Suggest two reasons for the loss of sharpness in an X-ray image.
A sheet of metal is tested with a parallel X-ray beam, as shown in Fig. 12.1. One part of the beam travels normally through metal of thickness $3.2\,\text{mm}$. A second part travels normally through metal of thickness $x\,\text{mm}$. The linear attenuation (absorption) coefficient for the X-ray beam in the metal is $1.5\,\text{cm}^{-1}$. The ratio of the intensity of X-ray beam transmitted through $3.2\,\text{mm}$ of metal to the intensity of X-ray beam transmitted through $x\,\text{mm}$ of metal is measured to be $0.81$. Calculate $x$.
A sheet of metal is tested with a parallel X-ray beam, as shown in Fig. 12.1. One part of the beam passes normally through metal of thickness $3.2\,\text{mm}$. Another part passes normally through metal of thickness $x\,\text{mm}$. The linear attenuation (absorption) coefficient for the X-ray beam in the metal is $1.5\,\text{cm}^{-1}$. The ratio \[ \frac{\text{intensity of X-ray beam passing through }3.2\,\text{mm of metal}}{\text{intensity of X-ray beam passing through }x\,\text{mm of metal}} \] is measured to be $0.81$.
The intensity ratio is equally the power ratio for the X-ray beams. Calculate this ratio in decibels.