Question

A broken leg with a mass of 5kg receives an equivalent dose of 0.5mSv. If the X-ray energy is 50keV,how many x-ray photons were absorbed?

Answer 1

D_T.R = $\frac{H_T}{w_R}=\frac{0.5\times10^{-3}}{1} = 0.5\times10^{-3} Gy$

$\epsilon_T = D_Tm_T = (0.5\times10^{-3}Gy)(5 kg) = 2.5\times10^{-3} J$

N = $\frac{\epsilon_T}{E_{photon}} = \frac{2.5\times10^{-3}J}{(50\times10^{-3}MeV)(1.602\times10^{-13}\frac{J}{MeV})}= 3.12\times 10^{11}$

Answer: N = 3.12$\times$10¹¹.