Final answer:
The X-rays are largely absorbed by hard tissues such as bones when a high-intensity beam is used, appearing lighter on the X-ray image and enabling the visualization of structures with differing densities while minimizing exposure to radiation.
Step-by-step explanation:
When a high-intensity X-ray beam is used on an object such as a patient's hard tissues like bones, the X-rays are largely absorbed by these hard tissues. This process results in the creation of an image where hard tissues appear lighter on an X-ray plate because they block the X-rays, whereas soft tissues allow more X-rays to pass through and appear as gray. The X-rays produce a shadow image of the structures through which they pass. In dense materials, the depth of penetration is less, causing fewer X-ray photons to get through, and thus, a darker shadow is formed on the X-ray image. This ability of X-rays makes them invaluable in medicine for detecting fractures and observing physiological structures with differing densities. However, X-rays are a form of high energy radiation and are capable of ionizing materials, which can damage cells and potentially lead to cancer, so their use is carefully controlled to minimize any harmful biological effects.