CAIE A-Level Physics 22.1.4 The Electronvolt
Practise converting particle and photon energies between electronvolts and joules, comparing magnitudes and retaining the correct energy unit.
- Syllabus
- 2028–2030
- Course
- Physics 9702
- Level
- A2
Practise converting particle and photon energies between electronvolts and joules, comparing magnitudes and retaining the correct energy unit.
In an experiment, electromagnetic radiation of frequency f is incident on a metal surface.
The results in Fig. 10.1 show the variation with frequency f of the maximum kinetic energy EMAX of electrons emitted from the surface.

Fig. 10.1
The work function energy in eV for some metals is given in Table 10.1.

Table 10.1
Determine the metal used in the experiment. Show your working.
3.6×10−19/1.6×10−19=2.3eV so potassium
A1