To penetrate a thicker or denser material, what is required from the source?

To penetrate thicker or denser materials, a source of radiation must emit particles or waves with more energy. Higher energy radiation has greater penetrating power due to its ability to overcome the binding energy of atoms in the material. This means it can effectively interact with the atomic structures of the material, allowing it to pass through without being absorbed or scattered.

In contrast, options suggesting less energy or a longer wavelength would imply a decrease in penetration capability. A longer wavelength corresponds to lower energy, which would be insufficient to pass through dense materials effectively. More mass by itself doesn’t directly relate to the energy needed for penetration; rather, it is the energetic properties of the radiation that determine its penetrating ability. Thus, for effective penetration, increased energy is essential.