JEE Main Physics: Modern Physics Practice Questions

14 questions with answers and step-by-step solutions. Tap any question to see the full worked solution.

  1. Q1.
    The energy of a photon with frequency nu is given by which of the following expressions?
    Easy
  2. Q2.
    What is the value of the work function for a metal surface if the threshold frequency is 5 times 10 to the power 14 Hertz?
    Easy
  3. Q3.
    In the Bohr model of the hydrogen atom, what is the angular momentum of an electron in the first orbit?
    Easy
  4. Q4.
    Which of the following particles has the longest de Broglie wavelength if they all move with the same velocity?
    Easy
  5. Q5.
    What is the half-life of a radioactive substance if its decay constant is 0.693 per second?
    Easy
  6. Q6.
    A radioactive sample has a half-life of 20 days. What fraction of the original sample will remain undecayed after 100 days?
    Medium
  7. Q7.
    In a photoelectric effect experiment, the stopping potential for a metal surface is 2.0 V when light of wavelength 300 nm is used. What is the work function of
    Medium
  8. Q8.
    An electron in a hydrogen atom jumps from the third excited state to the ground state. What is the wavelength of the emitted photon?
    Medium
  9. Q9.
    The de Broglie wavelength of an electron accelerated through a potential difference of 100 V is approximately:
    Medium
  10. Q10.
    A nucleus with mass number 240 breaks into two fragments each of mass number 120. If the binding energy per nucleon of the parent nucleus is 7.6 MeV and that of
    Medium
  11. Q11.
    A hydrogen-like atom with atomic number Z is in an excited state of principal quantum number n. It emits a photon of wavelength lambda when it transitions to th
    Hard
  12. Q12.
    A radioactive sample decays with a decay constant lambda. The time required for the activity to decrease from A0 to A0/e is t1, and the time required for the nu
    Hard
  13. Q13.
    An electron in a hydrogen atom makes a transition from the n=3 state to the n=1 state. The recoil velocity of the hydrogen atom is approximately given by which
    Hard
  14. Q14.
    A particle of mass m is confined in a one-dimensional box of length L. The energy difference between the first excited state and the ground state is Delta E. If
    Hard

Track your progress on Modern Physics

Sign up free to attempt these questions, score yourself, and see which topics need work.

Start Practising Free →
Modern Physics — JEE Main Physics Practice Questions with Solutions | SolveGini