Light as a wave and as a particle
Grade 11 Science Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.
The CRC Handbook gives copper a work function of 4.7 eV. With hc = 1239.84 eV·nm, what is the longest wavelength that frees electrons, to 0.1 nm, Ari?
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?
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?
In a double-slit pattern, what makes a bright band, Jun?
- One slit being brighter
- Light bouncing off the screen
- Waves arriving in step
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
One of the two slits is covered. What happens to the bands, Luz?
- The bands go away
- They double in number
- They get sharper
Milo says bright enough red light will free electrons from any metal. Agree or disagree?
- Agree: brightness adds energy to each photon
- Agree: bright light works on any metal
- Disagree: red photons may be too weak
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: energy doubles with brightness
- Agree: brighter light gives faster electrons
Pia says the photoelectric effect proves light is never a wave. Agree or disagree?
- Agree: particles can't interfere
- Disagree: light also shows wave interference
- Agree: waves can't free electrons
Infrared photons of about 1 eV shine on cesium (2.1 eV). What happens, Zee?
- Electrons leave with 1.1 eV
- Electrons leave with 3.1 eV
- No electrons are freed