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Characteristics of radiation and radioactivity

Radiation and radioactivity have three main characteristics.

Characteristics of radiation and radioactivity

1)The greater the distance from a radioactive material, the weaker radiation becomes. 2)Radiation has the power to pass through materials (penetrating power), but it can be blocked. 3)Radioactivity decays over time.


Because the level of radiation is inversely proportional to the square of the distance, if you move twice the distance from a radioactive material, you will be exposed to 1/4 the level of radiation. It's like a flashlight: the further away you are, the weaker the light becomes.

2.Penetrating power

There are various types of radiation, including alpha rays, beta rays, and gamma rays. The penetrating power of the radiation depends on what type of radiation it is.
X-rays are another type of radiation. The lead apron that you wear when having an X-ray at the dentist's is actually to block radiation.

Types of radiation and their characteristics


Radioactivity becomes weaker as time passes, and the level of radiation decays over time. The time in which radioactivity decays to half its original level is called its half-life. Half-life differs depending on different radioactive materials.

How radioactivity decays
Radioactive materials and half-life