List of top Physics Questions asked in WBJEE

A circular coil is placed near a current-carrying conductor, both lying on the plane of the paper. The current is flowing through the conductor in such a way that the induced current in the loop is clockwise as shown in the figure. The current in the wire
A circular coil is placed near a current-carrying conductor
 
A uniform rope of length 4 m and mass 0.4kg is held on a frictionless table in such a way that 0.6m of the rope is hanging over the edge. The work done to pull the hanging part of the rope onto the table is, (Assuming g=10m/s2) 
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
If the kinetic energies of an electron, an alpha particle, and a proton having the same de-Broglie wavelength are $\varepsilon_1, \varepsilon_2, \varepsilon_3$ respectively, then
27 drops of mercury coalesce to form a bigger drop. What is the relative increase in surface energy?
The expression $A(A + B) + (B + AA)(A + B)$ simplifies to
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?
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
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
Suppose in a hypothetical world the angular momentum is quantized to be even integral multiples of $\frac{h}{2}$. The largest possible wavelength emitted by hydrogen atoms in the visible range in a world according to Bohr's model will be (consider $h_e = 1224$ MeV-fm)
The human eye has an approximate angular resolution of $\theta = 5.8 \times 10^{-4}$ rad, and a typical photo printer prints a minimum of 300 dpi (dots per inch, $1$ inch = $2.54$ cm). At what minimal distance $d$ should the printed page be held so that one does not see the individual dots?
The electric potential for an electric field directed parallel to the X-axis is shown in the figure. Choose the correct plot of electric field strength.
Consider two concentric conducting spheres of radii $R$ and $2R$ respectively. The inner sphere is given a charge $+Q$. The other sphere is grounded. The potential at $r = \frac{3R}{2}$ is
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
A battery of emf E and internal resistance r is connected with an external resistance R as shown in figure. The battery will act as a constant voltage source if:
A battery of emf E and internal resistance r
A straight wire is placed in a magnetic field that varies with distance $x$ from origin as $B = B_0 (2 - \frac{x}{n}) \hat{k}$. The ends of the wire are at $(a, 0)$ and $(2n, 0)$ and it carries a current $I$. If the force on the wire is $F = 1 B_0 \left(\frac{k a}{2}\right) \hat{j}$, then the value of $k$ is
In a closed circuit there is only a coil of inductance $L$ and resistance $100\ \Omega$. The coil is situated in a uniform magnetic field. All of a sudden, the magnetic flux linked with the circuit changes by $5$ Weber. What amount of charge will flow in the circuit as a result?
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 Zener diode having a breakdown voltage $V_z = 6$ V is used in a voltage regulator circuit as shown in the figure. The minimum current required to pass through the Zener to act as a voltage regulator is $10$ mA and the maximum allowed current through the Zener is $40$ mA. The maximum value of $R_\delta$ for Zener to act as a voltage regulator is
A Zener diode having a breakdown voltage
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
Certain amount of an ideal gas is taken from its initial state 1 to final state 4 through the paths 1 → 2 → 3 → 4 as shown in the figure AB, CD, EF are all isotherms. If $v_p$ is the most probable speed of the molecules, then:
Certain amount of an ideal gas is taken from its initial state 1 to final
A particle is subjected to two simple harmonic motions in the same direction having equal amplitudes and equal frequency. If the resultant amplitude is equal to the amplitude of the individual motion, the phase difference $(\delta)$ between the two motions is
One mole of a diatomic ideal gas undergoes a process shown in the P-V diagram. The total heat given to the gas (In 2 = 0.7) is:
One mole of a diatomic ideal gas undergoes a process
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
Given: The percentage error in the measurements of A, B, C, and D are respectively 4%, 2%, 3%, and 1%. The relative error in $Z = \frac{A^4 B^{1/3}}{C D^{3/2}}$ is