DP Physics (last assessment 2024)
Question 20N.3.HL.TZ0.17a
| Date | November 2020 | Marks available | [Maximum mark: 3] | Reference code | 20N.3.HL.TZ0.17a |
| Level | HL | Paper | 3 | Time zone | TZ0 |
| Command term | Explain | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 3]
20N.3.HL.TZ0.17a
The photograph shows an X-ray image of a hand.
© International Baccalaureate Organization 2020.
(a)
Explain how attenuation causes the contrast between soft tissue and bone in the image.
[3]
Markscheme
bone «denser so» absorb rays «and appear white in the negative» ✓
larger attenuation for bone ✓
muscles have less attenuation, so rays pass through «and appear darker» ✓
Accept the reversed argument
Examiners report
Candidates successfully answered in terms of absorption and managed to score two marks but not all of them.
