List of top Physics Questions

There are two cubical Gaussian surface carrying charges as shown. Find ratio of fluxes through surface $C_1$ and $C_2$:

The equivalent resistance of the following network is _____ $ \Omega $.

In the figure, a ray of light is incident on a transparent liquid contained in a thin glass box at an angle of 45° with its one face. The emergent ray passes along the face AB. Find the refractive index of the liquid.

A proton is taken from point P1 to point P2, both located in an electric field. The potentials at points P1 and P2 are -5 V and +5 V respectively. Assuming that kinetic energies of the proton at points P1 and P2 are zero, the work done on the proton is:

A uniform wire of diameter $d$ carries a current of $100 \, \text{mA}$ when the mean drift velocity of electrons in the wire is $v$. For a wire of diameter $\frac{d}{2}$ of the same material to carry a current of $200 \, \text{mA}$, the mean drift velocity of electrons in the wire is

Water falls from 100 metre height. What will be temperature rise per kg of water due to fall?
$g = 10 \, \text{m/s}^2$, specific heat of water = 4200 Joule/kg°C

Two resistances combine in series order to provide 50 ohms resultant resistance, and when they combine in parallel order, they provide 8 ohms resultant resistance. Then the value of each resistance is:

Obtain an expression for the electric potential due to a small dipole of dipole moment $ \vec{p} $, at a point $ \vec{r} $ from its centre, for much larger distances compared to the size of the dipole.

Force between two point charges $ q_1 $ and $ q_2 $ placed in vacuum at a distance $ r \, \text{cm} $ apart is $ F $. Force between them when placed in a medium having dielectric $ K = 5 $ at $ r/5 \, \text{cm} $ apart will be:

If $\phi$ is the work function of photosensitive material in eV and light of wavelength of numerical value $\lambda = \frac{hc}{e}$ metre, is incident on it with energy above its threshold value at an instant then the maximum kinetic energy of the photo-electron ejected by it at that instant (Take $h$-Planck’s constant, $c$-velocity of light in free space) is (in SI units):

The figure shows a circuit with three ideal batteries. Find the magnitude and direction of currents in the branches AG, BF and CD.

A 2.0 cm segment of wire, carrying 5.0 A current in positive y-direction lies along the y-axis, as shown in the figure. The magnetic field at a point (3 m, 4 m, 0) due to this segment (part of a circuit) is:

Two long straight wires 1 and 2 are kept as shown in the figure. The linear charge density of the two wires are $\lambda$ 1 = 10 C/m and $\lambda$2 = -20 C/m. Find the net force F experienced by an electron held at point P:

In the circuit shown, the current in the 1Ω resistor is:

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

In the above diagram, a strong bar magnet is moving towards solenoid-2 from solenoid-1. The direction of induced current in solenoid-1 and that in solenoid-2, respectively, are through the directions :

A sheet is placed on a horizontal surface in front of a strong magnetic pole. A force is needed to :
A. hold the sheet there if it is magnetic.
B. hold the sheet there if it is non-magnetic.
C. move the sheet away from the pole with uniform velocity if it is conducting.
D. move the sheet away from the pole with uniform velocity if it is both, non-conducting and non-polar.
Choose the correct statement(s) from the options given below :

The ratio of heat dissipated per second through the resistance 5 ohm and 10 ohm in the circuit given below is :

Given below are two statements:
Statement I: Atoms are electrically neutral as they contain equal number of positive and negative charges.
Statement II: Atoms of each element are stable and emit their characteristic spectrum.
In the light of the above statements, choose the most appropriate answer from the options given below

If $\vec{a}$ and $\vec{b}$ make an angle $\cos^{-1}\left(\frac{5}{9}\right)$ with each other, then \[ |\vec{a} + \vec{b}| = \sqrt{2} |\vec{a} - \vec{b}| \quad \text{for } |\vec{a}| = n |\vec{b}|. \] The integer value of $n$ is _____.

A galvanometer with resistance 100 Ω gives full-scale deflection with a current of 2 mA. The resistance required to convert the galvanometer into an ammeter of range 0 to 20 A is nearly:

A long solenoid is formed by winding insulated copper wire at the rate of 20 turns per cm. The current required to produce a magnetic field of 20 mT inside the solenoid at its center would be:

A train is moving with a speed of 12 m/s on rails which are 1.5 m apart. To negotiate a curve radius of 400 m, the height by which the outer rail should be raised with respect to the inner rail is (Given, $ g = 10 \, \text{m/s}^2 $):

A square loop with each side 1 cm, carrying a current of 10 A, is placed in a magnetic field of 0.2 T. The direction of the magnetic field is parallel to the plane of the loop. The torque experienced by the loop is .
Fill in the blank with the correct answer from the options given below

A square loop PQRS having 10 turns, area $3.6 \times 10^{-3} \, \text{m}^2$, and resistance $100 \, \Omega$ is slowly and uniformly being pulled out of a uniform magnetic field of magnitude $B = 0.5 \, \text{T}$ as shown. Work done in pulling the loop out of the field in $1.0 \, \text{s}$ is ______ $ \times 10^{-6} \, \text{J} $.