DP Physics (first assessment 2025)
Question 20N.2.HL.TZ0.10b(iii)
| Date | November 2020 | Marks available | [Maximum mark: 2] | Reference code | 20N.2.HL.TZ0.10b(iii) |
| Level | HL | Paper | 2 | Time zone | TZ0 |
| Command term | Outline | Question number | b(iii) | Adapted from | N/A |
b(iii).
[Maximum mark: 2]
20N.2.HL.TZ0.10b(iii)
(b(iii))
Outline why electrons with energy of approximately would be unsuitable for the investigation of nuclear radii.
[2]
Markscheme
the de Broglie wavelength of electrons is «much» longer than the size of a nucleus ✓
hence electrons would not undergo diffraction
OR
no diffraction pattern would be observed ✓
Examiners report
Candidates generally scored poorly on this question. There was confusion between this experiment and another diffraction one, so often the new wavelength was compared to the spacing between atoms. Also, in line with answers to b(i) there were suggestions that the electrons did not have sufficient energy to reach the nucleus or would be deflected by too great an angle to be seen.
