A patient is placed in an MRI machine and as the MRI is taken the magnetic field

Question

A patient is placed in an MRI machine and as the MRI is taken the magnetic field level with the patients eyes is 1.5 T. The magnetic field is largest at the persons head and the field gradient in the machine is 0.05 T/m. The patients heart is located 30 cm below their eyes, the patients liver is located 60 cm below their eyes, and the patients bladder is located 70 cm below their eyes.

Assuming the magnetic field gradient remains constant across the whole body, what is the Larmor frequency at the patients eyes, their liver, and their bladder (in MHz)?

THIS IS NOT THE QUESTION I WANT ANSWERED. IT IS ONLY USED AS A REFERENCE FOR MY ACTUAL QUESTION.

The MRI apparatus in the previous question can distinguish between signals whose frequencies differ by just 0.005 MHz. What is the resolution of this machine along the person's body? (ACTUAL QUESTION)

Explanation / Answer

f = qB / [2*pi*m] ;

given B at eyes is 1.5 T

mp = 9.1*10-31 kg; q = 1.6*10-19 C;

f = 1.6*10-19 *1.5T/ [2*pi*9.1*10-31 kg]

lamour frequency at the patients eyes is feyes = 22.84 MHz

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