An aluminium block is positioned close to a small source of X-ray radiation, as shown in Fig. 10.1. X-rays from the source are detected at point A and at point B. State two reasons why the intensity of the X-ray beam at point B is less than the intensity at point A.
Fig. 10.2 shows a cross-section of a finger model. The model thickness is $2.4\,\text{cm}$ and the thickness of the bone in the model is $1.1\,\text{cm}$. Parallel X-ray beams enter the model along the directions AB and CD, as shown in Fig. 10.2.
Calculate the ratio $$\frac{\text{intensity of X-ray beam incident on the model}}{\text{intensity of X-ray beam emergent from the model}}$$ for beam AB.
Calculate the ratio $$\frac{\text{intensity of X-ray beam incident on the model}}{\text{intensity of X-ray beam emergent from the model}}$$ for beam CD.
Use your answers in (b) to suggest why, for this model, an X-ray image may be obtained with good contrast.