Concept explainers
Why protons are used in MRI of body tissues rather than neutrons.
Answer to Problem 43.1DQ
Unlike free protons (
Explanation of Solution
The predominant components in any living body are organic molecules and water. The major content of these chemical entities are the hydrogen atoms or in other words the protons. Thus, the free proton content is huge enough to make proper response towards magnetic field and hence used in the MRI scanning.
However, in the case of neutrons, even though they have magnetic dipole moment and can undergo spin flip by absorbing electromagnetic radiation, they cannot be used in MRI. This is because there are virtually no free neutrons in the body and hence there will not be any proper response that can be expected due to neutrons, when a body tissue is subjected to the magnetic field of MRI.
Conclusion:
Therefore, unlike free protons (
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Chapter 43 Solutions
University Physics with Modern Physics, Volume 1 (Chs. 1-20) and Mastering Physics with Pearson eText & ValuePack Access Card (14th Edition)
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