What are the Different Types of Radioactivity?

Radiation associated with radioactivity is an energetic form of radiation.

Radiation is defined as any movement of energy away from a central location. Radioactivity is an energetic form of radiation in which the nucleus of an element will, after a given time, break into two parts. There are three types of radioactivity.

Alpha Radiation

Alpha radiation is a type of radioactivity in which a helium nucleus is produced. For example, Uranium-238 decays into Thorium-234 and Helium-4. This helium nucleus is called an alpha particle. Though they are slow-moving particles, they are extremely dangerous inside the human body, but relatively harmless outside the body. The particle is positively charged and massive.

Beta Radiation

When a neutron changes into a proton, high-energy electrons are ejected from the nucleus. This is known as beta radiation. These negatively-charged particles move at 90 percent the speed of light and can penetrate human skin. Unlike alpha particles, beta particles are negatively charged and have little mass.

Gamma Radiation

Gamma radiation emits gamma particles, which are similar to photons -- light particles. They have very little mass and no charge, traveling at the speed of light. They are dangerous to humans because of their ability to penetrate virtually anything, including centimeters of lead.

References

• Launceston College: Natural Types of Radioactivity
• Brooklyn College: Radioactivity