PencilGo

Grade 11 · Science · Physics

11th grade Light as a wave and as a particle worksheet

6 printable versionsChallenge Me10 questions · answer keyFree · no account

Level: Building Confidence · On Level · Challenge Me

When it’s done, scan the sheet with your phone and PencilGo marks it and picks the next one. Create a free account

Version
Print

Light as a wave and as a particle

Grade 11 Science Worksheet - Challenge Me

NameDate

Circle the best answer, or write your answer on the line.

  1. The CRC Handbook gives sodium a work function of 2.28 eV. With hc = 1239.84 eV·nm, what is the longest wavelength that frees electrons, to 0.1 nm, Bo?

  2. The CRC Handbook gives magnesium a work function of 3.68 eV. With hc = 1239.84 eV·nm, what is the longest wavelength that frees electrons, to 0.1 nm, Esme?

  3. In a double-slit pattern, what makes a bright band, Jun?

    • Waves arriving in step
    • One slit being brighter
    • Light bouncing off the screen
  4. Very dim light sends photons through two slits one at a time. What builds up on the screen over time, Kira?

    • An even glow
    • Two plain bright lines
    • The same bright and dark bands
  5. One of the two slits is covered. What happens to the bands, Luz?

    • They double in number
    • The bands go away
    • They get sharper
  6. Noah says doubling the brightness of light on cesium doubles each electron's greatest energy. Agree or disagree?

    • Disagree: it doubles the number of electrons
    • Agree: brighter light gives faster electrons
    • Agree: energy doubles with brightness
  7. Pia says the photoelectric effect proves light is never a wave. Agree or disagree?

    • Disagree: light also shows wave interference
    • Agree: particles can't interfere
    • Agree: waves can't free electrons
  8. Ultraviolet light of 250 nm shines on copper (work function 4.7 eV). Are electrons freed, Ren?

    • No: copper can't free electrons
    • No: 250 nm is too long
    • Yes: each carries about 4.96 eV
  9. Light of 300 nm and light of 600 nm are compared. How do their photon energies compare, Tala?

    • They are equal
    • The 300 nm photons carry twice as much
    • The 600 nm photons carry twice as much
  10. Infrared photons of about 1 eV shine on cesium (2.1 eV). What happens, Zee?

    • Electrons leave with 3.1 eV
    • No electrons are freed
    • Electrons leave with 1.1 eV
PencilGopencilgo.com

11th grade Light as a wave and as a particle worksheet – printable
Print: 123456

About this worksheet

Light as a wave and as a particle. Every version has 10 questions, and the answer key prints on the second page.

What your child will learn

  • I can find a photon's energy from E = hc ÷ λ, with hc = 1239.84 eV·nm, and say that shorter waves carry more energy per photon.
  • I can use the photoelectric equation: greatest KE = hf − work function. Brighter light frees more electrons, not faster ones; below the threshold no electrons leave.
  • I can find a metal's threshold wavelength, λ = hc ÷ work function.
  • I can say which evidence supports each model: double-slit interference (wave) and the photoelectric effect (photon). Light shows both.

Standard: HS-PS4-3

Words to know

photon: One packet (quantum) of light energy

electronvolt (eV): A tiny energy unit: 1.602 176 634 × 10⁻¹⁹ J

work function: The least energy needed to free an electron from a metal

threshold: The lowest frequency (longest wavelength) that still frees electrons

interference: Waves adding to make bright bands or cancelling to make dark ones

Common mistakes

Your child divided the wrong way. A photon's energy is hc ÷ λ: shorter waves carry more energy.

Your child added the work function. Some of the photon's energy is used to free the electron, so subtract it.

Your child multiplied. The longest wavelength that still frees electrons is hc ÷ work function.

Questions parents ask

What is the most common mistake with light as a wave and as a particle?

Your child divided the wrong way. A photon's energy is hc ÷ λ: shorter waves carry more energy.

Are these 11th grade science worksheets free to print?

Yes. All 6 printable versions at each level are free to print, with the answer key, and no account is needed.

More physics

See all Physics

Every sheet you scan goes into your child’s record: dated, marked and ready for the year-end portfolio. Homeschool records