DP Physics (last assessment 2024)
Question 18N.3.HL.TZ0.b
Date | November 2018 | Marks available | [Maximum mark: 2] | Reference code | 18N.3.HL.TZ0.b |
Level | HL | Paper | 3 | Time zone | TZ0 |
Command term | Outline | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 2]
18N.3.HL.TZ0.b
In nuclear magnetic resonance imaging (NMR) a patient is exposed to a strong external magnetic field so that the spin of the protons in the body align parallel or antiparallel to the magnetic field. A pulse of a radio frequency (RF) electromagnetic wave is then directed at the patient.
Outline the measurement that needs to be made after the RF signal is turned off.
[2]
Markscheme
Relaxation time «of signal/proton spin» ✔
Location/time delay of the emitted RF signal ✔
