| Date | May 2012 | Marks available | 3 | Reference code | 12M.3.HL.TZ1.15 |
| Level | Higher level | Paper | Paper 3 | Time zone | Time zone 1 |
| Command term | Calculate, Explain, and State | Question number | 15 | Adapted from | N/A |
Question
This question is about ultrasonic imaging.
The table gives the velocity of sound in, and the densities of, the materials.
(i) State the SI unit for acoustic impedance.
(ii) Calculate the acoustic impedance for each material and write your answers in the table above.
Markscheme
(i) kgm–2s–1;
Award [2] for all correct and [1 max] for 2 or 1 correct.
Examiners report
[N/A]
Syllabus sections
Option C: Imaging » Option C: Imaging (Additional higher level option topics) » C.4 – Medical imaging (HL only)
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