Radiation

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For other uses, see Radiation (disambiguation).

Radiation as used in physics, is energy in the form of waves or moving subatomic particles. Radiation can be ionizing or non-ionizing radiation, depending on its effect on atomic matter. The most common use of the word "radiation" refers to ionizing radiation. Ionizing radiation has enough energy to ionize atoms or molecules while non-ionizing radiation does not. Radioactive material is a physical material that emits ionizing radiation.

This shows three different types of radiation and their penetration levels

[edit] Types of Radiation

Electromagnetic radiation: (Energy in the form of electromagnetic waves or photons.)
- Non-ionizing
  - Radio waves
  - Microwave radiation, familiar to those who use microwave ovens.
  - Infrared radiation (IR), produced by heat
  - Visible light
  - Ultraviolet radiation (UV)
- Ionizing
  - X-rays, used in radiography for medical diagnosis
  - Gamma radiation, usually emitted by radioactive atoms

Particle radiation: (Energy in the form of moving subatomic particles.)
- Alpha radiation, composed of the nuclei of helium-4 atoms
- Beta radiation, consisting of energetic electrons or positrons
- Neutron radiation, consisting of neutrons

The effect of magnetic and electric fields on these particles/rays: Alpha particles being positively charged are deflected by both Magnetic and electric fields. Beta having a negative charge, are also deflected by both types of fields, but in the reverse direction to that of the alpha particles. Gamma rays have no charge, they are unaffected by these fields.