Which type of radiation has the highest energy and can penetrate most materials?

Gamma rays are a form of electromagnetic radiation with extremely high energy and very short wavelengths. This combination allows gamma rays to penetrate most materials, including human tissue and various dense substances like lead and concrete, making them significantly more penetrating than other types of radiation, such as alpha and beta rays.

Alpha rays are composed of heavy particles that have a positive charge and can be stopped by just a sheet of paper or even human skin. Beta rays consist of lighter electrons or positrons and can penetrate further than alpha rays but are still stopped by materials like plastic or glass. X-rays, while also high energy, are less penetrating than gamma rays and are typically absorbed by denser materials more effectively.

The ability of gamma rays to penetrate materials is why they are of particular interest in fields like medicine and astrophysics, where their detection can provide valuable information about high-energy processes and structures in the universe.