List of top Physics Questions

Two points A and B on the axis of a circular current loop are at distances of 4 cm and $ 3\sqrt{3} $ cm from the center of the loop. If the ratio of the induced magnetic fields at points A and B is 216:125, the radius of the loop is:

A rectangular loop of sides 25 cm and 10 cm carrying a current of 10 A is placed with its longer side parallel to a long straight conductor 10 cm apart carrying current 25 A. The net force on the loop is:

A charge is kept at the central point P of a cylindrical region. The two edges subtend a half-angle $\theta$ at P, as shown in the figure. When $\theta = 30$ , then the electric flux through the curved surface of the cylinder is $Φ$. If $\theta= 60\degree$ , then the electric flux through the curved surface becomes $Φ/√𝑛$, where the value of n is______.

A pendulum clock loses 10.8 seconds a day when the temperature is $ 38^\circ C $ and gains 10.8 seconds a day when the temperature is $ 18^\circ C $. The coefficient of linear expansion of the metal of the pendulum clock is:

37 g of ice at 0Â°C is mixed with 74 g of water at 70Â°C. The resultant temperature is:

If the speed of sound in air at 0°C is 331 m/s, the speed of sound in air at 35°C is:

A table tennis ball has radius $(3/2) × 10^{−2} $m and mass $(22/7) × 10^{−3} $kg. It is slowly pushed down into a swimming pool to a depth of 𝑑 = 0.7 m below the water surface and then released from rest. It emerges from the water surface at speed 𝑣, without getting wet, and rises up to a height 𝐻. Which of the following option(s) is(are) correct?[Given: $\pi = 22/7, g = 10 m s ^{−2} $, density of water = $1 × 10^3 kg\ m^{−3}$ , viscosity of water = $1 × 10^{−3}$ Pa-s.]

Obtain the formula of the relationship of drift velocity and potential difference.

The temperature at which the rms speed of oxygen molecules is 75\% of the rms speed of nitrogen molecules at a temperature of $ 287^\circ C $ is:

In the diodes shown in the diagrams, which one is reverse biased?

An inductor of inductive reactance $ R $, a capacitor of capacitive reactance $ 2R $, and a resistor of resistance $ R $ are connected in series to an AC source. The power factor of the series LCR circuit is?

The concentration of electrons in an intrinsic semiconductor is $ 6 \times 10^{15} \, m^{-3} $. On doping with an impurity, the electron concentration increases to $ 4 \times 10^{22} \, m^{-3} $. In thermal equilibrium, the concentration of the holes in the doped semiconductor is:

A straight wire of length 20 cm carrying a current of $\frac{3}{\pi ^2} \, \text{A} $ is bent in the form of a circle. The magnetic field at the centre of the circle is.

Given that the surface charge density on a sphere is 200 μC/m², what is the electric field at the surface of the sphere?

In hydrogen atom, what is the ionization potential of the electron in the ground state?

If the tension applied to a string is decreased by 36\%, then the fundamental frequency of the transverse waves of the string is:

Two blocks of masses $ m $ and $ 2m $ are connected by a massless string which passes over a fixed frictionless pulley. If the system of blocks is released from rest, the speed of the centre of mass of the system of two blocks after a time of 5.4 s is (Acceleration due to gravity = 10 ms$^{-2}$)

A box of mass 20 𝑘𝑔 is pulled at constant speed across a floor by a rope. The rope makes an angle of 45° with the horizontal. Assuming that friction is negligible, the work done in pulling the box by a distance of 20 𝑚 is _____ 𝐽 (rounded off to the nearest integer). (Use $𝑔 = 9.8 𝑚𝑠^{−2}$)

In the following diagram, the work done in moving a point charge from point P to point A, B and C are $ W_A, W_B, W_C $ respectively. Then (A, B, C are points on semicircle and point charge $ q $ is at the centre of semicircle)

If the peak value of the magnetic field of an electromagnetic wave is $ 30 \times 10^{-9} \, \text{T} $, then the peak value of the electric field is

A ball at point ‘O’ is at a horizontal distance of 7 m from a wall. On the wall, a target is set at point ‘C’. If the ball is thrown from ‘O’ at an angle $ 37^\circ $ with horizontal aiming the target ‘C’. But it hits the wall at point ‘D’ which is a vertical distance $ y_0 $ below ‘C’. If the initial velocity of the ball is 15 m/s, find $ y_0 $. (Given $ \cos 37^\circ = \frac{4}{5} $)

Young double slit arrangement is placed in a liquid medium of 1.2 refractive index. Distance between the slits and screen is 2.4 m.
Slit separation is 1 mm. The wavelength of incident light is 5893 Å. The fringe width is:

A long straight rod of diameter 4 mm carries a steady current $ i $. The current is uniformly distributed across its cross-section. The ratio of the magnetic fields at distances 1 mm and 4 mm from the axis of the rod is.

A straight wire of resistance $R$ is bent in the shape of a square. A cell of emf 12 V is connected between two adjacent corners of the square. The potential difference across any diagonal of the square is:

The sphere A of mass $ m $ moving with a constant velocity hits another sphere B of mass $ 2m $ at rest. If the coefficient of restitution is 0.4, the ratio of the velocities of the spheres A and B after collision is