List of top Questions asked in WBJEE

The number of unpaired electrons in $Mn^{2+}$ ion is
The de-Broglie wavelength ($\lambda$) for electron ($e$), proton ($p$), and He²⁺ ion ($\alpha$) are in the following order, Speed of $e$, $p$, and $\alpha$ are the same
The average speed of $H_2$ at $T_1$ K is equal to that of $O_2$ at $T_2$ K. The ratio $T_1:T_2$ is
A metal ($M$) forms two oxides. The ratio $M:O$ (by weight) in the two oxides are $25:4$ and $25:6$. The minimum value of atomic mass of $M$ is
Which of the following is the correct set of four quantum numbers ($n$, $l$, $m$, $s$)?
$C_6H_6(\text{liquid}) + \frac{15}{2} O_2(\text{gas}) \rightarrow 6 CO_2(\text{gas}) + 3 H_2O(\text{liquid})$ Benzene burns in oxygen according to the above equation. What is the volume of oxygen (at STP) needed for complete combustion of $39$ grams of liquid benzene?
The enol form in which ethyl-3-oxobutanoate exists is
The major product of the following reaction is $F_3C \rightarrow CH = CH_2 + HBr$
The correct order of relative stability of the given conformers of n-butane is
order of relative stability
How much solid oxalic acid (molecular weight $126$) has to be weighed to prepare $100$ mL of exactly $0.1$ N oxalic acid solution in water?
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?
What is the correct order of acidity of salicylic acid, 4-hydroxybenzoic acid, and 2,6-dihydroxybenzoic acid?
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?
As shown in the figure, a rectangular loop of length $a$ and width $b$ and made of a conducting material of uniform cross-section is kept in a horizontal plane where a uniform magnetic field of intensity $B$ is acting vertically downward. The resistance per unit length of the loop is $\lambda \, \Omega / m$. If the loop is pulled with uniform velocity $v$ in a horizontal direction, which of the following statement(s) is/are true?
rectangular loop of length 'a' and width 'b' and made of a conducting material of uniform cross-section
A sample of hydrogen atom in its ground state is radiated with photons of $10.2$ eV energies. The radiation from the sample is absorbed by excited ionized He+. Then which of the following statement(s) is/are true?
A hemisphere of radius $R$ is placed in a uniform electric field $E$ so that its axis is parallel to the field. Which of the following statement(s) is/are true?
hemisphere of radius R is placed in a uniform electric field
How many monobrominated product(s) (including stereoisomers) would form in the free radical bromination of n-butane?
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
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
Three concentric metallic shells $A$, $B$, and $C$ of radii $a$, $b$, and $c$ have surface charge densities $+\sigma$, $-\sigma$, and $\sigma+$ respectively. The potential of shell $B$ is
Three concentric metallic shells
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
Find the equivalent capacitance between $A$ and $B$ of the following arrangement:
equivalent capacitance
A golf ball of mass $50$ gm placed on a tee is struck by a golf club. The speed of the ball as it leaves the tee is $100$ m/s, and the time of contact on the ball is $0.02$ s. If the force decreases to zero linearly with time, then the force at the beginning of the contact is
A horizontal semi-circular wire of radius $r$ is connected to a battery through two similar springs $X$ and $Y$ to an electric cell, which sends current $I$ through it. A vertically downward uniform magnetic field $B$ is applied on the wire, as shown in the figure. What is the force acting on each spring?
A horizontal semi-circular wire of radius
One mole of an ideal monatomic gas expands along the polytrope $P V^3 = \text{constant}$ from $V_1$ to $V_2$ at a constant pressure $P_1$. The temperature during the process is such that molar specific heat $C_v = \frac{3R}{2}$. The total heat absorbed during the process can be expressed as