Question

The MRI in a hospital scans with 400 MHz. How much energy does it correspond to(in kJ/mol) ?​

Answer 1

we know,

E = hC / λ

where c, the speed of light, is 2.998 x 10^8 m s–1.

1 MHz = 0.001 ms

400 MHz = 2.5 × 10^-6 ms = λ

h = plank's constant = 6.626 × 10^-34 j-s

put the values,

E = (6.626 × 10^-34 × 2.998 x 10^8 ) / (2.5 × 10^-6)

= 7.89 × 10^-20 kJ/mol (ans)