8. Choose the correct answer In the equation, Phi =Phi _(0)cdot e^-mu x for the initial X-ray flux attenuation in the substance , what quantity is represented by "mu " ? ) mass attenuation coefficient linear attenuation coefficient penetration depth linear Ionization Density

The correct answer is B) linear attenuation coefficient.<br /><br />In the given equation, $\Phi =\Phi _{0}\cdot e^{-\mu x}$, $\mu$ represents the linear attenuation coefficient. The linear attenuation coefficient is a measure of the attenuation of X-rays as they pass through a substance. It is defined as the fraction of X-rays that are attenuated per unit distance traveled in the substance. The linear attenuation coefficient is a dimensionless quantity and is typically expressed in units of cm$^{-1}$ or mm$^{-1}$.