DP Physics (last assessment 2024)

Test builder »

Question 19N.3.HL.TZ0.14b

Select a Test
Date November 2019 Marks available [Maximum mark: 3] Reference code 19N.3.HL.TZ0.14b
Level HL Paper 3 Time zone TZ0
Command term Outline Question number b Adapted from N/A
b.
[Maximum mark: 3]
19N.3.HL.TZ0.14b
(b)

In nuclear magnetic resonance (NMR) protons inside a patient are made to emit a radio frequency electromagnetic radiation. Outline the mechanism by which this radiation is emitted by the protons.

[3]

Markscheme

«a uniform» magnetic field is applied to align proton spins ✔

proton spins are excited by an «external» radio frequency signal/field
OR
protons change from spin-up to spin-down state due to «external» RF signal/field ✔

«radio frequency» radiation is emitted as the protons relax ✔

 

NOTE: For MP3 do not allow simplistic “protons emit RF radiation” as this is given in the question

Syllabus sections