What is the definition of radiation?

The definition of radiation is accurately described as energy that is radiated or transmitted in the form of rays, waves, or particles. This encompasses a broad range of energy types, including electromagnetic radiation such as light and radio waves, as well as particle radiation like alpha and beta particles. This understanding is fundamental in various fields, particularly in physics and medical technologies, including laser practices, where understanding how energy travels is crucial.

Other options present misconceptions. Energy absorbed by materials pertains to different phenomena, such as conduction and absorption, rather than the inherent nature of radiation itself. The idea that radiation only travels in solid forms is incorrect; radiation can travel through various mediums, including gases and vacuums. Lastly, defining radiation solely as energy that can be felt as heat oversimplifies the concept and neglects other forms of radiation that may not produce heat sensations, such as visible light. Overall, recognizing radiation as a broad category of energy transmitted through various forms is essential for a comprehensive understanding.