List of top Physics Questions

The coefficient of viscosity for hot air is
The capacitance of a spherical conductor of radius $1 \,m$ is
Reverse saturation current of diode
Photoelectric Effect and Raman Effect can be explained on the basis of
Monochromatic radiation emitted when electron on hydrogen atom jumps from first excited to the ground state irradiates a photosensitive material. The stopping potential is measured to be $3.57\, V.$ The threshold frequency of the material is
$[ML^{3}T^{-3}A^{-2}]$ is the dimensional formula of
In an $LCR$ circuit shown in the following figure, what will be the readings of the voltmeter across the resistor and ammeter if an $a.c.$ source of $220V$ and $100\, Hz$ is connected to it as shown?
In a Young?? double slit experiment with light of wavelength $\lambda$, fringe pattern on the screen has fringe width $\beta$. When two thin transparent glass (refractive index $\mu$) plates of thickness $t_1$ and $t_2$ $(t_1 > t_2)$ are placed in the path of the two beams respectively, the fringe pattern will shift by a distance
In a convex lens of focal length $F$, the minimum distance between an object and its real image must be
If radius of the $1^{st}$ orbit of $H$-atom is $0.0529 \,nm$ then the radius of its $3^{rd}$ orbit is
Find the voltage drop across a capacitor connected with a resistance and a battery of $60\, V$ in series after a long time.
Dimensional formula of $\Delta Q$, heat supplied to the system is
Vibrational energy of diatomic molecule corresponding to each degree of freedom is kT. For every molecule, vibrational degree of freedom is 2.
More energy is released in fusion than fission. More number of nucleons take part in fission.
Assuming the earth to be a sphere of uniform density, the acceleration due to gravity inside the earth at a distance of $r$ from the centre is proportional to
Assume that a neutron breaks into a proton and an electron. The energy released during this process is : (Mass of neutron $= 1.6725 ??10^{-27}\, kg$, Mass of proton $= 1.6725 ??10^{-27}\, kg$, Mass of electron $= 9 ??10^{-31}\, kg$ )
An object $2.4\, m$ in front of a lens forms a sharp image on a film $12\, cm$ behind the lens. A glass plate $1\, cm$ thick, of refractive index $1.50$ is interposed between lens and film with its plane faces parallel to film. At what distance (from lens) should object shifted to be in sharp focus on film ?
An insect crawls up a hemispherical surface very slowly. The coefficient of friction between the insect and the surface is 1/3. If the line joining the centre of the hemispherical surface to the insect makes an angle a with the vertical, the maximum possible value of a so that the insect does not slip is given by
An artificial satellite moving in a circular orbit around the earth has a total (kinetic $+$ potential) energy $E_0$. Its potential energy is
A wooden wheel of radius R is made of two semicircular parts (see figure). The two parts are held together by a ring made of a metal strip of cross sectional area S and length L. L is slightly less than 2?R. To fit the ring on the wheel, it is heated so that its temperature rises by ?T and it just steps over the wheel. As it cools down to surroundifng temperature, it presses the semicircular parts together. If the coefficient of linear expansion of the metal is $R$, and its Young's modulus is Y, the force that one part of the wheel applies on the other part is :
A thin liquid film formed between a U-shaped wire and a light slider supports a weight of $1.5 ??10^{-2}\, N$ (see figure). The length of the slider is $30\, cm$ and its weight negligible. The surface tension of the liquid film is :
A spherical drop of capacitance 1 $\mu$F is broken into eight drops of equal radius. Then, the capacitance of each small drop is
A liquid in a beaker has temperature $\theta(t)$ at time $t$ and $\theta_0$ is temperature of surroundings, then according to Newton's law of cooling the correct graph between $log_{e}\left(\theta-\theta_{0}\right)$ and $t$ is :
A hypothetical atom has only three energy levels. The ground level has energy, $E_1 = - 8$ eV. The two excited states have energies, $E_2 = - 6$ eV and $E_3 = - 2$ eV. Then which of the following wavelengths will not be present in the emission spectrum of this atom?
A goods train accelerating uniformly on a straight railway track, approaches an electric pole standing on the side of track. Its engine passes the pole with velocity $u$ and the guard?s room passes with velocity $v$. The middle wagon of the train passes the pole with a velocity.