essay An MRI essentially detects Hatoms by looking at radio

(essay) An MRI essentially detects H-atoms by looking at radio wave absorption and re-emission. Why are such strong magnetic fields necessary? Under what conditions would an H-atom within this strong magnetic field absorb a radio wave and what about the H-atom changes when this absorption occurs?

Solution

Ans) Such a strong magnetic field necessary because a strong magnetic field reduces the energy difference between a spin that is aligned and anti-aligned with the magnetic field.

Energy from an oscillating magnetic field is temporarily applied to the patient at the appropriate resonance frequency. The excited hydrogen atoms emit a radio frequency signal which is measured by receiving coil.

If the body absorbs the energy heating occurs.