•Something that “radiates”, or
spreads out in “rays”
•
•High speed
particles (eg. high speed neutrons ejected
from a disintegrating atomic nucleus)
•
•Electromagnetic radiation:
–Towards shorter “wavelength” and
higher energy:
•Visible light, Ultraviolet light, X-Rays,
Gamma-Rays
–Towards longer “wavelength” and
lower energy:
•Visible light, Infrared radiation,
microwaves, radio waves