Photons, Photoelectric Effect & Wave–Particle Models — Drills · Grade 12 Science
Chapter: Modern PhysicsWhat these drills covers
By the end of Photons, Photoelectric Effect & Wave–Particle Models you should be able to:
- I can explain threshold and intensity evidence for photoelectric emission.
- I can calculate photon energy, maximum electron energy, and stopping potential.
2 questions, numeric and written answer, each with a worked explanation.
Vocabulary used: work function, threshold frequency, electronvolt.
Problem 1
Photon 5 eV, work function 2 eV. Find Kmax.
Hints
Write the relationship first; substitute with consistent units.
Answer and explanation
3 eV
5−2=3.
Problem 2
Why does brighter below-threshold light not eject electrons in the basic model?
Answer and explanation
Each photon lacks the required energy; adding more such photons does not change the single-photon energy.
Response criteria
- State a scientifically accurate conclusion.
- Show the calculation or mechanism that supports it.
- Include units, conditions, or limits where relevant.