List of top Physics Questions asked in JEE Main

A particle is placed at the point \( A \) of a frictionless track \( ABC \) as shown in the figure. It is gently pushed toward the right. The speed of the particle when it reaches the point \( B \) is: (Take \( g = 10 \, \text{m/s}^2 \)).

Given below are two statements:
Statement (I): Viscosity of gases is greater than that of liquids. 
Statement (II): Surface tension of a liquid decreases due to the presence of insoluble impurities. 
In the light of the above statements, choose the most appropriate answer from the options given below:

When the displacement of a simple harmonic oscillator is one third of its amplitude, the ratio of total energy to the kinetic energy is \(\frac{x}{ 8}\) , where x = _________.

The electric current through a wire varies with time as \(I = I_0 + \beta t\) where \( I_0 = 20 \, \text{A} \) and \( \beta = 3 \, \text{A/s} \). The amount of electric charge that crosses through a section of the wire in \( 20 \, \text{s} \) is:

A body starts moving from rest with constant acceleration and covers displacement \(S_1\) in the first \((p - 1)\) seconds and \(S_2\) in the first \(p\) seconds. The displacement \(S_1 + S_2\) will be made in time:

A block of mass 100 kg slides over a distance of 10 m on a horizontal surface. If the coefficient of friction between the surfaces is 0.4, then the work done against friction (in J) is:

If the radius of curvature of the path of two particles of the same mass are in the ratio \( 3:4 \), then in order to have constant centripetal force, their velocities will be in the ratio of:

A galvanometer having coil resistance 10 Ω shows a full scale deflection for a current of 3 mA. For it to measure a current of 8 A, the value of the shunt should be:

The de-Broglie wavelength of an electron is the same as that of a photon. If the velocity of the electron is 25% of the velocity of light, then the ratio of the K.E. of the electron to the K.E. of the photon will be:

The deflection in a moving coil galvanometer falls from 25 divisions to 5 divisions when a shunt of \( 24 \, \Omega \) is applied. The resistance of the galvanometer coil will be:

A biconvex lens of refractive index 1.5 has a focal length of 20 cm in air. Its focal length when immersed in a liquid of refractive index 1.6 will be:

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 :

At what distance above and below the surface of the earth a body will have the same weight (take radius of earth as R)?

A capacitor of capacitance 100 μF is charged to a potential of 12 V and connected to a 6.4 mH inductor to produce oscillations. The maximum current in the circuit would be:

The explosive in a hydrogen bomb is a mixture of \( ^2\text{H} \), \( ^3\text{H} \), and \( ^6\text{Li} \) in some condensed form. The chain reaction is given by\[_3^6\text{Li} + _0^1\text{n} \rightarrow _2^4\text{He} + _1^3\text{H}\]\[_1^2\text{H} + _1^3\text{H} \rightarrow _2^4\text{He} + _0^1\text{n}\]During the explosion, the energy released is approximately ____.[Given: \( M(\text{Li}) = 6.01690 \, \text{amu} \), \( M(^3\text{H}) = 2.01471 \, \text{amu} \), \( M(_2^4\text{He}) = 4.00388 \, \text{amu} \), and \( 1 \, \text{amu} = 931.5 \, \text{MeV} \)]

When a hydrogen atom going from \( n = 2 \) to \( n = 1 \) emits a photon, its recoil speed is \( \frac{x}{5} \) m/s. Where \( x = \, \) _____. (Use: mass of hydrogen atom \( = 1.6 \times 10^{-27} \, \text{kg} \))

A ball rolls off the top of a stairway with horizontal velocity \( u \). The steps are \( 0.1 \, \text{m} \) high and \( 0.1 \, \text{m} \) wide. The minimum velocity \( u \) with which the ball just hits the step 5 of the stairway will be \( \sqrt{x} \, \text{m/s} \) where \( x = \) _____. (Use \( g = 10 \, \text{m/s}^2 \)).

A square loop of side \( 10 \, \text{cm} \) and resistance \( 0.7 \, \Omega \) is placed vertically in the east-west plane. A uniform magnetic field of \( 0.20 \, \text{T} \) is set up across the plane in the northeast direction. The magnetic field is decreased to zero in \( 1 \, \text{s} \) at a steady rate. Then, the magnitude of the induced emf is \( \sqrt{x} \times 10^{-3} \, \text{V} \). The value of \( x \) is _____.

A cylinder is rolling down an inclined plane of inclination \( 60^\circ \). Its acceleration during rolling down will be \( \frac{x}{\sqrt{3}} \, \text{m/s}^2 \), where \( x = \) _____. (Use \( g = 10 \, \text{m/s}^2 \)).

The magnetic potential due to a magnetic dipole at a point on its axis situated at a distance of 20 cm from its center is \( 1.5 \times 10^{-5} \, \text{Tm} \). The magnetic moment of the dipole is _______ \( \text{Am}^2 \).
(Given: \( \frac{\mu_0}{4\pi} = 10^{-7} \, \text{TmA}^{-1} \))

Match List I with List II

List I	List II
A. \( \oint \vec{B} \cdot d\vec{l} = \mu_0 i_c + \mu_0 \epsilon_0 \frac{d\phi_E}{dt} \)	I. Gauss' law for electricity
B. \( \oint \vec{E} \cdot d\vec{l} = -\frac{d\phi_B}{dt} \)	II. Gauss' law for magnetism
C. \( \oint \vec{E} \cdot d\vec{A} = \frac{Q}{\epsilon_0} \)	III. Faraday law
D. \( \oint \vec{B} \cdot d\vec{A} = 0 \)	IV. Ampere – Maxwell law

Choose the correct answer from the options given below

The potential energy function (in joules) of a particle in a region of space is given as\[U = (2x^2 + 3y^3 + 2z).\]Here \( x \), \( y \), and \( z \) are in meters. The magnitude of the \( x \)-component of force (in newtons) acting on the particle at point \( P (1, 2, 3) \) m is:

In the given circuit, the breakdown voltage of the Zener diode is 3.0 V. What is the value of I_z ?

An electric toaster has resistance of \( 60 \, \Omega \) at room temperature \( (27^\circ \text{C}) \). The toaster is connected to a 220 V supply. If the current flowing through it reaches 2.75 A, the temperature attained by the toaster is around: (if \( \alpha = 2 \times 10^{-4} / ^\circ \text{C} \))

Match List-I with List-II. 
\[ \begin{array}{|c|c|c|} \hline \text{List-I} & & \text{List-II} \\ \hline \text{A. Coefficient of viscosity} & & \text{I.} \; [M L^2 T^{-2}] \\ \text{B. Surface Tension} & & \text{II.} \; [M L^2 T^{-1}] \\ \text{C. Angular momentum} & & \text{III.} \; [M L^1 T^{-1}] \\ \text{D. Rotational kinetic energy} & & \text{IV.} \; [M L^0 T^{-2}] \\ \hline \end{array} \]