the same direction as shown in the figure. The separation between two line charges is $d$. The magnetic attraction balances the electric repulsion when, [e = speed of light in free space]
Two infinite line charges parallel to each other are moving with
In Young's double slit experiment with monochromatic light, the maximum intensity is 4 times the minimum intensity in the interference pattern. What is the ratio of the intensities of the two interfering waves?
Avogadro's law is valid for
XeF2, NO2, HCN, ClO2, CO2 Identify the non-linear molecule-pair from the above mentioned molecules.
The number of unpaired electrons in $Mn^{2+}$ ion is
The correct pair of electron affinity order is:
If a string suspended from the ceiling is given a downward force $F_1$, its length becomes $L_1$. Its length is $L_2$ if the downward force is $F_2$. What is its actual length?
The number of atoms in body-centred and face-centred cubic unit cell respectively are
The metal-pair that can produce nascent hydrogen in alkaline medium is:
Sodium nitroprusside is:
Oxidation states of Cr in K2Cr2O7 and CrO5 are, respectively:
The kinetic energy ($E_k$) of a particle moving along the X-axis varies with its position ($X$) as shown in the figure. The force acting on the particle at $X = 10$ m is
particle moving along the X-axis varies with its position
Two wires $A$ and $B$ of the same length are made of the same material. The Load ($F$) vs. elongation ($x$) graph for these two wires is shown in the figure. Then which of the following statement(s) is/are true?
Two wires A and B of the same length are made of same material Load
Pick the correct statement: