List of top Physics Questions

In shown fig, the circular loop of wire is moved with velocity towards the infinite current carrying wire. Then

For a current carrying inductor, emf associated is 20mV. Now, current through it changes from 6A to 2A in 2s. The coefficient of mutual inductance is

The wavelength of an electron for transition from a state \(n_1\) to \(n_2\) is \( \frac{9}{8R} \). Which of the following wavelengths is possible for a transition from \(n_2\) to \(n_1\)?

Holography is based on phenomenon of

A square current carrying loop is changed to a circular loop in time \( t_1 \). Then

The potential energy of a system increases if work is done

In Wheatstone bridge, 4 resistors \( P = 10 \, \Omega \), \( Q = 5 \, \Omega \), \( R = 4 \, \Omega \), \( S = 4 \, \Omega \) are connected in cyclic order. To ensure no current through galvanometer,

In photoelectric effect, initially when energy of electrons emitted is \( E_0 \), de-Broglie wavelength associated with them is \( \lambda_0 \). Now, energy is doubled then associated de-Broglie wavelength \( \lambda' \) is

In given circuit, \( C_1 = C_2 = C_3 = C \) initially. Now, a dielectric slab of dielectric constant \( K = \frac{3}{2} \) is inserted in \( C_2 \). The equivalent capacitance becomes

A proton and an electron are placed in a uniform electric field. Which of the following is correct?

A long string with a charge of a per unit length passes through an imaginary cube of edge L.
The maximum possible flux of electric field through the cube will be

A string of length $\ell$ is fixed at both ends. It is vibrating in its $3^{rd}$ overtone with maximum amplitude '$a$'. The amplitude at a distance $\ell /3$ from one end is.

The given circuit has two ideal diodes connected as shown in the figure below. The current flowing through the resistance \(R_1\) will be

A resistor of resistance $R$, capacitor of capacitance $C$ and inductor of inductance $L$ are connected in parallel to $A C$ power source of voltage $\epsilon_{0} \sin \omega_{t}$. The maximum current through the resistance is half of the maximum current through the power source. Then value of $R$ is

Two identical charged spheres suspended from a common point by two massless strings of lengths $l$, are initially at a distance $d(d < < l)$ apart because of their mutual repulsion. The charges begin to leak from both the spheres at a constant rate. As a result, the spheres approach each other with a velocity $v$. Then $v$ varies as a function of the distance $x$ between the spheres, as:

A source of sound $S$ emitting waves of frequency $100\, Hz$ and an observor $O$ are located at some distance from each other. The source is moving with a speed of $19.4\, m s^{-1}$ at an angle of $60^{\circ}$ with the source observer line as shown in the figure. The observor is at rest. The apparent frequency observed by the observer is (velocity of sound in air $330\, ms ^{-1}$ )

For the angle of minimum deviation of a prism to be equal to its refracting angle, the prism must be made of a material whose refractive index :

A deuteron of kinetic energy $50 \,keV$ is describing a circular orbit of radius $0.5$ metre in a plane perpendicular to the magnetic field $B$. The kinetic energy of the proton that describes a circular orbit of radius $0.5$ metre in the same plane with the same $B$ is

Find the number of photon emitted per second by a $25$ watt source of monochromatic light of wavelength $ 6600\, ??. What is the photoelectric current assuming $3\%$ efficiency for photoelectric effect ?

Kepler's third law states that square of period of revolution $(T)$ of a planet around the sun, is proportional to third power of average distance $r$ between sun and planet i.e. $T^{2}=K r^{3}$ here $K$ is constant. If the masses of sun and planet are $M$ and $m$ respectively then as per Newton's law of gravitation force of attraction between them is $F=\frac{G M m}{r^{2}}$ here $G$ is gravitational constant. The relation between $G$ and $K$ is described as

The approximate depth of an ocean is $2700\, m$. The compressibility of water is $45.4 \times 10^{-11} Pa ^{-1}$ and density of water is $10^{3} kg / m 3 .$ What fractional compression of water will be obtained at the bottom of the ocean?

Two spheres of different materials one with double the radius and one-fourth wall thickness of the other are filled with ice. If the time taken for complete melting of ice in the larger sphere is $25$ minute and for smaller one is $16$ minute, the ratio of thermal conductivities of the materials of larger spheres to that of smaller sphere is

The magnetic moment of atomic neon (in units of Bohr's magnetron) is