JEE Physics - MCQ Practice Questions

The rest mass energy of an electron is approximately:

In photoelectric effect, the stopping potential V₀ for a metal is 2V. If the frequency of incident light is doubled, the new stopping potential will be:

The de Broglie wavelength of a particle is given by:

An electron transitions from n=3 to n=1 in a hydrogen atom. The frequency of emitted photon is (Use Rydberg constant R = 1.097×10⁷ m⁻¹):

The binding energy per nucleon is maximum for:

A radioactive nucleus has half-life of 10 days. After 30 days, the fraction of original nuclei remaining is:

The threshold frequency for a metal is f₀. If light of frequency 2f₀ is incident, the maximum kinetic energy of photoelectrons is:

Compton scattering demonstrates:

The energy of a photon in terms of wavelength is:

A charged particle is accelerated through a potential difference of 100V. Its de Broglie wavelength is λ₁. If accelerated through 400V, the wavelength becomes λ₂. The ratio λ₁/λ₂ is:

The activity of a radioactive sample decreases by 50% in 1 hour. Its half-life is:

The work function of a metal is 2.3 eV. The metal will exhibit photoelectric effect with light of wavelength:

In the Bohr model, the radius of nth orbit in a hydrogen atom is proportional to:

A 1 gram sample of a radioactive isotope with atomic mass 100 undergoes decay. Initial activity is 10¹⁵ Bq. The decay constant is approximately:

The energy of an α-particle in the ground state of hydrogen-like atom (Z=2) compared to ground state of hydrogen is:

The characteristic X-ray spectrum is produced due to:

According to Heisenberg's uncertainty principle, if the uncertainty in position (Δx) is zero, then uncertainty in momentum (Δp) will be:

An electron and a proton have the same kinetic energy. The ratio of their de Broglie wavelengths (λₑ/λₚ) is:

The pair production process requires a minimum photon energy of:

The ratio of specific charge (e/m) for an α-particle to that of a proton is: