What term describes energy that is radiated or transmitted in the form of rays or waves or particles?

• A. Radiation
• B. Conduction
• C. Convection
• D. Reflection

Answer: (A)

Energy moving through space away from its source as rays, waves, or particles is described as radiation. This includes electromagnetic waves like light and radio waves, which can travel through empty space, as well as particle radiation such as alpha or beta particles. The key idea is that radiation does not require a medium to transfer energy; it can move through a vacuum.

Conduction, by contrast, passes energy through direct contact within and between materials, relying on the material’s ability to transfer kinetic energy. Convection transfers energy via the movement of fluids, carrying heat with circulating currents. Reflection involves waves changing direction when they hit a boundary, but it doesn’t describe the mechanism of energy transfer across space.