What is the frequency (in Hz) and wavelength (in m) of this gamma ray?

Question

Cobalt-60 is a radioactive isotope used to treat cancers of the brain and other tissues. A gamma ray emitted by an atom of this isotope has an energy of 1.33 MeV (million electron volts; 1 eV = 1.602 10-19 J). What is the frequency (in Hz) and wavelength (in m) of this gamma ray?
frequency
Hz
wavelength
m

Answer 1

Please remember the formula between the energy and frequency or wavelength:
E = hν = hc/λ
where E the energy in J, h the Plank constant 6.626x10^-34 J•s, ν the frequency in 1/s or Hz, c the speed of light 2.998x10^8 m/s, and λ the wavelength in m. Therefore:
ν = E/h = (1.33e6*1.602e-19 J)/(6.626e-34 J•s)
= 3.22x10^20 Hz
λ = c/ν = (2.998e8 m/s)/(3.22x10^20/s)
= 9.32x10^-13 (m)