List of top Physics Questions

A soap bubble of diameter $7$ cm, its diameter is increased to $14$ cm. If change in its surface energy is $(15000 - x)\,\mu$J, find $x$. (Given surface tension = $0.04$ N/m)

A curve is given between the potential energy $U$ of a particle and its position on the $x$-axis as shown. Given: \[ \tan\theta_1 = 1,\qquad \tan\theta_2 = 3,\qquad \tan\theta_3 = -\frac{1}{2} \] If $F_{AB}$ is the force acting on the particle during motion from $A$ to $B$, similarly $F_{BC}$, $F_{CD}$ and $F_{DE}$ are the forces during $B$ to $C$, $C$ to $D$ and $D$ to $E$ respectively, arrange the magnitudes of these forces in decreasing order.

The exit surface of a prism with refractive index $n$ is coated with a material having refractive index $\dfrac{n}{2}$. When this prism is set for minimum angle of deviation, it exactly meets the condition of critical angle. The prism angle is ___.

Light is incident at such an angle so that minimum deviation takes place. Now a film of refractive index RI = $n/2$ is stick on other face such that total internal reflection takes place on second surface. Find angle of prism :

As shown in the figure, six rods of same geometry are connected and maintained at temperatures $100^\circ\text{C}$ and $40^\circ\text{C}$. The temperature at points $A$ and $B$ are:

Find the dimensions of the expression $ \dfrac{\varepsilon_0 E}{T} $, where $ \varepsilon_0 $, $E$, and $T$ are permittivity, electric field, and time respectively.

Rods $x$ and $y$ of equal dimensions but of different materials are joined as shown in figure. Temperatures of end points $A$ and $F$ are maintained at $100^\circ$C and $40^\circ$C respectively. Given the thermal conductivity of rod $x$ is three times of that of rod $y$, the temperature at junction points $B$ and $E$ are (close to):

A satellite is revolving around a planet in orbit radius of 1.5 R. Additional minimum energy required to transfer the satellite to the new orbit radius of 3R is (G and M are mass of satellite \& planet)

A particle moves along the $x$-axis and has its displacement $x$ varying with time $t$ according to the equation \[ x = c_0 (t^2 - 2) + c(t - 2)^2 \] where $c_0$ and $c$ are constants of appropriate dimensions. Which of the following statements is correct?

A cubical block of density $ \rho_b = 600\,\text{kg/m}^3 $ floats in a liquid of density $ \rho_l = 900\,\text{kg/m}^3 $. If the height of block is $H = 8.0\,\text{cm}$, then height of the submerged part is ________ cm.

Find out the correct energy for the ground state or energy transition. (Symbols have usual meaning and $n \to m$ gives the transition)

The equilateral triangular frame has current 2A. The side of frame is $4\sqrt{3}$ cm. Magnetic field at center C is:

There is a galvanometer of resistance $100\Omega$ and full scale current $I_g = 1$ mA. Find shunt resistance required to increase its range to $5$ mA.

A particle is falling under gravity. Air resistance on particle is F = $-$kv. Find correct option :

A sinusoidal electromagnetic wave is given by $ \vec{E} = 20 \sin \left( \frac{2}{300} x - 10^6 t \right) $ propagating in a non-magnetic material. Dielectric constant of the material is.

In the following configuration of charges. Find the net dipole moment of the system :

A particle of mass 2 kg initially at rest starts moving under the force $\vec{F} = 6t^2\hat{i} - 4at\hat{j}$.
If the speed of the particle at $t = 1$ s is $\sqrt{5}$, then the value of constant a is:

Three silicon diodes connected parallel to each other as shown. Forward voltage of diode is 0.7 V. Find current through diode A :

Two identical circular loops $P$ and $Q$ each of radius $r$ are lying in parallel planes such that they have common axis. The current through $P$ and $Q$ are $I$ and $4I$ respectively in clockwise direction as seen from $O$. The net magnetic field at $O$ is: