List of top Physics Questions

A fully charged capacitor has a capacitance $'C'$. It is discharged through a small coil of resistance wire embedded in a thermally insulated block of specific heat capacity $s$ and mass $m$. If the temperature of the block is raised by $\Delta T$, the potential difference $V$ across the capacitance is:

A parallel plate capacitor is made by stacking $n$ equally spaced plates connected alternatively. If the capacitance between any two adjacent plates is $C$, then the resultant capacitance is :

Two thin wire rings each having a radius $R$ are placed at a distance $d$ apart with their axes coinciding. The charges on the two rings are $+ q$ and $- q$. The potential difference between the centres of the two rings is :

The figure shows a system of two concentric spheres of radii $r_1$, and $r_2$ and kept at temperatures $T_1$ and $T_2$, respectively. The radial rate of flow of heat in a substance between the two concentric spheres, is proportional to :

If reduction factor of a tangent galvanometer is $900 \,mA$, then the current through it to produce a deflection of $ 45^{\circ} $ is

A magnetic needle is kept in a non-uniform magnetic field. It experiences:

In uniform circular motion, the factor that remains constant is

The maximum range of a gun on horizontal terrain is $16 \,km$, if $g=10 \,m / s ^{2}$. What must be the muzzle velocity of the shell?

A projectile is fired at $30^{\circ}$ with momentum $p$. Neglecting friction, the change in kinetic energy, when it returns back to the ground, will be

A particle is moving under the influence of a force which is fixed in magnitude and acting at an angle $\theta$ in the direction of motion. The path described by the particle is

A projectile can have the same range $R$ for two angles of projection. If $t_1$ and $t_2$ be the times of flights in the two cases, then the product of the two times of flights is proportional to :

A bullet is fired with a speed of $1000 \,m/s$ in order to hit a target $100 \,m$ away. If $g = 10 \,m/s^2$ . The gun should be aimed

The horizontal range of a projectile is $400\, m$. The maximum height attained by it will be:

In Young's double slit experiment, fringe width decreases by 25% when apparatus is immersed in a liquid. Refractive index of the liquid is

When interference is observed, energy is

In an interference experiment, distance between the slits is 2 mm and screen is placed at distance 1 m from the slits. Fourth dark fringe is formed exactly opposite to one of the slits. Wavelength of light used in nm is

If work function of a metal is $4.2\,eV$, the cut off wavelength is:

The pressure exerted by an electromagnetic wave of intensity $I\left( W / m ^{2}\right)$ on a non-reflecting surface is: $[c$ is the velocity of light $]$

Two light rays having the same wavelength $\lambda$ in vacuum are in phase initially. Then the first ray travels a path $L_1$ through a medium of refractive index $n_1$ while the second ray travels a path of length $L_2$ through a medium of refractive index $n_2$. The two waves are then combined to produce interference. The phase difference between the two waves is

Turning effect is produced by

A block of mass 2 kg rests on a plane inclined at an angle of $ {{30}^{o}} $ with the horizontal. The coefficient of friction between the block and surface is 0.7. The frictional force acting on the block is:

Water of volume 2 L in a container is heated with a coil of 1 kW at 27$^{\circ}$C. The lid of the container is open and energy dissipates at rate of 160 J/s. In how much time temperature will rise from 27$^{\circ}$C to 77$^{\circ}$C? [Specific heat of water is 4.2 kJ/kg]

A convex lens is in contact with concave lens. The magnitude of the ratio of their focal length is of the ratio of their focal length is $\frac{3}{2}$ Their equivalent focal length is 30 cm. What are their individual focal lengths ?

The exposure time of a camera lens at $ f/2.8 $ setting is $1/200$ s. The correct exposure time at $ f/5.6 $ setting is: