List of top Physics Questions asked in JEE Main

A Zener diode has a voltage rating of 10 volts and the maximum power drop across the Zener diode is 0.5 watt. What resistance (in Ohm) should be connected in series with the Zener diode so that it can be operated safely by a battery of 25 volts?
A force \( \vec{F} = (5\hat{i} + 2\hat{j}) \, \mathrm{N} \) is acting for 2 s on an object of mass 0.1 kg, which is initially at rest at the origin. Find the final position.
A solenoid of radius 2 cm and with 125 turns is kept in a uniform magnetic field of 0.4 T carries a current of 1A. The axis of the solenoid makes an angle of \( 30^\circ \) with the field. The torque acting on the solenoid will be:
Statement-1: Two gases \( \mathrm{H_2} \) and \( \mathrm{O_2} \) are having the same average kinetic energy, then they have the same temperature.
Statement-2: \( \mathrm{H_2} \) and \( \mathrm{O_2} \) will have the same \( v_{\mathrm{rms}} \) at the same temperature.
In a YDSE experiment, a sheet of thickness \( t \) and \( \mu = 1.56 \) is introduced at a slit. The central maxima shifts to the position of the \( 7^{\text{th}} \) maxima. The wavelength of light is 480 nm. If \( t = x \, \mu\text{m} \), find the value of \( x \).
Material of \( \mu_r = 400 \) is present inside a solenoid where the magnetic field is found to be \( 1 \, \mathrm{T} \). If the magnetic intensity here is \( \alpha \times 10^5 \) SI units, find \( \alpha \) (\( \mu_0 = 4\pi \times 10^{-7} \, \mathrm{H/m} \)).
Assertion (A): Free charge cannot exist inside a conductor.
Reason (R): If a free charge is kept between the plates of a capacitor, then it will experience force and it will drift.

Two setups of polarizers are used to polarize natural light as shown. Find the value of the ratio of intensities \( I_1/I_2 \). The angle of axes is shown in the figure from a fixed axis. 


 

As shown in the figure, for a biconvex lens the focal length is \( f \) and both radii of curvature are \( R \). Find the value of \( f/R \) (\( \mu = 1.4 \)): 

A galvanometer is used for making an ammeter of range 500 mA when a shunt of 2 \(\Omega\) is used. The same galvanometer is used for making a voltmeter of range 10V when a resistance of 470 \(\Omega\) is used in series. Then find the resistance of the galvanometer.
Bullets are fired from a gun in all the direction at all angles. Maximum range on horizontal ground is \(6.4\) m. Find speed of bullet at the time of firing.

Find magnitude of acceleration of particle at \(t = 5\,\text{s}\). If velocity–time graph is given as shown in figure. 

Two forces are acting on a body: \[ \vec{F}_1 = 3\hat{i} -5\hat{j} +2\hat{k} \] \[ \vec{F}_2 = 8\hat{i} +2\hat{j} -3\hat{k} \] The displacement of the body is \(25\,\text{m\) along the direction \(3\hat{i}-4\hat{j}\). Find the work done.}
\( A_1^{n_1^+} + n_1 e^- \rightarrow A_1 \)
\( A_2 \rightarrow A_2^{n_2^+} + n_2 e^- \)
Hydrolysis of sucrose follows 1st order kinetics to produce glucose and fructose. If \( t_{1/2} \) for decomposition of sucrose is 3 hr, find the % of sucrose left after 6 hr.
A point source is kept at centre of a sphere. The intensity of light at point \(A\) is \(I\). Find intensity at point \(B\).
Find the ratio of momentum of photons of 1\textsuperscript{st and 2\textsuperscript{nd} line of Balmer series of hydrogen atom.}
Two wires are joined together and elongated with force as shown in the figure. If \( \dfrac{Y_1}{Y_2} = \dfrac{20}{11} \), find \( \dfrac{\ell_1}{\ell_2} \) so that they have same elongation.
If \(P\) is the midpoint of median, find distance of COM from \(P\).
A small drop of mass \(1\,g\) starts falling from rest from a height of \(1\,km\). When it reaches the ground with speed \(5\,m/s\), magnitude of work done by resistance force is \(x\times10^{-3}\,J\). Find \(x\).
Shortest wavelength of Lyman series is \(x\). Find the difference of wavelengths of first Balmer and second Balmer line in terms of \(x\).
Unpolarised light with intensity \(I_0\) is incident on a polariser. Find angle between axis of polariser and analyser such that intensity of emergent light becomes \( \frac{3I_0}{8} \).
A cube of side \(1\,\text{mm}\) is placed at centre of circular coil of radius \(10\,\text{cm}\). Current flowing in coil is \(2\,A\). Find magnetic field energy stored in cube. (\(\pi = 3.14\))
Bulk modulus of an ideal gas for isothermal process initially is \(B\). Gas is compressed from volume \(V_0\) to \( \frac{V_0}{3} \) isothermally. Find the work done by gas.
Electric field in space is given by \[ \vec{E} = 2x\hat{i} + 3y^2\hat{j} + 4\hat{k} \] A charge \(q = 3\,C\) is taken from \(r_1(0,-1,-3)\) to \(r_2(5,1,2)\). Find magnitude of \( \Delta U \).