List of top Physics Questions

In a nuclear reactor, the fuel is consumed at the rate of \( 1 \times 10^{-3} \) gs\(^{-1}\). The power generated in kW is:
In the diodes shown in the diagrams, which one is reverse biased?
The following configuration of gates is equivalent to:
configuration of gates
An alternating current is given by \( i = (3 \sin \omega t + 4 \cos \omega t) \) A. The rms current will be:
Energy levels A, B, and C of a certain atom correspond to increasing values of energy, i.e., \( E_A<E_B<E_C \). If \( \lambda_1, \lambda_2, \) and \( \lambda_3 \) are the wavelengths of a photon corresponding to the transitions shown, then:
Energy levels A, B, and C
A charge ‘q’ is spread uniformly over an isolated ring of radius ‘R’. The ring is rotated about its natural axis with angular speed \( \omega \). The magnetic dipole moment of the ring is:
The frequency of fifth harmonic of a closed pipe is equal to the frequency of third harmonic of an open pipe. If the length of the open pipe is 72 cm, then the length of the closed pipe is:
The ratio of the molar specific heat capacities of monatomic and diatomic gases at constant pressure is:
A gas absorbs 18 J of heat and work done on the gas is 12 J. Then the change in internal energy of the gas is:
A particle of mass \( m \) at rest on a rough horizontal surface with a coefficient of friction \( \mu \) is given a velocity \( u \). The average power imparted by friction before it stops is:
As shown in the figure, two blocks of masses \(m_1\) and \(m_2\) are connected to a spring of force constant \(k\). The blocks are slightly displaced in opposite directions to \(x_1, x_2\) distances and released. If the system executes simple harmonic motion, then the frequency of oscillation of the system (\(\omega\)) is:
twoblocksofmassesm1andm2
The moment of inertia of a solid sphere about its diameter is 20 kg m². The moment of inertia of a thin spherical shell having the same mass and radius about its diameter is:
A person walks up a stalled escalator in 90s. When standing on the same moving escalator, he reached in 60s. The time it would take him to walk up the moving escalator will be:
Three logic gates are connected as shown in the figure. If the inputs are \( A = 0 \), \( B = 1 \), and \( C = 1 \), then the values of \( y_1 \), \( y_2 \), and \( y_3 \) are respectively:
logic gates
The power gain of a transistor operating in common emitter configuration is 32,000. If the input and output resistances of the circuit are 1200 \( \Omega \) and 6000 \( \Omega \) respectively, then the current gain is:
If two linear antennas having lengths in the ratio 2:3 are emitting radiations of wavelengths in the ratio 8:9, then the ratio of effective powers radiated by them are in the ratio:
Two photons of energies 2.5 eV and 5.5 eV incident on a metal surface of work function 1.5 eV. The ratio of the maximum speeds of the photoelectrons emitted from the metal surface is:
In a nuclear reactor of efficiency 25%, the number of fissions taking place per second is \( 5 \times 10^{13} \). If 200 MeV energy is released per fission, then the output power of the reactor is:
In a radioactive sample \( 2 \times 10^8 \) nuclei reduce to \( 10^8 \) nuclei in 15 minutes, then the half-life of the sample in minutes is:
Two equal resistances are connected in the two gaps of a meter bridge. If the resistance in the right gap is doubled, then the change in the balancing length is:
The quality factor of a series LCR resonant circuit is 75. If the resistance is decreased by 50% and the inductance is increased by 100%, then the quality factor of the circuit is:
A current \( i \) flows through a circular loop of radius \( R \). The ratio of the magnetic field produced at its centre to the field produced at a point at a distance \( \frac{R}{\sqrt{3}} \) from its centre on its axis is:
Two particles of charges in the ratio \( 1:2 \) and masses in the ratio \( 2:3 \) moving along a straight line enter a uniform magnetic field at right angles to the direction of the field. If the radii of the circular paths of the particles in the magnetic field are in the ratio \( 3:4 \), then the ratio of the initial linear momenta of the two particles is:
Magnetic field on the axis of a short bar magnet of magnetic moment \( M \), at a distance \( x \) from its centre is:
The ratio between electric field energy density and magnetic field energy density of an electromagnetic wave, in its region is: