(a(i))[2]
State what the hardness of an X-ray beam means.
(a(ii))[1]
State how the hardness of an X-ray beam produced by an X-ray tube is increased.
(b)[2]
The same parallel beam of X-ray radiation is sent, separately, through samples of bone and of muscle. The thickness $x$ of the bone and muscle samples, along with the linear attenuation (absorption) coefficients $\mu$ of the radiation in bone and in muscle, are shown in Fig. 10.1. Find the ratio \[ \frac{\text{intensity transmitted through bone}}{\text{intensity transmitted through muscle}}. \]