Medical X-rays used for CT (computed tomography) scans have a frequency of _____

ID: 1465976 • Letter: M

Question

Medical X-rays used for CT (computed tomography) scans have a frequency of ______Hz.

Calculate the following properties of these X-rays:

a) The wavelength in vacuum, and in the patient’s body (assume that the human body has an average refractive index the same as glycerin).

b) The period and angular frequency of these X-rays.

c) If the average power delivered by such an X-ray beam on a surface of ____mm2 is ____W, calculate the intensity of this X-ray beam.

Solve using variables, rather than numbers.

so now

part A : Wavelength , frequency f and Velocity of light c are related as c = Lf

also L depends on refractive index n as n = c/v = L/Lo

Wavelength Lo in air = c/f = 3 e8/5 e18 = 6 e -11 m

refractive index of glycerin, n = 1.474

so Wavelength new = L new = Lo/n = 6 e-11/(1.474)

Lnew = 4.07 e -11 m

part B : time period T = 1/frequency

T = 1/5e 18 = 2 e-19 secs

angular frequency, w = 2 pi f = 2*3.14 * 5 e 18 = 3.14*10^19 rad/s

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c) Intensity = power/Area