Lesson 4.5.1

4.5.1 Photons Quiz: OCR Physics, Unit 3

20 questions

Written by Revision Ninja · Last reviewed 11 October 2026

In partnership with Revision Ninja

Lesson 4.5.1, Photons: 20 multiple choice questions for the OCR Physics (H156), Unit 3: Electrons, waves and photons, written with Revision Ninja.

Host it live on the board and students join with a game code on their own devices, or revise alone with Free Play. The answers are revealed in the game.

Host this setFree Play

The 20 questions

  1. In the photon model, electromagnetic radiation is made up of discrete packets of energy called:

    • electrons
    • phonons
    • photons
    • protons

  2. A photon has a frequency of 5.0 x 10^14 Hz. Using h = 6.6 x 10^-34 J s, what is its energy?

    • 3.3 x 10^-20 J
    • 1.3 x 10^33 J
    • 3.3 x 10^-19 J
    • 7.6 x 10^-49 J

  3. What is the energy of a photon of wavelength 500 nm? Use c = 3.0 x 10^8 m/s and h = 6.6 x 10^-34 J s.

    • 6.0 x 10^-26 J
    • 2.5 x 10^-40 J
    • 4.0 x 10^-13 J
    • 4.0 x 10^-19 J

  4. One electronvolt expressed in joules is approximately:

    • 1.6 x 10^-19 J
    • 1.0 x 10^19 J
    • 1.6 x 10^-17 J
    • 6.6 x 10^-34 J

  5. The electronvolt (eV) is a unit of:

    • frequency
    • charge
    • energy
    • power

  6. The unit of the Planck constant h is:

    • W/Hz^2
    • J m
    • J s
    • J/s^2

  7. Increasing the intensity of monochromatic light increases which property of the light?

    • Photon energy
    • Photon arrival rate
    • Photon frequency
    • Photon speed

  8. A photon has energy 2.0 eV. What is this energy in joules?

    • 1.2 x 10^-19 J
    • 3.2 x 10^-19 J
    • 2.0 x 10^-19 J
    • 6.4 x 10^-19 J

  9. Which value of the product hc is used when photon energy is in eV and wavelength in nm?

    • 1.6 eV nm
    • 3.0 eV nm
    • 1240 eV nm
    • 6.6 eV nm

  10. An LED emits light of wavelength 650 nm. Using eV = hc/lambda, what is the minimum voltage to switch it on?

    • 1.9 V
    • 0.52 V
    • 3.4 V
    • 650 V

  11. When plotting threshold voltage against frequency for different coloured LEDs, the gradient of the straight line gives:

    • he
    • e/h
    • h/e
    • hc

  12. Which photon carries greater energy, a blue photon or a red photon?

    • Both carry equal
    • The red photon
    • The blue photon
    • Neither carries energy

  13. A 1.0 mW laser emits light of wavelength 600 nm. Approximately how many photons are emitted per second?

    • 3.0 x 10^12 per s
    • 3.3 x 10^-19 per s
    • 3.0 x 10^15 per s
    • 6.0 x 10^17 per s

  14. A 500 nm photon compared with an X-ray photon of wavelength 1.0 nm has energy that is how many times smaller?

    • 1/5 times
    • 5 times
    • 500 times
    • 500 times larger

  15. A photon has energy 4.0 eV. What is its frequency? Use h = 6.6 x 10^-34 J s and 1 eV = 1.6 x 10^-19 J.

    • 6.6 x 10^-34 Hz
    • 1.2 x 10^6 Hz
    • 9.7 x 10^14 Hz
    • 2.7 x 10^33 Hz

  16. If the frequency of a photon doubles, its energy:

    • doubles
    • halves
    • stays the same
    • quadruples

  17. An electron is accelerated through a potential difference of 5.0 kV. What kinetic energy does it gain?

    • 5.0 keV
    • 0.005 keV
    • 5.0 MeV
    • 5.0 eV

  18. Using hc = 1240 eV nm, what is the energy of a photon of wavelength 620 nm?

    • 4.0 eV
    • 0.5 eV
    • 2.0 eV
    • 1.2 eV

  19. The Planck constant expressed in eV s is approximately:

    • 6.6 x 10^-34 eV s
    • 4.1 x 10^-15 eV s
    • 3.0 x 10^8 eV s
    • 1.6 x 10^-19 eV s

  20. A laser emits light of frequency 6.0 x 10^14 Hz with power 2.0 mW. About how many photons are emitted per second?

    • 8.0 x 10^11
    • 1.2 x 10^18
    • 5.0 x 10^15
    • 2.0 x 10^-3

All OCR Physics quizzes