List of top Physics Questions

The refractive index of a medium is \(\sqrt{3}\). The angle of incidence for which the angle of refraction is \(30^\circ\) is:
The Fermi level in an intrinsic semiconductor lies:
A Carnot engine operates between 400 K and 300 K. Its efficiency is:
The binding energy per nucleon is maximum for:
In Young's double-slit experiment, the slits are 0.2 mm apart and the screen is 1 m away. The distance between the central bright fringe and the third bright fringe is 1.5 cm. The wavelength of light used is:
The moment of inertia of a thin ring about its diameter is:
Two point charges \(+q\) and \(-q\) are placed at distance \(2a\) apart. The electric field intensity is zero at a point on the axis at distance \(x\) from the midpoint. Then \(x\) is:
The activity of a radioactive sample decreases to 25% of its initial value in 60 days. The half-life is:
A sound wave has frequency 500 Hz and wavelength 0.68 m. The speed of sound is:
A body weighs 50 N on the surface of Earth. Its weight at a height equal to the radius of Earth from the surface is:
The potential energy of a particle of mass 2 kg moving along x-axis is given by \(U = (x^2 - 4x)\) J. The force acting on it at \(x = 3\) m is:
A transformer has 500 turns in primary and 100 turns in secondary. If input voltage is 220 V AC, the output voltage is:
Light of wavelength 600 nm is incident on a metal surface with work function 2 eV. The maximum kinetic energy of photoelectrons is:
A stone is dropped from a height of 80 m. At the same instant, another stone is projected vertically upwards from the ground with a speed of 40 m/s. The time after which they meet is (\(g = 10\ \text{m/s}^2\)):
A charged particle enters a uniform magnetic field perpendicular to its velocity. If the field is suddenly doubled, the radius of its path becomes:
The de Broglie wavelength of an electron accelerated through 100 V is approximately:
A uniform rod of length \(L\) and mass \(M\) is pivoted at one end and displaced by a small angle \(\theta\) from vertical. The time period of small oscillations is:
In a series LCR circuit at resonance, the voltage across the inductor is 100 V and across the capacitor is 100 V. The voltage across the resistor is:
A particle moves with uniform acceleration along a straight line. The average velocity over an interval is equal to the instantaneous velocity at:
The work done by a conservative force in a closed path is:
The unit of electric field intensity is:
In a p-n junction diode, the reverse saturation current doubles for every rise in temperature of:
The half-life of a radioactive element is 8 days. The fraction remaining after 32 days is:
A convex lens of focal length 20 cm forms a real image at 30 cm from the lens. The object distance is:
The escape velocity from the surface of Earth is 11.2 km/s. If the radius of Earth is doubled and mass remains the same, the new escape velocity will be: