List of top Physics Questions

The barrier potential of a p-n junction depends on:
(a) type of semi conductor material
(b) amount of doping
(c) temperature
Which one of the following is correct?
If the kinetic energy of the particle is increased to 16 times its previous value, the percentage change in the de-Broglie wavelength of the particle is :
The angle of a prism is 'A'. One of its refracting surfaces is silvered. Light rays falling at an angle of incidence 2A on the first surface returns back through the same path after suffering reflection at the silvered surface. The refractive indexµ, of the prism is
Dependence of intensity of gravitational field (E) of earth with distance (r) from centre of earth is correctly represented by
If the focal length of objective lens is increased then magnifying power of:
A thin semicircular conducting ring (PQR) of radius 'r' is falling with its plane vertical in a horizontal magnetic field B, as shown in figure. The potential difference developed across the ring when its speed is v, is:
A thin semicircular conducting ring (PQR) of radius 'r'
In an ammeter 0.2% of main current passes through the galvanometer. If resistance of galvanometer is G, the resistance of ammeter will be:
A steady current flows in a long wire. It is bent into a circular loop of one turn and the magnetic field at the centre of the coil is $ B $ . If the same wire is bent into a circular loop of $ n $ turns, the magnetic field at the centre of the coil is
Two concentric hollow spherical shells have radii $ r $ and $ R \left(R\,>>\,r\right) $ . A charge $ Q $ is distributed on them such that the surface charge densities are equal. The electric potential at the centre is
A balloon with mass m is descending down with an acceleration a (where a < g). How much mass should be removed from it so that it starts moving up with an acceleration $a$?
When longitudinal wave propagates, what happens in the region of compressions and rarefactions?
A stone of mass $0.05 \,kg$ is thrown vertically upwards. What is the direction and magnitude of net force on the stone during its upward motion ?
Period of geostationary satellite is
The equivalent resistance of two resistors connected in series is $6\, \Omega$ and their parallel equivalent resistance is $\frac{4}{3} \Omega$. What are the values of resistances ?
One second is defined as
Einstein was awarded Nobel prize for his work in
On an average, a human heart is found to beat $72$ times a minute. Its frequency and period are
A proton and helium nucleus are shot into a magnetic field at right angles to the field with same kinetic energy. Then the ratio of their radii is
Which one of the following represents uniform motion ?
Find the energy equivalent of one atomic mass unit in joules and in $MeV$.
The ratio of $ \frac{C_P}{C_V}$ for a diatomic gas is
The mutual inductance between two coils depends upon
A concave mirror forms an enlarged, erect, virtual image of an object, only when the object is placed
The centre of mass of a system of two bodies of masses $M$ and $m, (M > m)1$ separated by a distance $d$ is
The photoelectric threshold for a certain metal is $3600\, \mathring A$. The maximum energy of the ejected photoelectrons by radiation of $2000\, \mathring A$ is (Given $h = 6.62 \times 10^{-34} J \, s$ )