1_Introduction to Medical Imaging (1)

Introduction to Medical Imaging – Chapter 1
Radiation and the Atom – Chapter 2
17-Feb-20
Raphex 2001 Question: EM Radiation
G52. Which of the following has the longest wavelength?
A. Radio waves
B. Visible light
C. Ultraviolet
D. X-rays
E. Gamma rays
35
35
Raphex 2002 Question: EM Radiation
G51. Visible light has a wavelength of about 6 x 10 -7 m.
60
Co gammas have a wavelength of 10 -12 m and an
energy of 1.2 MeV. The approximate energy of visible
light is:
A. 720 MeV
B. 72 keV
C. 2 eV
D. 7.2 x 10 -4 eV
E. 2 x 10 -6 eV
E 1 = hc/l 1 and E 2 = hc/l 2 , so E 1 l 1 = hc = E 2 l 2
E 2 = E 1 l 1 /l 2 = (12 x 10 5 eV)(10 -12 m)/(6 x 10 -7 m) = 2 eV
36
36
BME HCMUT 18